Journal of

2015

JART

–English edition 2015–

The Japan Association of Radiological Technologists

Journal of JART—English edition 2015—

The Japan Association of Radiological Technologists

CONTENTS

2

Overview of the Japan Association of Radiological Technologists/general principles
Foreword

3

On Issue of Our English Language Journal
The Japan Association of Radiological Technologists Yasuo Nakazawa (President)

History and Activity

4
6

History of The Japan Association of Radiological Technologists (JART)
Efforts made by the Japan Association of Radiological Technologists
The Japan Association of Radiological Technologists Yasuo Nakazawa (President)

Commitments

12

Commitments made by the Fukushima Prefectural Association ofRadiological Technologists
Fukushima Prefectural Association of Radiological Technologists Kenji Suzuki (President)

Contribution

19

120 years since the discovery of the X-ray - The German Travelogue of X-rays26

the original work

Kunihiko Morozumi, Specialist, The Japan Association of Radiological Technologists

Arts and Sciences

Clinical usefulness of the serial ADC analysis in follow-up
evaluation after Gamma Knife surgery for metastatic brain tumors
Kohei Kawasaki, Osamu Nagano, Kyoko Aoyagi, Takahiro Kageyama

33

the original work

Measurement of anxiety regarding mammography for new radiological
technologists -Effectiveness of prescreening trainingAi Watanabe, Kyoichi Kato, Mitsuyoshi Yasuda, Mayumi Aso, Hisaya Sato, Azumi Isaka, Toshiyuki Takahashi, Yasuo Nakazawa

40

note

Diagnostic Reference Level (DRL) in the CT of Gunma
Hiroyuki Takei, Hidenori Otake, Yoshito Tsushima, Keigo Endo46

contribution

Development and Operation of an Image Interpretation Training System
Hironobu Tomita

52

the original work

Fundamental Study of easy decision method for Optimization of
Exposure Dose in Computed radiography.
Yasuo Mochizuki, Shinji Abe, Toshiaki Adachi, Masahiko Monma, Kojiro Yamaguchi

62

material

Actual Conditions of Intervention by Radiological Technologists in the Form ofQuerying Doubtful Points in Examining Request Slips from Physicians and Dentists
Yasuo Nakazawa, Masaru Nitta, Chikara Noda, Junya Nakashima, Hisaya Sato, Kyoichi Kato

71

contribution

Activities of medical radiologists at a central disaster base hospitalfollowing a major earthquake
Toshiki Tateishi

Note: The contents of this magazine are those that have been published in JART magazine.

Overview of the Japan Association ofRadiological Technologists
The Japan Association of Radiological Technologists, a public interest incorporated
association under the jurisdiction of the Ministry of Health, Labour and Welfare, wasestablished in 1947 with the purpose of contributing to the health of citizens throughraising the professional ethics of members, improving and furthering the study of medical
radiology and medical radiological technology, and enhancing public health.
In light of the startling progress being made in the fields of image diagnostics andradiation therapy where radiological technologists work, it is necessary to stay constantly
aware of the latest know-how and technology. JART collaborates with other certification
agencies to enhance the capacity of all radiological technologists in general throughproviding lifelong learning seminars, short courses, academic conferences and numerous
other learning opportunities. We believe that such activities constitute our obligation as
medical professionals to the general public.
As the only medical profession that has “radiological” in its name, we strive to limit
medical exposure, to raise the standing of our profession, and to realize a professionof specialist technologists that can be advertised. And we are committed to promoting
services with you all for the provision of safe and secure medical care.

general principles
We will render our services to those in need of health care.
We will act as individual members of a health care team.
We will perform our duties in our ﬁeld of specialty.
We will continue to study for the beneﬁt of mankind.
We will respect and practice the policy of informed consent.

2 ◆ Journal of JART English edition 2015

f o r e w o r d

On Issue of Our English Language Journal
Yasuo Nakazawa (President)

The Japan Association of Radiological Technologists, to commemorate the 120th anniversary ofthe discovery of X-ray, has issued a selection of articles considered to be particularly useful to radiological technologists throughout the world. These have been selected from the latest contributions
to “Journal of JART（J JART）” – the academic journal for radiological technologists in Japan.
The contents of “J JART” have three major features. First, they serve to advertise lifelong education
seminars to members in order to provide high quality medical technologies in collaboration with citizens and medical professionals. Second, they comprise articles on clinical radiological technology
research that is routinely conducted by members. And third, they comprise articles that are contributed by members and non-members based on medical science and technology. Approximately
30,000 copies of the journal are issued every month.
Now, to give the worldʼs radiological technologists some general idea of the work of their counterparts in Japan, I would like to briefly describe the history of the Japan Association of RadiologicalTechnologists. It was established in 1947 as part of the effort to enact a national examination for radiological technologists. Subsequently, it worked together with the government, National Diet, Japan
Medical Association, and the Allied Occupation authorities in forming consent on the national examination. Thanks to the tireless efforts soaked in the blood, sweat and tears of our founding members, the Act on Medical Radiographers was promulgated with the passing of Law No. 226 in June
1951. After that, responding to the needs of the age, the Act on Medical Radiographers was revisedin 1968; the Act on Radiological Technologists and the Act on Medical Radiographers underwent
partial revision in 1983, resulting in unification of the profession under the present Act on Radiological Technologists. The work of radiological technologists at this time comprised general X-ray examinations, X-ray TV examinations, angiographic examinations, X-ray CT examinations, RI examinations, and radiation therapy. Furthermore, the Act on Radiological Technologists was revised in
1993, making it possible for them to perform MRI examinations, ultrasonic examinations, andnon-mydriatic fundus photographic examinations. In 2010, the work of radiological technologists
was expanded to include assistance in the image diagnostic interpretation, and explanation andcounseling related to radiological examinations. And in April 2015, activities will be further expanded to include intravascular injection of contrast media using an automatic contrast media infusion
device, needle removal and stopping of bleeding, lower digestive tract examinations (anal insertionof catheter and infusion of contrast media), anal insertion of catheter and air suction during radiological treatment.
The Japan Association of Radiological Technologists is committed to expanding the work of radiological technologists based on scientific backing. We will continue to introduce the clinical, education, and research achievements of radiological technologists in “J JART” and strive to enhance its
contents. I hope that this English language journal will be a useful resource for radiological technologists throughout the world.
foreword ◆ 3

History

The Japan Association ofof Radiological Technologists (JART)

1947
1951

・ Establishment of JART (July 13)

1979

JART
・ Promulgation of the Act on Medical Radiog-raphers (June 11)1983

Association of Radiographers (June 13)

1985
・ First national examination for Medical Radi-

1962

・ Event to commemorate the 10

logical Technologists

1987

・ Promulgation of the Act to Partially Revise

the Act on Medical Radiographers (establishment of two professions) (May 23)
・ First national examination for radiological

1989

1991

diographers & Radiological Technologist (ISRRT) World Congress at Tokyo Palace Hotel,
attended by Her Imperial Highness Princess
Chichibunomiya

1975

1993

・ The Act to Partially Revise the Act on Radi-

ological Technologists, and Ministerial Ordinance to Partially Revise the Enforcement
Orders (April 28)

1994

・ Appointment of the President of JART as the

11th President of ISRRT

1995

・ Event to commemorate the 100th anniversaryof the discovery of X-ray, attended by Her
Imperial Highness Prince Akishinomiya

・ Event to commemorate the 80th anniversaryof the discovery of X-rays, attended by Her
Imperial Highness Princess Chichibunomiya

・ Opening of Suzuka University of Medical

Science・ Renaming as the JART・ Staging of the 4th International Society of Ra-

・ Completion of the New Education Center(Suzuka City)

technologists

1969

・ General assembly resolution for establish-

ment of the New Education Center and afour-year university

・ Event to commemorate the 15th anniversaryof founding and 10th anniversary of enactment of the Act on Medical Radiographers,
attended by Her Imperial Highness Princess
Chichibunomiya

1968

・ Staging of the 1st Japan Conference of Radio-thanniversaryof founding, attended by Her Imperial Highness Princess Chichibunomiya

・ Event to commemorate the 90th anniversaryof the discovery of X-rays, attended by Her
Imperial Highness Princess Chichibunomiya

ographers (May 30)

1956

・ Partial revision of the Act on Medical Radi-

ographers and the Act on Radiological Technologists (unification of the professions)・ Authorization for Establishment of the Japan1954

・ Completion of the Education Center for

1996

・ Start of the Medical Imaging and Radiologic

Systems Manager certification system

4 ◆ Journal of JART English edition 2015

• History of The Japan Association of Radiological Technologists (JART)

1998

・ Staging of the 11th ISRRT World Congress at

2010

Makuhari

1999

・ Start of the Radiation Safety Manager certifi-

concerning promotion of team medicine

2011

cation system

2000

2001

2004

・ Staging of an extraordinary general meeting

concerning transition to a public interest incorporated association

・ ” Presentation of the Medical Exposure
Guidelines (Reduction Targets)” for patients

2012
・ Start of the Radiological Technologists Liabil-・ Event to mark the 65th anniversary of found-ing and transition to a public interest incorporated association (June 2)

・ Enactment of X-Ray Week

・ Renaming as public interest incorporated as-sociation JART・ Relocation of offices to the World Trade・ Start of the Medical Imaging Information Ad-

ministrator certification system

2006

・ Launch of the Radiological Technologists

Liability Insurance System with participationby all members

2013

・ Revision of the Medical Exposure Guidelines

2014

・ Consignment of work to measure personal

exposure of residents
・ Establishment of the committee on Autopsy

・ Revision of the Act on Radiological Technol-

imaging (Ai)2009

・ Signing of the Comprehensive Mutual Coop-eration Agreement on Prevention of Radiation Exposure (September 21)

・ Staging of a joint academic conference be-

tween Japan, South Korea, and Taiwan

2008・ Registration of transition to a public interest

incorporated association (April 1)

Center Building in Tokyo

2005

・ Support activities following the Great East

Japan Earthquake

ity Insurance System

2003

・ Health Policy Bureau Directorʼs notification

ogists, Government Ordinance to Partially
Revise the Enforcement Orders, and Revisionof the Enforcement Regulations (June 25)

・ Revision to the national examination for ra-・ Launch of the radiation exposure advisor

diological technologists
・ Launch of the Team Medicine Promotion

Conference, with the President of JART as its
representative
・ Appointment of the President of JART as

certification system

2015

・ Event to commemorate the 120th anniversaryof the discovery of X-rays

chairperson of the Central Social Insurance
Medical Council specialist committee

History of JART ◆ 5

Activity
introduction

Efforts made by the Japan Association ofRadiological Technologists
The Japan Association of Radiological Technologists

Yasuo Nakazawa, President

1. Introduction
At approximately 14:46 on Friday, March 11, 2011, a massive earthquake of magnitude 9.0 occurred, whose hypocenter was about 130 km ESE off the Oshika Peninsula, Miyagi Prefecture. This
earthquake caused violent tremors over an extensive area from Hokkaido to Kanto. The great earthquake caused giant tsunamis along the Pacific coast of the Japanese archipelago; in particular, tsunamis which exceeded heights of 10 m caused serious damage to many places in the Tohoku area.
The giant earthquake and tsunamis hit the Fukushima Daiichi Nuclear Power Station of Tokyo Electric Power Company (TEPCO), resulting in a nuclear accident involving large amounts of radioactive
releases. The Japan Association of Radiological Technologists (JART) has dispatched radiological
technologists as radiation specialists to Fukushima Prefecture since March 16, 2011 up to now (as ofFebruary 20, 2012) in response to requests from the Ministry of Health, Labour and Welfare, theCabinet Office, and the Fukushima Prefectural Government. This report outlines the backgroundand efforts made by JART in this regard.

2. Background to the establishment of the Earthquake Disaster Countermeasure
Headquarters and request for dispatching radiation surveyors
On the night of Friday, March 11, the Government of Japan declared a state of nuclear emergency.
At TEPCO's Fukushima Daiichi Nuclear Power Station, enormous tsunamis inundated switchboards,
disabled power supply, washed out oil tanks for emergency diesel generators, and disabled the circulation of water to cool fuel rods which was the outset of the accident. On the afternoon of Saturday, March 12, a hydrogen explosion occurred at Unit 1 of TEPCO's Fukushima Daiichi Nuclear
Power Station. On the night of the same day, an evacuation directive was given out to residents
within 20-km radius of Fukushima Daiichi. Under these circumstances, JART established the Earthquake Disaster Countermeasure Headquarters headed by JART President at its main office on Saturday, March 12 and discussed the issue of securing and dispatching radiation surveyors (radiological
technologists) to cope with the radiological dispersal associated with the nuclear accident.
[Members of the Earthquake Disaster Countermeasure Headquarters]
Director-General: Yasuo Nakazawa (President)
Deputy Director-General: Kiyoshi Ogawa (Vice- President)
Deputy Director-General: Yasushi Ido (Vice- President)

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Efforts made by the Japan Association of Radiological Technologists

Head Official: Yoshiaki Kitamura (Director)
Clerical officers: headquarters staff
Local Response Headquarters Director: Kenji Suzuki (Director, President of Fukushima Prefectural
Association of Radiological Technologists)[Roles of the Earthquake Disaster Countermeasure Headquarters](1) Coordination with the Local Response Headquarters
List of dispatched personnel, transportation means, and health checkup of dispatched personnel(2) Coordination with surveyor applicants
Designation of leaders, forwarding of commissioning letters, and confirmation of contact information(3) Surveyor activity report
Report to 47 Prefectural Governments(4) Report on the procurement and management of GM counters, pocket dosimeters, etc.
(5) Survey report on damage in each prefecture of the Tohoku region(6) Coordination with administrative agencies(7) Consultation on radiation exposure(8) Handling the public and mass media
At about 3:40 p.m. on Saturday, March 12, there was a request from TV Tokyo to make an impromptu appearance on TV. The Earthquake Disaster Countermeasure Headquarters discussed thematter at a meeting and decided to dispatch JART members Mr. Kunihiko Morozumi (Chairman of
the Medical Exposure Safety Control Committee) and Mr. Hiroshi Watanabe (Acting Officer for Public Relations). We also asked for cooperation from all directors, 47 prefectural association president,
officers, and radiation safety managers by email sent at 8:15 a.m. on Sunday, March 13.

[Request for cooperation sent to members throughout Japan]
Good morning, everybody.
(1) We would like to ask all the directors, 47 prefectural association president, and officers to collect information in each prefecture and promulgate correct knowledge on radiation according
to our established policy when asked to offer consultation on radiation.
(2) According to media reports, about 160 residents have been exposed to radiation. Radiation
surveys on residents may be conducted in the future. If there is a request to mobilize radiation
safety managers and other personnel, we will cooperate as much as possible. If you havebeen mobilized on a prefectural basis, please report to the president of your prefectural association either before or after the mobilization. JART will communicate with each prefectural
association president and pay for transportation, lodging, and measuring apparatus rentals asnecessary.
(3) We ask the radiation safety managers throughout Japan to pay attention to media reports andcooperate in conducting emergency response to the extent possible for each person.
(4) As regards media relations, please be aware that Mr. Morozumi, Chairman of the Medical Exposure Safety Control Committee, will again appear on TV Tokyo today.
Activity ◆ 7

Activity introduction(5) Mr. Okada, Radiation safety managers Committee Chairman, and Mr. Ido, Vice President, arenow preparing a nation-wide list of radiation safety managers who can be mobilized on a voluntary basis. I hope the association president throughout Japan will cooperate with requests
from Mr. Okada.
(6) Please contact myself, Nakazawa (phone: 080-5916-8877) if you have any questions.
8:15 on Sunday, March 13, 2011
Yasuo Nakazawa, President of the Japan Association of Radiological Technologists

At around 10 a.m. on Sunday, March 13, the Atomic Energy Commission of the Cabinet Office and
the Guidance of Medical Service Division of the Ministry of Health, Labour and Welfare asked us
about the number of radiation surveyors we can dispatch and the number of GM counters we canlend to serve residents evacuated to shelters from the vicinity of TEPCO's Fukushima Daiichi Nuclear Power Station. Responding to this request, we held a second meeting of the Earthquake Disaster
Countermeasure Headquarters to urgently solicit contributions from radiation surveyors and procure
GM counters. Being also requested for cooperation by the Fukushima Disaster Countermeasure
Headquarters (Coordination Headquarters for Emergency Exposure Medical Treatment), we consulted Mr. Suzuki, President of the Fukushima Prefectural Association of Radiological Technologists, anddiscussed plans to dispatch radiation surveyors to Fukushima Prefecture for a long time period. Responding to our solicitation, 12 radiological technologists from around the country gathered at the
JART main office on Wednesday, March 16. After holding a kickoff ceremony, they headed for Fukushima Prefecture on a chartered bus registered as an emergency vehicle. The kickoff ceremony wasreported by NHK TV on the same day. On Friday, March 18, JART received an office memo entitled"Request for cooperation with health centers, etc." from the Local Healthcare Office, General Affairs
Division, Health Service Bureau, the Ministry of Health, Labour and Welfare. The memo mainly requested dispatching radiological technologists to prefectures or cities where health centers were located as well as lending GM counters. In response, JART asked the 47 prefectural associations of radiological technologists for cooperation. Based on an office memo from the Ministry of Health, Labour and Welfare, the Tokyo Metropolitan Government asked JART and Tokyo Association of Radiological Technologists for cooperation in radiation surveys on a voluntary basis. In response, theTokyo Association of Radiological Technologists conducted radiation surveys from Thursday, March
24 to Tuesday, May 17 on evacuees who sheltered at Tokyo Big Sight and Ajinomoto Stadium. On
Friday, April 8, there was a request from the Fukushima Prefectural Police Headquarters through the
Ministry of Health, Labour and Welfare asking for radiation surveys on bodies before autopsy. We
consulted Mr. Suzuki, who was in charge of local emergency response as President of the Fukushima Prefectural Association of Radiological Technologists, and conducted radiation surveys on bodies
before autopsy during the period from Monday, April 11 to Wednesday, August 10. On Thursday,
July 28, there was a request from the Ministry of Health, Labour and Welfare for dispatch of radiation control specialists to TEPCO's Fukushima Nuclear Power Station. JART has dispatched radiological technologists since Wednesday, August 31 up to now (as of Monday, February 20, 2012). On
Sunday, February 5, 2012, there was a request from the Environmental Health Department of the
Ministry of the Environment for a model project to support risk communication in Fukushima, andwe operated an Internet consultation center on radiation exposure from Monday, February 20 toSaturday, March 24.

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Efforts made by the Japan Association of Radiological Technologists

3. JART's policy on emergency exposure
In 1999, we started to qualify radiation safety managers in a new qualification system of radiological technologists. This system has the following objective:(1) Nurture specialists to promote knowledge among the public on the safe use of radiation,(2) Nurture specialists who lead and promote radiation hazards prevention and management
techniques,(3) Nurture specialists who conduct research projects for reducing medical exposure, and(4) Nurture specialists who lead the development of emergency exposure preparedness.
Prior to the new qualification system, we have been providing professional training on clinicalpractices and conducting corresponding qualification tests by assuming medical care as the main
field of activity. Meanwhile, one of the above-mentioned four objectives of the radiation safety managers qualification system is to nurture specialists who lead the development of emergency exposure preparedness. The lecture themes include "nuclear power related facilities" and "flow of air."Radioactive steam was released to the atmosphere due to the nuclear accident at TEPCO's Fukushima Daiichi Nuclear Power Station and residential areas were radioactively contaminated; thus, radiation safety managers, as radiation control specialists, are in charge of instructing radiation surveys toease the anxiety of residents in such areas. As an organization to nurture radiation safety managers,
we have been dispatching radiation surveyors as a must-do project of JART. Currently, about 2,755
radiological technologists are qualified and working nationwide as radiation safety managers.

4. Requests for supporting the health care of disaster victims
Since we started to dispatch radiological technologists to the Fukushima Disaster Countermeasure
Headquarters on Wednesday, March 16, 2011, various problems have arisen. We summarized suchproblems, identified items necessary for delivering relief for disaster victims in Fukushima Prefecture
and other areas, and submitted a petition to the Liaison Council for the Health Support of Disaster
Victims. The specific items of the petition are as follows:(1) Development of an efficient system of radiation survey on disaster victims
In the current system of radiation survey on disaster victims, dispatch may be requested separately from different organizations such as the Ministry of Education, Culture, Sports, Scienceand Technology, the Ministry of Health, Labour and Welfare, and the Federation of ElectricPower Companies of Japan, and screening is conducted at permanent facilities in Fukushima
Prefecture. The number of examination personnel including radiological technologists differsfrom day to day. For efficient deployment of personnel, we would like to ask the responsible
persons to review and develop a chain of command and other systems. As many people haveasked about radiation effects at permanent facilities and at least one radiological technologist
must be stationed at each facility, we would like to ask the responsible persons to consolidate
the chain of command and respond to medical institutions that are under the jurisdiction of
the Ministry of Health, Labour and Welfare and the Ministry of Education, Culture, Sports, Science and Technology.

Activity ◆ 9Activity introduction(2) Response to radiation exposure and health study
The valuable data of atomic bomb survivors in Japan are being used for determining international criteria on the health effect of radiation; 100 mSv in one incident of exposure has beenused as the lower limit of detecting any effects.
Although the radiation exposure caused by the Fukushima nuclear accident was at low doselevels close to the detection limit, it is necessary to develop a system to conduct health studies
on disaster victims and follow-up studies. A system for conducting studies in consideration of
10 to 20 years from now should be developed urgently.
(3) Response to harmful rumors associated with radiation exposure
In response to the fact that there are harmful rumors associated with radiation exposure, therelevant groups and associations should present a unified view on the effect of radiation exposure and explain the radiation effects on human health.
Harmful rumors are severely affecting not only the primary industries but also the export ofindustrial products. Some local governments even responded by expressing an attitude of
avoidance of people living in the areas affected by the nuclear accident. While the responseto the accident becomes prolonged, we urge people to address human rights issues as well.
(4) Development of radiation-related legislation and emergency response manual
The introduction of tentative regulation limits and emergency exposure limits after the occurrence of the accident have caused public distrust and a great disturbance in daily life. The safe
operation and emergency response of nuclear facilities should be discussed in combination.
(5) Cross-ministerial development of regulations
At sites where people handle radiation, background radiation doses continue to be higher
than doses in controlled areas, and consistency with the current laws cannot be achieved withrespect to control criteria and other aspects. We earnestly urge administrative authorities to respond appropriately.
The petition, with the above five items, was discussed by the Liaison Council for the Health Support of Disaster Victims and summarized into three items as an official request from the Council; therequest was submitted from Mr. Haranaka, Representative of the Council, to Mr. Tatsuo Hirano, Minister of State for Disaster Management of the Cabinet Office in charge of recovery from the Great
East Japan Earthquake.

5. Response to mass media
At around 3 p.m. on Saturday, March 12, 2011, TV Tokyo asked JART to make an appearance on
TV. We were requested to comment, as radiation specialists, on how we should address the anxietyof local residents about radiation exposure caused by the nuclear accident at TEPCO's Fukushima
Daiichi Nuclear Power Station. We contacted JART members Mr. Kunihiko Morozumi (Chairman of
the Medical Exposure Safety Control Committee) and Mr. Hiroshi Watanabe (Acting Officer for Public Relations) and dispatched them to TV Tokyo. They subsequently made appearance more than 30
times on Fuji Television Network, TV Asahi, FM J-WAVE, Fukushima Broadcasting, and other broadcast stations to provide explanations as radiation specialists.

10 ◆ Journal of JART English edition 2015

Efforts made by the Japan Association of Radiological Technologists

6. Summary
As requested from the Ministry of Health, Labour and Welfare, the Atomic Energy Commission of
the Cabinet Office, and the Fukushima Disaster Countermeasure Headquarters, JART called for voluntary cooperation from the 47 prefectural associations of radiological technologists. Many people
volunteered from across the nation, and we managed to dispatch radiation surveyors to Fukushima
Prefecture. The Fukushima Disaster Countermeasure Headquarters has acknowledged that our efforts have greatly helped reduce the anxiety of residents who have evacuated to shelters. Fukushima
Prefectural Governor Yuhei Sato also acknowledged our activities. Responding to a request from the
Ministry of Health, Labour and Welfare to dispatch radiation control specialists, JART has dispatchedradiological technologists to TEPCO's Fukushima Nuclear Power Station. JART believes its mission
to support the reconstruction efforts of people in the disaster-affected areas. Representing JART, I
would like to express our sincere thanks to the volunteers who have responded to our solicitation,
the family members who supported the volunteers, the officers of the 47 prefectural associations ofradiological technologists who have been cooperative, and the facility directors who have approved
the dispatch of their personnel.
Finally, I would like to extend my heartfelt sympathies to those who have been affected by theGreat East Japan Earthquake and would like to pray for the souls of the deceased.

Activity ◆ 11

Activity
introduction

Commitments made by the Fukushima
Prefectural Association of RadiologicalTechnologists
Fukushima Prefectural Association of Radiological Technologists

Kenji Suzuki, President

Introduction
The gigantic earthquake of magnitude 9 that occurred off the Sanriku coast in the Tohoku region
on Friday, March 11, 2011 was the severest earthquake on record in Japan. In addition to the collapse of buildings, the tsunamis associated with the earthquake resulted in more than 20,000 people
killed or missing. The next day on March 12, the tsunami disabled the cooling capability of Unit 1 of
Fukushima Daiichi Nuclear Power Station, and the reactor building of the unit experienced a hydrogen explosion. As a result, radioactive iodine (I-121) and cesium (Cs-137) were released, and an
evacuation directive was given out to residents within a 20-km radius of the power station. Shelters
were set up throughout Fukushima Prefecture, and evacuees were subjected to emergency exposure
screening.

Background to the dispatch of screening personnel
Eight to nine Fukushima Association members participate in the Fukushima Prefecture Nuclear
Emergency Drills held annually by the Fukushima Prefectural Government to perform training on
emergency exposure medical treatment according to the Fukushima Prefecture Emergency Exposure
Medical Activity Manual. According to this manual, radiological technologists play a role in preparing the opening of first-aid stations, conducting body surface contamination monitoring with survey
meters, and deciding the necessity of decontamination; all the work is conducted under the direction of the Nuclear Emergency Response Center of Fukushima Prefecture (off-site center in Okuma-machi). As the off-site center did not function during the Fukushima nuclear accident, things did
not proceed as stipulated in the manual, and this caused confusion (Fig. 1). After the onset of the
Fukushima nuclear accident, all communication means were lost due to the disaster. Therefore, theFukushima Association received no request for dispatch, and persons in charge of nuclear emergency drills at the Fukushima Prefectural Government could not be reached by either home telephone
or mobile phone. On Sunday, March 13, I decided to go to the Fukushima Medical University Hospital.
(It was fortunate that telephones were usable at the hospital.)
I confirmed that the Ministry of Education, Culture, Sports, Science and Technology had requested

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Commitments made by the Fukushima Prefectural Association of Radiological Technologists

the Fukushima Medical University Hospital to dispatch emergency exposure screening personnel.
After asking Mr. Kazumori Matsuo, Emergency Response Measures Examiner of the Nuclear Safety
Commission, to let the Fukushima Prefectural Government request to the Fukushima Prefectural Association for dispatch of personnel, I went home and sent an email to the director of the Fukushima
Association to request for dispatch. Immediately after this I went to the Fukushima Disaster Countermeasure Headquarters (Fukushima City) and received an oral request for dispatch from the person in charge for the Fukushima Prefecture. As a result, the dispatch of personnel for screening
started on Monday, March 14. While I accepted the request for dispatch, I had to rely on telephone
as an urgent means of communication. As I could not use my home telephone or mobile phone, I
waited in line at a convenience store for a public telephone. As I made a phone call to one person
to talk about the request for dispatch, I let the next person in line use the phone. I repeated thisprocess several times to contact association members.

Development of screening system
On March 14, I asked Vice- President Yasuo Saito to organize the southern prefectural branch, anddispatched screening personnel to Koriyama City Gymnasium and Fukushima Prefecture Gender
Equality Center (Nihonmatsu City). Meanwhile, Mr. Ikuo Watanabe, Deputy Director of the Aizu
branch, informed us that there was a shortage of GM survey meters at the Fukushima Prefectural
Aizu General Hospital, where he was conducting screening. As we possessed GM survey meterstransferred from former President Toshihiko Katakura and slated for disposal, we promptly transported two of the GM survey meters to the Aizu General Hospital. The next day on Tuesday, March
15, the Fukushima Medical University Hospital and the Fukushima Preservative Service Associationof Health also requested for the dispatch of personnel for screening, and the northern prefecturalbranch became ready to conduct screening as well.
As regards the screening system, the Division of Community Health Care of the Department of
Health and Welfare of Fukushima Prefecture issued a detailed document describing specific actions
to be taken; screening would be conducted according to this document (Fig. 2). In the initial stageof screening, many residents flocked to shelters and screening facilities and they ended up waitingfor 4 to 6 hours to be examined. The screening conducted on March 15 at the University of Aizu
lasted until 3 a.m., during which time personnel of the Aizu branch continuously conducted measurement. Meanwhile, additional shelters were set up at different locations and we began to circulate
the shelters for screening. It became usual for one team to conduct screening at three shelters, andresulted in excess burden placed on the association members (see Table 1 and Fig. 3).
The Coordination Headquarters for Emergency Exposure Medical Treatment was set up to allow
the association members to report each day's activities and plan the next day's screening and medical activities. This resulted in reviewing any problems within the day and feeding the results back to
the next day's activities. I also participated in the meetings of the Coordination Headquarters (Fig. 4).

Screening work
The screening on Wednesday, March 16 dealt with residents and nuclear workers who were radioactively contaminated; at the facilities where the Fukushima Association dispatched personnel, 137
Commitments ◆ 13

Activity introduction

persons were found to have radiation levels of 13,000 to 100,000 cpm and 4 persons had radiationlevels of 100,000 cpm or more.
The latter 4 persons were TEPCO workers from Fukushima Daiichi Nuclear Power Station. In one
person, contamination was found in the hair and the lower body, and after decontamination, radiation levels were reduced to 20,000 cpm in the hair and 10,000 cpm in the lower body. Table 2
shows the number of personnel dispatched by the Fukushima Association and the number of people screened. During the period between the onset of the Fukushima Daiichi nuclear accident andWednesday, May 25, the number of people screened at all the permanent screening facilities andshelters in Fukushima Prefecture reached 192,933; among them, 894 had radiation levels of from13,000 to 100,000 cpm, and 102 had radiation levels of 100,000 cpm or higher. The examiners were
initially wearing a Tyvek suit, cap, mask, and shoe covers during the screening work. From Sunday,
March 20 onward, given that the number of people having radiation counts of 100,000 cpm or more
had decreased, they stopped wearing Tyvek suits, which may look scary to residents. As the number of residents screened decreased, more people began to bring cars, vegetables, clothes, pets, soil,
and industrial goods for screening. As the Coordination Headquarters for Emergency Exposure Medical Treatment could not handle every request, they introduced the following criteria for conducting
screening.
(1) Cars left within 20-km radius are screened because their radiation counts are high.
(2) Pets accompanying the residents are screened.
(3) Vegetables cannot be evaluated properly because GM survey meters can measure only surfaces.
(4) Industrial goods are screened at the Fukushima Technology Centre.
Although the number of people screened has decreased, if evacuees are allowed a temporary visit
to their homes within 20-km radius, we will need to screen these residents once again so that the
number of people examined will increase. We must therefore discuss the screening system of the
future.

Concluding remarks
The commitments of the Fukushima Prefectural Association of Radiological Technologists toward
the future should focus on easing the anxiety of residents. Based on our specialist knowledge, wewould like to actively address radiation-related questions raised by residents. Even within Fukushima Prefecture, people are sometimes not accepted for examination at a medical institution or not allowed to access shelters if they have not been screened. To address such and many other problems
related to radiation, I keenly feel the need for enlightening residents on radiation.
There are harmful rumors that Fukushima Prefecture is entirely contaminated with radioactive material; as a result, some people refrain from accessing areas even where contamination is negligible
and avoid purchasing products from Fukushima Prefecture. Transmission of correct information
through the mass media is badly needed.
(From the interim report of June 11, 2011 prepared by the late Mr. Kenji Suzuki)

14 ◆ Journal of JART English edition 2015

Commitments made by the Fukushima Prefectural Association of Radiological Technologists

Off-site center(Nuclear Emergency Response Centerof Fukushima Prefecture)
National
Government
Nuclear
Emergency
Response
Headquarters

Local
government
Local nuclear
emergency
response
headquarters

Joint Council for
Nuclear Emergency
Response(medical section)

Local emergency
response headquarters(medical section)
AdviceEmergency exposure
medical treatment teamTechnical
adviceNuclear Safety Commission
Nuclear power operators

Instruction,
advice,and support

Dispatch

Radiation emergency hospitals, etc.

Primary radiation emergency hospitals, etc.
Coordination
Secondary radiation emergency hospitals, etc.
Coordination
Secondary radiation emergency hospitals
Coordination
Tertiary radiation emergency hospitals

Fig. 1 Framework of emergency exposure medical treatment system(Exc Fukushima Prefecture Emergency Exposure Medical Activity Manual)Commitments ◆ 15

Activity introduction

Description of emergency exposure screening system
March 14, 2011
Division of Community Health Care, Department of Health and Welfare
The screening system on and after March 15 shall be as follows.
1. Basic philosophy
Ensuring the safety and security of residents
2. Speciﬁc actions(1) Actions at each shelter
Screening and decontamination are conducted by a team consisting of healthcenter personnel and supporters.
(2) Others (severely exposed patients)
Once the Emergency Response Headquarters receives information, the client willbe transported to Fukushima Medical University or the National Institute of Radiological Sciences, depending on the state of exposure.
3. Change in screening levels(1) Description of change
The current screening level of 13,000 cpm for whole-body decontamination will
be changed to 100,000 cpm.
If radiation levels between 13,000 cpm and 100,000 cpm are detected, partial wiping for decontamination will be conducted.
The change shall become effective as of March 14, 2011.
(2) Reason for change
The change was decided on March 13, 2011 based on the opinions of specialists
on radiation exposure medical treatment dispatched by the Ministry of Education,
Culture, Sports, Science and Technology to Fukushima Prefecture and researchers
from the National Institute of Radiological Sciences, as well as the treatment adopted at Fukushima Medical University.
(3) Explanation to residents
The above actions will ensure that there will be no health effect on the residents.
4. Treatment of wastewater in decontamination
On the basis of the opinions of the above-mentioned specialists, the wastewater
generated will be treated as general drainage because its expected radiation levels
will not affect the environment.

Fig. 2 Description of emergency exposure screening system

16 ◆ Journal of JART English edition 2015

Commitments made by the Fukushima Prefectural Association of Radiological Technologists

Fig. 3 Screening in practiceFig. 4 Fukushima Prefectural Coordination
Headquarters for Emergency Exposure
Medical Treatment

Table 1 Permanent facilities and shelters where the Fukushima Prefectural Associationof Radiological Technologists conducted screening (35 locations)

Aizu General Hospital

Minami-Aizu Hospital

Fukushima Gender
Equality Centre

Koriyama City
Gymnasium

University of Aizu

Fukushima Technical HighSchoolFukushima-Kita HighSchoolDate City Gymnasium

Hashirazawa Community
Hall

Fukushima High School

Yanagawa High School

Date City Fureai Center

Aizu Dome

Fukushima Terrsa

Paruse Iizaka

Fukushima-shi Daisan
Junior High School

Kawamata-machi Iizaka
Elementary School

Kawamata-machi
Tsuruzawa Community
Hall

Kawamata-machi HealthCenterBig Palette Fukushima

Fukushima Meisei HighSchoolFukushima-shi Nankodai
Elementary School

Hobara Daini Gymnasium

Yoshiida Learning Center

Shinryo Learning Center

Mochizuri Learning
CenterFukushima Commercial
High School

Fukushima Training
Center For Local Officers

Horai Elementary School

Horai Junior High School

Yamatsuri Local
Community Development
CenterHanawa Community Hall

Kawamata High School

Shinobu Learning Center

Ichiban-kan

Commitments ◆ 17

Activity introduction

Table 2 Number of personnel dispatched and the number of people screened by
the Fukushima Prefectural Association of Radiological Technologists

Date

No. of locations

No. of personnel
dispatched

No. of people
screened

13,000 or more, lessthan 100,000 cpm(No. of people)

100,000 cpm or more
(No. of people)

March 13

1

4

27

0

0

March 14

4

14

1,517

0

0

March 15

6

20

4,711

41

0

March 16

5

17

3,535

137

4

March 17

9

22

3,314

22

0

March 18

7

27

2,620

40

1

March 19

9

28

2,196

25

1

March 20

5

22

1,519

7

0

March 21

4

22

1,124

2

0

March 22

4

18

1,584

33

0

March 23

3

9

718

3

0

March 24

3

7

765

2

0

March 25

3

8

767

1

0

March 26

2

4

510

2

0

March 27

2

5

512

0

0

March 28

2

3

425

0

0

March 29

2

3

404

4

0

March 30

2

3

431

0

0

March 31

2

3

465

3

0

April 1

1

2

131

0

0

April 2

1

2

108

0

0

April 3

1

2

130

0

0

April 4

1

2

84

0

0

April 5

1

2

77

0

0

April 6

1

2

54

0

0

April 7

1

2

74

0

0

April 8

1

2

63

0

0

April 9

1

2

82

0

0

April 10

1

2

148

0

0

April 11

1

2

70

0

0

April 12

1

2

101

0

0

April 13

1

2

84

0

0

April 14

1

2

44

0

0

April 15

1

2

78

0

0

April 16

1

2

122

0

0

April 17

1

2

110

0

0

Total

92

273

28,704322

618 ◆ Journal of JART English edition 2015

contribution
c o n t r i b u t i o n

120 years since the discovery of the X-ray- The German Travelogue of X-rays
Kunihiko Morozumi
Specialist
The Japan Association of Radiological Technologists

radiation dose in time units, I indicate to you
the in-flight dosage rate (Diagram 1). Whenthe altitude surpassed 10,000m, the value thatwas 0.05 μ Sv/h on the ground reached 1.5 μ
Sv/h.
Frankfurt is situated in the topographicalcenter of Germany and is the railroad heartland (Diagram 2). Considering my subsequent
travels, I stayed at a hotel near Frankfurt(Main) Hauptbahnhof (central station) andmade that my starting point. Being a giant metropolis, Frankfurt is also convenient for shopping, and there are also many sightseeing
spots. Buying the Frankfurt Map (€0.50) at the
Tourist Information makes things handy.

This year is the 120th anniversary since thediscovery of the X-ray by Wilhelm Conrad
Röntgen (1845 - 1923) in November 8th, 1895.
In August 2014, I visited Germany and visitedplaces that had connection to Röntgen and
the X-ray. I then wrote a German travelogue
different from the usual ʻ Romantic Road ʼtheme. It is my hope that this travelogue will
be helpful to people planning a trip to Germany in the times ahead. Further, the namesof places, transportation situation, and theEuro (€) within this document are all as it wasin August 2014.
A trip by plane to Germany from Japantakes 11 hr and 30 min. This time, since I wasplanning to visit Röntgenʼs grave first, I wentfrom Haneda airport to Frankfurt.
Since I took the D-shuttle Dosimeter (Chiyoda Technol Corporation) that can determine

Average dosage rate {μSv/h}Introduction

Giessen

Shift in dosage rate in August 2014

The railroad is developed in Germany like it
is in Japan. That dogs and bicycles confidently
occupy spaces on trains dedicated to them is[Day]

Shift in dosage rate on August 7th, 2014
Average dosage rate {μSv/h}

Average dosage rate {μSv/h}

Shift in dosage rate in August 2014

[Day]

[Time]

Diagram 1: Measured results of the personal exposure dosimeter (D-shuttle)
Average dosage rate {μSv/h}

Shift in dosage
rate onrate
Augustis
7th,shown2014
The reason why a highdosageon August 7th and August 15th in the top diagram is due to the altitude of
11,000 m during the flight. The peak on August 7th at 10 am in the lower diagram is due to passing through the baggage
inspection section. The average dosage rate during the flight following boarding LH717 at 2:15 pm was at maximum 1.5μSv/h.

Contribution ◆ 19
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an enviable scene. If you buy a German Rail
Pass and a reserved seat on a train along withyour plane ticket from your travel agent before leaving Japan, it will be handy when verifying the train number and the track that thetrain will be departing from is concerned. It
depends on the season, but it was 30,000 yen
including service fees for 2nd class seats for 3
days. Further, 3 days means any 3 days withina month and continuous use is unnecessary.
All you need to do is get a confirmation forthe day you ride the train.
The timetable is not by train line, such as
the Tokaido Line or the Joetsu Line; all thetrains departing from the station are arranged
according to the time of departure. Therefore,
it would be a good idea to check the numberof the train you will be taking the next day
along with the track number.
Since there is no ticket gate at German train
stations, you just get on the train. However,the conductor will come to inspect your ticketin the train. This is when you show your German Rail Pass and get the date marked onyour ticket.
Giessen is approximately 40 minutes fromFrankfurt and is where Röntgen spent his time
as a professor of physics at the University of
Giessen from 1879 to 1888. The school build-ing where he taught still remains (Photo 1).
After getting of at Giessen station, and youplan to go by taxi, tell the taxi driver, Alter
Friedhof (old cemetery). My German waspoor and so the taxi took a detour via Neuer
Friedhof (new cemetery). On the gate is abulletin board by the University of Giessen
who manages the gravestones. There is an information map (pamphlet) for this cemeterybecause there are many other famous peopleburied here. Thus, here and there within thecemetery, are direction boards leading to
Röntgenʼs grave. Follow these direction boards
for about 200 m, and you will arrive at Röntgenʼs grave.
The grave was immaculately clean and decorated with beautiful flowers. Both Wilhelm
Conrad Röntgen and his wife Berta as well as
his parents are buried here (Photo 2). If you
look at the gravestone, you will see that Bertha died at the age of 89 on October 31st,1919. Then, 3 years following her death, Wilhelm Conrad died on February 10th, 1923, justa little over a month before his 78th birthday.
Although Wilhelm Conrad Röntgen is spelledwith a C in all literatures, the gravestone is inscribed with his name spelled as KONRAD.
On the way to Giessen station from Alter
Friedhof (old cemetery), when you turn the

Photo 1: Justus Liebig University Giessen(University of Giessen)

Photo 2: Professor Röntgenʼs gravestone
Röntgen ʼ s gravestone was very tranquil at the Alter
Friedhof (old cemetery)

The Justus Liebig University Giessen (University of
Giessen) was where Röntgen spent his years from 1879 –1888 as a professor of physics.

20 ◆ Journal of JART English edition 2015

120 years since the discovery of the X-ray - The German Travelogue of X-rays

Photo 4: Deutsches Röntgen-Museum

Photo 3: Röntgenʼs monument
A memorable monument shaped like a new ray of lightgoing through a billet in an angle. There is a relief of
Röntgen on the pedestal.

corner at Ludwigs Patz and arrive at Berliner
Platzt, you will see a monument shaped like a
ray of light going through a billet in an angle( Photo 3) on the left of the park from the
Stadttheater theater. The following inscription
can be found on the pedestal with Röntgenʼsrelief: “Wilhelm Conrad Röntgen (1845 - 1923)
was a full professor of physics at the University of Giessen from 1879 - 1888.”

Remscheid-Lennep
Lennep, where Röntgen was born, was an
old town along the commercial route heading
toward the Baltic Sea. It was annexed by thecity of Remscheid in 1929 and hence is now
Remscheid-Lennep.
You get off at the branch line of Wuppertal
via Koln from Frankfurt. Then, from there,
you head toward Remscheid-Lennep on thebus. You get off at the front of Lennepʼs old
station building, but due to the fall in users of
trains, the station building was surrounded byan iron fence and looked forlorn and miserable.

Photo 5: Exhibits in the museum (Röntgen lost inthought)

Turn your back on the station building andwalk along the ring-shaped street. On the left
side you will see a sign saying, Deutsches
Röntgen-Museum. Continue to walk while trying to remember the location of the street signfor your return treck. The Deutsches Röntgen-Museum (Photo 4) is closed on Mondays,
so if you want to go you should verify thedays and times the museum is open in advance.
When you walk in, on the right is the oldHaus 1. Here, you will find things related to
Röntgenʼs life, furniture that he used, etc. on
exhibit. In Haus 2 and Haus 3, you will findthings related to X-rays such as the basics tothe applied, as well as the earliest up to thelatest X-rays orderly exhibited (Photo 5).
The history of the development of X-ray
Contribution ◆ 21

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Photo 6: Exhibits in the Röntgen-Museum
Devices that were active during the First World War

Photo 8: Physics Laboratory, University of
Würzburg

I wasnʻt able to see it this time, but I would
like to make it my reason for visiting the placeagain.

[This is the house where Wilhelm Conrad
Röntgen, the person who discovered the‘ray’ named after him was born on March
27 th 1845. In 1896, he was conferred thetitle of honorary townsperson from thetown that was his hometown.]
Photo 7: Röntgenʼs birthplace
It was being worked on (under construction) in thesummer of 2014.

equipment such as the various X-ray tubes,
the vacuum pumps, induction coils, generators, and accessories are exhibited (Photo 6).
If you walk out of the museum and turnleft, and then turn right at the fork in the roadup ahead and keep walking for about 100 m,
you will find Röntgenʼs birthplace (Photo 7).
Since the house was hard to differentiate fromthe other houses, I asked a local person
which one it was and showing a photo I
brought from Japan. It was the house underconstruction. I wanted to verify the nameplateof Röntgenʼs birthplace, but I was unable to as
it was hidden by construction work fence.
However, something like the following is apparently written in German.１）

22 ◆ Journal of JART English edition 2015

Würzburg
Würzburg is 70 min from Frankfurt and is abeautiful sightseeing spot on the northern
starting point of the ʻRomantic Road.ʼ Röntgenmarried Bertha while working at the University of Würzburg as an assistant from 1870 to1872. Subsequently, while working as a professor of physics (1888 - 1900), he discovered
the X-ray.
If you turn right on Röntgen Ring from
Würzburg Hauptbahnhof (Hbf or Würzburg
Central Station), there is a monument to thediscovery of the X-ray between the Universityof Würzburg buildings. If you proceed further,
there is a light green building (Photo 8) whichis the University of Würzburgʼs physics laboratory, and in the left corner of the room on the
2nd floor, the X-ray was discovered during re-120 years since the discovery of the X-ray - The German Travelogue of X-rays

search on the cathode ray. On the wall surface is written, “In this room, Wilhelm Conrad
Röntgen discovered the ray named after him
in 1895” (Photo 9). On the 1st and 2nd floors
are the physics laboratory, the experimentallaboratory, and the lecture room. The 3rd
floor is the division where the Röntgens resided and was also a place where Röntgen wasable to lead the most enjoyable fulfilling daysof his life.2）
After passing that and moving on for another 10 m, there is the entrance to the Röntgen
Memorial. When you open the heavy door on
the 2nd floor, you will enter a hall. Proceeding

down the left corridor will lead you to theroom where Röntgen actually discovered the
X-ray. You can see the room through a transparent plastic door (Photo 10).
Here, the device used by Röntgen to discover the X-ray is exactly the same as it was atthat time. However, the Ruhmkorff coil is a
replica and the real thing is exhibited at Munichʼs Deutsches Museum. Devices and equipment used at the laboratory during thosetimes are exhibited in the adjoining room andthese historical exhibits are worth seeing.
You will be able to fully enjoy the old cityscape of Germany if you tour the famous residences, the Marienberg Fortress, and more after visiting the physics laboratory.

MunichPhoto 9: The name plaque on the wall of the
Physics Laboratory, University of
Würzburg

In Munich, I looked for the building where
Röntgen spent his last days. German streets
are indicated with historical figures, and there,at 11 Maria Theresia street, was a brilliant
modern 2-story residential building built ofbright brown bricks (Photo 11).
The following was written on the wall
plaque ( Photo 12 ) displayed at the house
where Röntgen passed away.1）“Wilhelm Conrad Röntgen, the full professorof Experimental Physics at the University of
Munich (tenure years 1900 - 1923) and also

Photo 10: The laboratory where Röntgen
discovered the X-ray

Photo 11: The building where Professor Röntgen
passed away
Contribution ◆ 23

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Photo 12: The plaque describing Professor
Röntgenʼs passing

all the exhibits. In one corner of the physics
exhibit room (1st floor: 2nd floor) is exhibited a
picture of Röntgenʼs experimental laboratory
at the University of Würzburg, the Ruhmkorff
coil (the real thing) that he used in his experiments, and pictures of the early times (Photo
13).
Here, there are no personal Röntgen exhibits like those at the Deutsches Röntgen-Museum, but basic matters are thoroughly explained and are definitely worth seeing. If you
have one hour, you will be able to see the
X-ray related exhibits. And after that, if you
walk around and look at the ship, airplane,
locomotive, and automobile exhibits, you will
spend the entire day there. It would also be
fun if you could visit Munich during Oktoberfest (beer festival).

Conclusion

Photo 13: The X-ray-related item exhibits in theDeutsches Museum.

the person who discovered the ʻrayʼ named after him lived in this house from 1919 to 1923.
He died on February 10th 1923.”
After that I went to Isartor from München
Hauptbahnhofto and headed for theDeutsches Museum. Here, is one of the greatest Science and Technology Museums in theworld that was opened in 1925 by Oskar vonMiller. If you were to take your time to lookaround, one day is almost not enough to see

24 ◆ Journal of JART English edition 2015

There are a myriad of purposes for travelling to Germany: Soccer, beer, the ʻfairy taleroad, ʼ the ʻ romantic road, ʼ the Rhine Riversightseeing, and touring the ancient castles. It
would be a blessing to me if this can be used
as a guide for you on your trip to Germany tovisit the footsteps of Röntgen, the one who
cleared the way for radiology.

Reference
1) Michio Yamazaki: The Life of Wilhelm Conrad Röntgen, discoverer of the X-ray, Koukodo, 1989
2) Michio Yamazaki: Wilhelm Conrad Röntgen, the Solitary Scientist, Iryokagakusha, 1995
3) Taiji Aoyagi: The person who opened the door to modern science: Wilhelm Conrad Röntgen and the Discovery of the X-ray, Kouseisha Kouseisha, 2000
4) Tomizo Kato: Illustration: The medical history of radiation, Kodansha, 1994

Arts and Sciences

the original work

Clinical usefulness of the serial ADC analysis in follow-up evaluation
after Gamma Knife surgery for metastatic brain tumors
Kohei Kawasaki, Osamu Nagano, Kyoko Aoyagi, Takahiro Kageyama

the original work

Measurement of anxiety regarding mammography for new radiology technicians-Effectiveness of prescreening trainingAi Watanabe, Kyoichi Kato, Mitsuyoshi Yasuda, Mayumi Aso,
Hisaya Sato, Azumi Isaka, Toshiyuki Takahashi, Yasuo Nakazawa

note

Diagnostic Reference Level (DRL) in the CT of Gunma
Hiroyuki Takei, Hidenori Otake, Yoshito Tsushima, Keigo Endo

Contribution

Development and Operation of an Image Interpretation Training System
Hironobu Tomita

the original work

Fundamental Study of easy decision method for Optimization of Exposure Dosein Computed radiography.
Yasuo Mochizuki, Shinji Abe, Toshiaki Adachi, Masahiko Monma, Kojiro Yamaguchi

material

Actual Conditions of Intervention by Radiological Technologists in the Form of Querying
Doubtful Points in Examining Request Slips from Physicians and Dentists
Yasuo Nakazawa, Masaru Nitta, Chikara Noda, Junya Nakashima, Hisaya Sato, Kyoichi Kato

Contribution

Activities of medical radiologists at a central disaster base hospitalfollowing a major earthquake
Toshiki Tateishi

Arts and Sciences
the original work

Clinical usefulness of the serial ADC analysis infollow-up evaluation after Gamma Knife surgery
for metastatic brain tumors
Kohei Kawasaki1） Osamu Nagano 2） Kyoko Aoyagi 2） Takahiro Kageyama1）1）Department of Radiology, Chiba Cardiovascular Center
2）Gamma Knife House, Department of Neurosurgery, Chiba Cardiovascular Center

Key words: metastatic brain tumor, Gamma Knife surgery, apparent diffusion coefficient, radiation necrosis, tumor re-currence【Abstract】

Magnetic resonance imaging (MRI) is usually carried out in follow-up evaluation after Gamma Knife surgery (GKS)
for metastatic brain tumors. The purpose of this study is to assess the utility of serial measurements of the apparent
diffusion coefficient (ADC) values in differentiating radiation effects from tumor recurrence. We enrolled 57 metastatic
brain tumors (>10mm in maximum diameter) from 51 patients treated with GKS in our institution from February 2011
to September 2012. Diffusion weighted imaging was added to conventional MRI, and the ADC values were measured
every three months at least. The ADC index was defined as the ratio of normalized minimum ADC value in the latest
observation to that of the former observation and was used for chronological evaluation. During follow-up, four
lesions were diagnosed as tumor recurrence. In these lesions, the ADC indices were lower than 1.00 when the tumors
were diagnosed as recurrences. In the cases of good outcome, the ADC indices were higher than 1.00. Based on theseresults, a reduction of the ADC indices between two consecutive exams strongly suggests tumor recurrence. The serial
ADC analysis can be one of the reasonable diagnostic tools to distinguish tumor recurrence from radiation necrosis infollow-up imaging after GKS.

1 Introduction
In follow-up imaging after Gamma Knife
surgery (GKS) for metastatic brain tumors,
several examinations are performed in combination to discriminate between tumor recurrence and radiation necrosis 1-4). Magnetic resonance imaging (MRI) is generally used for amorphological diagnosis. On the other hand,Single-Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET) provide functional imagings andthese are useful for differentiation of tumor
recurrences and adverse radiation effects 2-4).
However, radioisotope examinations such as
SPECT and PET are not available at all of the
facilities and cost much more than MRI.
Hence, in order to diagnose tumor regrowthrationally, we utilized the Apparent Diffusion
Coefficient (ADC) values, which were easily

26 ◆ Journal of JART English edition 2015

obtained by adding Diffusion Weighted Imaging (DWI) to conventional MRI protocol. Since
MRI is simple, widely available and low costtool compared to SPECT and PET, it can betaken as consecutive examination. Goldman
M, et al. 5) reported a useful prognostic measure of tumor response using the ADC values
at the initial post-GKS follow-up. Their study,
however, has a limitation that patients often
underwent follow-up at off-site locations, andthey could not standardize follow-up imaging
protocols. In the present study, we defined aquantitative index of the ADC value (ADC index) for follow-up evaluation after GKS andanalyzed the ADC index chronologically.

2 Materials and methods
This study was approved by institutional review board (IRB) of our hospital (IRB No.

Arts and Sciences • the original work
Clinical usefulness of the serial ADC analysis in follow-up evaluation after Gamma Knife surgery for metastatic brain tumors

363). We took care not to infringe on the patients ʼ right to privacy by making the data
anonymous.
2-1 Patient characteristics
From February 2011 to September 2012, 57
metastatic brain tumors (>10mm in maximum
diameter) from 51 patients were enrolled in
the present study. Patients who underwent
prior radiosurgery and craniotomy were excluded. We also excluded patients with MRI
evidence of hemorrhagic metastases at
pre-treatment. Patient characteristics, tumor
location, and primary cancer are presented inTable. All patients were performed GKS using
the Leksel Model C Gamma Knife (Elekta Instruments AB, Stockholm, Sweden), and underwent consecutive MRI examinations in our
institution.
Table Patient characteristics
Characteristic

Value

Total no. of patients
Men/women
Age (years), median (range)
Tumor location
FrontalTemporal
Occipital
Parietal
Basal ganglia
Brain stem
Cerebellum
Primary cancer
Lung
BreastRectumKidneyEsophagus
Others51
30/21
66 (33-89)
18
6
5
10
3
5
10
34
6
3
3
2
3

2-2 Magnetic resonance imaging
We employed 1.5-tesla MRI system (Achieva;
Philips Healthcare, Best, The Netherlands)
with 8-channel head coil. Conventional MRI
consisted of axial T2 weighted turbo spin
echo, contrast-enhanced T1 weighed fast fieldecho, and coronal contrast-enhanced T1

weighted spin echo sequences.
DWI was performed in the axial plain using
a single-shot spin echo, echo planar imaging
sequence with the following parameters: repetition time = 1886msec, echo time = 68msec,
matrix = 112 × 86, field of view = 230mm,
slice thickness = 6mm, slice gap = 1.5mm,
number of signals averaged = 1, b value = 0
and 1000sec/mm2, acquisition time = 23sec.
The ADC map was computed from the raw
DWI data by use of the standard scanner console software. In addition, contrast enhanced
T1 weighted spin echo image which wassame as DWI for a field of view, a slice thickness and a slice gap was acquired, in order to
set the region of interest (ROI) on the ADC
map (see section 2-3).
2-3 Serial ADC measurements
The ADC values of metastatic brain tumors
were measured every three months at least. A
radiological technologist (K. K) and a neurosurgeon (O. N) set the ROI for each lesion byconsensus as follows. First, we compared contrast-enhanced T1 weighted image to T2
weighted image carefully, and drew the ROI in
the tumor lesion on the contrast-enhanced T1
weighted image which was same as DWI for afield of view, a slice thickness and a slice gap.
Next, the T1 weighted image with the ROI and
the ADC map were displayed side by side, andthe ROI was copied and pasted on the ADC
map. The form of the ROI was modified asnecessary. The minimum ADC values for each
ROI were measured. The ADC value of tumor
was normalized to normal-appearing whitematter. The ADC index was determined as theratio of normalized minimum ADC value in thelatest observation to that of the former observation. In the present study, The ADC indiceswere calculated serially during the follow-up.
The ADC index was regarded as 1.3 whendrawing the ROI was difficult due to tumor
shrinkage (i.e., successful therapeutic response)with reference to the previous report 5).
Arts and Sciences ◆ 27

peripheral dose on each fraction 6). The ADC
index in this case showed typical decrease at
the time of recurrence (Fig. 2 g). At the 2nd
follow-up, the lesion was well-controlled andthe ADC index increased (Fig. 2 b, g). At the
3rd imaging, the reduction in the ADC index
associated with tumor regrowth was observed(Fig.2 c, g). The lesion was diagnosed as a recurrence and retreatment was performed. The
ADC indices were high during next two examinations (Fig.2 d, e, g), but dropped down
again at the 6th follow-up and then the second retreatment was needed (Fig. 2 f, g).
Case 2. This 76-year-old man had 22mm single brain metastasis in the right parietal lobe
from lung cancer (Fig. 3 a). The lesion was irradiated with 22Gy in peripheral dose. At the
2nd follow-up, the ADC index decreased although there was no tumor regrowth (Fig. 3 b,f). As shown in MR images, the intratumoral
bleeding occurred after irradiation in this case(Fig. 3 b). The ADC indices at the 3rd and 4th
follow-up were higher than or equal to 1.00
(Fig. 3 c, d, f), but decreased again to 0.73 at
the 5th follow-up (Fig. 3 e, f). The lesion was

Lesions were diagnosed as tumor recurrence
and closely observed when the following clinical signs were observed: an increase in tumor
size in contrast-enhanced T1 weighted image,a hot spot in Thallium-201 chloride SPECT 2),
and deterioration in neurological symptoms.

3 Results
3-1 Serial ADC measurements
Change of the ADC index in serial follow-up
after GKS are shown in Fig. 1. Among 57 lesions, four cases were diagnosed as tumor recurrence and another two cases needed intensive follow-up. In the lesions that showed
good response after treatment, the ADC indices were higher than 1.00. In contrast, theADC indices were lower than 1.00 when tumor recurrence were suspected.
3-2 Case presentation
Case 1. This 72-year-old man had 37mm single brain metastasis in the left parietal lobe
from lung cancer (Fig. 2 a). The lesion was
treated by three-session GKS with 10Gy in the

2.5

ADC index

2
1.5
1
0.5
0
initial

2nd

3rd

4th

5th

6th

7th

8th

9th

follow-up time
Fig. 1 Change of the ADC index in serial follow-up
Bold lines indicate retreatment cases, and dashed lines indicate intensive follow-up cases. The ADC indices werehigher than 1.00 in the cases that followed good response after treatment, whereas the ADC indices were lower
than 1.00 when we diagnosed tumor recurrence (rhombuses).

28 ◆ Journal of JART English edition 2015

Arts and Sciences • the original work
Clinical usefulness of the serial ADC analysis in follow-up evaluation after Gamma Knife surgery for metastatic brain tumorsgFig. 2 Serial MRIs obtained in Case 1a) Pre-GKS, these images demonstrate a metastatic brain tumor in the left parietal lobe.
b) 2nd follow-up, the lesion showed marked shrinkage and the peritumoral edema subsided. The ADC index
was 2.31.
c) 3rd follow-up, the ADC index decreased to 0.46. The lesion was diagnosed as a recurrence and retreatment
was performed.
d), e) 4th and 5th follow-up respectively, the ADC remained high value (2.39 at 4th and 1.02 at 5th follow-up).
f) 6th follow-up, the ADC index dropped down again (0.29), and the second retreatment was needed.
g) Temporal change in ADC index, the ADC indices decreased to lower than 1.00 when retreatments wereneeded (rhombuses).

diagnosed as recurrence and retreated.

4 Discussion
To differentiate tumor recurrence from adverse radiation effects after radiosurgery is significant clinical issue on patient practical management. Although functional imaging methods including SPECT and PET are useful,these are not routinely available. Meanwhile,the utility of the ADC value in differentiating
between these conditions has been report-

ed 5, 7). Since the ADC value is easily measured
by adding DWI to conventional MRI protocol,
such an image analysis method is suitable for
repeated examinations if it would provide reliable information. We defined the ADC index
and observed its temporal change. The present study aims to assess the efficacy and limitations of the ADC index analysis after GKS
for metastatic brain tumors.
The ADC value reflects the mobility of waterin the tumor. The extracellular water increases
in association with a decrease in the cellulariArts and Sciences ◆ 29

Fig. 3Fig. 3abcChange of the ADC index in case 2
1.5

1

0.5

0
initial

d

e

2nd

3rd

4th

5th

6th

f

Fig. 3 Serial MRIs obtained in Case 2a) Pre-GKS, these images depict brain metastasis in the right parietal lobe.
b) 2nd follow-up, the tumor size reduction was observed, but the ADC index decreased to 0.61. The
intratumoral bleeding occurred after irradiation.
c) 3rd follow-up, the ADC index increased to 1.42.
d) 4th follow-up, the ADC index was 1.00.
e) 5th follow-up, the tumor increased in size, and the ADC index decreased to 0.73. The lesion was diagnosed
as recurrence and treated again.
f) Temporal change in ADC index, note that the ADC index went down to lower than 1.00 when intratumoral
bleeding was observed (circle). Rhombus represents recurrence.

30 ◆ Journal of JART English edition 2015

Arts and Sciences • the original work
Clinical usefulness of the serial ADC analysis in follow-up evaluation after Gamma Knife surgery for metastatic brain tumors

ty of tumor tissue, as tumor cells undergo necrosis or apoptosis due to irradiation 5, 7). Because the ADC value is inversely correlatedwith cellularity, necrotic tissues and cystic lesions have high values 8). In contrast, solid tumors and tumor regrowth indicate low ADC
values. The data obtained in the present study
were consistent with the finding of previous
studies. The ADC indices were higher than
1.00 in the cases of good outcome and werelower than 1.00 when tumor recurrence werestrongly suspected, suggesting that the reduction of the ADC value between two consecutive exams meant recurrence.
Our retreatment case 1 presented the typicalchange of the ADC index in serial follow-up
evaluation after GKS. In the lesion consistingof a solid portion and a component of radiation necrosis, ADC index analysis is particularly effective method for accurate diagnosis ofrecurrent tumor. Our retreatment case 2
demonstrated that the ADC index decreasedin spite of tumor shrinkage. Follow-up MR images revealed the intratumoral bleeding after
GKS in this case. In no signal region on T2
weighted echo planar imaging, the signal is
not detected on DWI with motion proving
gradient owing to the susceptibility effect derived from hemoglobin in the hemorrhagic
portion. Thus, the reduction of the ADC index
might not suggest recurrence in the lesion
with the intratumoral bleeding.
Huang CF, et al. 7) showed measurement of
the ADC value could be used to evaluate thetumor response to GKS. This study, however,
was limited to patients with solid or predominantly solid metastases, in contrast to thepresent study which include cystic, necrotic,
and heterogeneous lesion as well. Thus, theADC index can be applied to miscellaneous
metastases in follow-up evaluation after GKS.
Kano et al. 1) reported a ʻT1/T2 mismatchʼ
method to differentiate tumor progression
from radiation effects by use of T2 weighted
image and contrast-enhanced T1 weighted im-age. Besides, Cha J, et al. 9) found that thepresence of three-layer pattern of ADC was
highly specific for radiation necrosis. The
combined analysis of the ADC pattern with
regional cerebral blood flow may have added
value in the correct differentiation. The methods predicted a radiation induced effect withhigh sensitivity and specificity. By adding serial ADC follow-up to their methods, diagnostic
accuracy may be further improved.
In Japan, The Ministry of Health, Labour andWelfare requires that radiological technologists
should assist physicians in radiographic image
interpretation. In this sense, the ADC index issuitable for an objective evaluation as it has aquantitative value. Therefore, serial ADC
measurements could have potential to be aneffective tool when radiological technologists
advise physicians on diagnostic imaging todistinguish recurrent tumor from radiation necrosis.
The ADC index analysis has several limitations. First, tumor recurrence was defined
only by MRI, Thallium-201 chloride SPECT,
and deterioration in neurological symptoms
without histologic confirmation. Second, thesteroid therapy may slightly affect the ADC
value 6). We generally use steroid medications
for patients with brain metastatic tumors to alleviate neurological symptoms by decreasing
the peritumoral edema. It is necessary to take
into account for the phenomenon in serial
ADC measurements. Finally, the significant reduction of the ADC value is observed in theintratumoral bleeding after GKS, such as inour case 2. Even though the ADC index may
be lower than 1.00 in this situation, it would
be easy to differentiate hemorrhagic lesion
from tumor recurrence when serially evaluated in conjunction with conventional MRI. Although the ADC index analysis has still limitations, it might be valuable tool supporting diagnosis of recurrence in the post GKS follow-up.

Arts and Sciences ◆ 31

Arts and Sciences • the original work
Clinical usefulness of the serial ADC analysis in follow-up evaluation after Gamma Knife surgery for metastatic brain tumors

5 Conclusions
We report the useful method using DWI in
follow-up imaging after GKS. The ADC indices were higher than 1.00 in the cases that
followed good outcome after treatment. For
the recurrent cases, the ADC indices werelower than 1.00. Serial analysis of the ADC index is a reasonable method to distinguish tumor recurrence from radiation necrosis in follow-up evaluation for metastatic brain tumors.
We presented this study in part at the 28th
Japan Conference on Radiological Technologists held in Nagoya, Japan in September
2012, and received a letter of recommendationof the paper submission.
Conﬂict of interest
None.

References
1）Kano H, et al: T1/T2 matching to differentiate tumor
growth from radiation effects after stereotactic
radiosurgery. Neurosurgery, 66, 486-91 (discussion491-2), 2010.
2）Serizawa T, et al: Diagnostic value of thallium-201
chloride single-photon emission computerized

32 ◆ Journal of JART English edition 2015

tomography in differentiating tumor recurrence fromradiation injury after gamma knife surgery formetastatic brain tumors. J Neurosurg, 102 Suppl,
266-71, 2005.
3）Belohlávek O, et al: Brain metastases after stereotactic
radiosurgery using the Leksell gamma knife: can FDG
PET help to differentiate radionecrosis from tumour
progression? Eur J Nucl Med Mol Imaging, 30, 96100, 2003.
4）Te r a k a w a Y, e t a l : D i a g n o s t i c a c c u r a c y o f
11C-methionine PET for differentiation of recurrent
brain tumors from radiation necrosis after radiotherapy.
J Nucl Med, 49, 694-9, 2008.
5）Goldman M, et al: Utility of apparent diffusion
coefficient in predicting the outcome of Gamma Knifetreated brain metastases prior to changes in tumor
volume: a preliminary study. J Neurosurg, 105 Suppl,
175-82, 2006.
6）Higuchi Y, et al: Three-staged stereotactic radiotherapy
without whole brain irradiation for large metastatic
brain tumors. Int J Radiat Oncol Biol Phys, 74, 15438, 2009.
7）Huang CF, et al: Apparent diffusion coefficients forevaluation of the response of brain tumors treated byGamma Knife surgery. J Neurosurg, 113 Suppl, 97104, 2010.
8）Hayashida Y, et al: Diffusion-weighted imaging ofmetastatic brain tumors: comparison with histologic
type and tumor cellularity. AJNR Am J Neuroradiol, 27,1419-25, 2006.
9）Cha J, et al: Analysis of the layering pattern of theapparent diffusion coefficient (ADC) for differentiationof radiation necrosis from tumor progression. EurRadiol, 23, 879-86, 2013.

Arts and Sciences
the original work

Measurement of anxiety regarding mammography
for new radiological technologists-Effectiveness of prescreening trainingAi Watanabe1） Kyoichi Kato2） Mitsuyoshi Yasuda3） Mayumi Aso3）
Hisaya Sato4） Azumi Isaka5） Toshiyuki Takahashi4） Yasuo Nakazawa2）
1）Department of Radiology, Showa University Fujigaoka Hospital. (present: Department of Radiology, Nihon Koukan Hospital)
2）Showa University Graduate school Professor.
3）Department of Radiology, Showa University Fujigaoka Hospital.
4）Showa University Graduate school Instructor.
5）Department of Radiology, Showa University Toyosu Hospital.

Key words: Mammography, Prescreening, New radiological technologist rookie, Training, Anxiety【Abstract】

Since routine mammography has been in the environment performed alone by one radiological technologist (RT) in
many medical institutes, there is much anxiety in respect of diagnostic accuracy. In this study, we evaluated whether
medical anxiety would relieve or not through extracting uneasy elements and forming measure to them.
“Shortage of knowledge required in order to diagnose mammography” became clear as an uneasy element by ourevaluations.
Especially, since it turned out that distinction of mass lesions is difficult, we created the text for exclusive use as
solution and trained RT (2people) by using this.
In results, after this training ability for diagnosing mammography improved 25% higher than that before training, andup to 60% of anxiety complex decreased.
From above our evaluation, “creation of the exclusive text by experienced RT and instruction training by using thistext” were quite effective for uneasy measures in mammography study. And through these training the necessary
knowledge for diagnosing mammography could be obtained and anxiety complex could be relived.

Introduction
Mammography is a specific type of imaging
in which patients are more highly exposed
than in other imaging tests, and routine mammograms have been performed and the images confirmed by a single radiological technologist (RT). “The Survey on Medical Fee”
published in 2010 stated that 49% of additional
mammography imaging was performed “under
the judgment of an RT” 1). Therefore, the ability
to convey an accurate diagnosis is necessary.
Nakayama et al.,2) reported that positioning
errors in mammography imaging may lead tooversights or over diagnosis of breast cancer,
and positioning is, therefore, a critical factor
influencing the accuracy of mammography
screening. Thus, mammography imaging qual-

ity is likely to depend on the ability of the RT.
This ability is often associated with anxiety,especially for new, less experienced RTs.
In this study, we determined the factors underlying uneasiness for new RTs, developedand implemented measures to address thesefactors, and evaluated changes in RT anxiety.

1 Methods
1-1 Equipment used
・Senographe Essential Mammography device(GE Healthcare, Buckinghamshire, UK)・Senographe DS Mammography device (GEHealthcare)・Prescreening report
・Excel 2010 analysis software (Microsoft,
Redmond, WA, USA)
Arts and Sciences ◆ 33

The following 5 steps were followed to determine the cause of anxiety during mammography, to take measures to address those factors, and to evaluate the change in anxiety:(1) factors underlying anxiety during mammography were predicted using the brainstorming technique, (2) the work environment
was examined with respect to each factor, (3)that factors that were unable to be resolved in
the work environment were analyzed, (4)measures were taken to resolve those factors,and (5) anxiety was evaluated with respect tothe implemented measures.
The details of this procedure are described
below.
1-3 Extracting the factors underlying uneasiness in mammography using the brainstorming technique

Two new RTs (hereinafter referred to as
RT-A and RT-B) were encouraged to express
their opinions regarding factors causing uneasiness when performing mammography bybrainstorming3) in which they can freely express their opinions or ideas. In addition to
RT-A and RT-B, an RT with 19 years of experience led the 30-minute brainstorming session.
A diagram of characteristic factors underlying anxiety experienced while performing
mammography is shown in Fig. 1.
We classified the extracted factors into 5 categories: imaging technique, knowledge, device operation, environment, and team medical care.
1-4 Examining the work environment with respect to the extracted factors underlying
uneasinessWe discussed a specific solution for eachfactor.
Anxiety regarding the imaging technique
was resolved by developing a practice protocol that does not involve an actual patient.

34 ◆ Journal of JART English edition 2015

Filmcraft
Photography
for condition
Choice ofthe filter

Knowledge
Necessary forspot shootPositioning

Cooperate with othertypes of job

Medical team

CircumstanceLooking for a
mammary gland
Looking for a mass

Necessary for
expand shootLooking for a
calcification

Alone
Communication
with patients

Everyday check
Check of theWeekend
Check of the end of the month
Maintenance
Procedure of the operation
check

Operation of the machine

Safety to take photograph

1-2 Methods

Fig. 1 Survey for anxiety that occurs during
mammography.

Anxiety regarding team medical care was resolved by implementing active attendance atconferences on mammary tissue or mammotomes and the exchange of opinions
among staff members. Anxiety regarding device operation was resolved by increasing thefrequency of routine inspection or maintenance. Anxiety about the environment was resolved by establishing a system to facilitatecontact between RTs and supervisors. However, no solution was determined to minimize
anxiety related to knowledge; therefore, we
conducted further study on this factor.
1-5 Analyzing the factors causing anxiety thatwere unable to be resolved in the established work environment

Kunugida4) stated that the less knowledge
an RT has, the more anxiety they feel, and improved knowledge is necessary to reduce theanxiety level. In this study, knowledge wasindicated by reading ability, and the feeling ofanxiety and prescreening ability were examined with respect to reading ability.
We analyzed the prescreening ability ofeach RT. The RTs were able to draw a scheme
in the prescreening report, and put a mark in
the appropriate columns for various categories, e.g., mammary parenchyma, calcification,
tumor mass, and other findings (Fig. 2).
Analysis was conducted from July 2010 toMarch 2011. The right and left breast of eachpatient was counted as one case. Before training, RT-A experienced 39 cases and RT-B ex-

Arts and Sciences • the original work
Measurement of anxiety regarding mammography for new radiological technologists -Eﬀectiveness of prescreening training-

Accuracy rate

enced radiologist.
Accuracy rates for mammary parenchyma,classification, tumor mass, calcification, andother findings in the prescreening report are
shown in Fig. 3.
Accuracy rates for mammary parenchyma,classification, and calcification ranged from
50% to 80% for both RT-A and RT-B, but theaccuracy was less than 40% for tumor massfindings. Accuracy rates for other findings
were 0% in RT-A and 36% in RT-B.

Fig. 2 Prescreening Mammography Reportperienced 57 cases. At the first training, RT-A
read 35 cases and RT-B read 55 cases; at thesecond training, there were 40 cases for RT-A
and 50 cases for RT-B; there were 32 cases for
RT-A and 53 cases for RT-B at the third training session. As an analysis method, the prescreening reports created immediately after
reading by both RT-A and RT-B were compared with the reading report created by a radiologist to calculate the accuracy rate. A
proper diagnosis was counted when the classification of mammary parenchyma in the prescreening reports created by both RT-A and
RT-B was consistent with the classification reported by the experienced radiologist. A proper diagnosis was also counted when all findings of calcification such as site, shape morphology, and distribution were consistent withthe findings of the experienced radiologist.
Furthermore, all findings of tumor mass suchas site, shape, marginal, and density were required to be consistent with the findings ofthe experienced radiologist. The presence/absence of all other findings was required to beconsistent with the findings of the experi-

Each Field

Fig. 3 Interpretation report accuracy rate of eachprimary

1-6 Measures to resolve the factors causing
uneasiness that were unable to be resolved in the current work environment

Based on the analysis of the prescreening
results, a textbook was created focusing on
tumor mass owing to its low accuracy rate
(Fig. 4 and 5). This textbook was created using the tumor mass diagnosis flowchart in“Mammography Guideline” 5) by extracting detailed diagnostic components and understandable explanations for terms from sources including “Asunaro Class for Mammography” 6),“ Guide for Breast Cancer Screening using
Mammography” 7), and “Mammography Technical Edition” 8). When a tumor mass is diagnosed, the border/marginal is examined. At
the end of the flowchart, a classification is assigned. Moreover, figures and photographs
were used to facilitate understanding for beginners.
Arts and Sciences ◆ 35

Mammography reading training was conducted on 20 to 40 cases per session using theimages previously taken to accumulate knowledge, and the textbook was used as a reference.
Mass
OverLap of the mammary gland
Shadow local asymmetry (FAD)
CC or MLO come only.
We can write by fine-tipped
pencil edge.
Cleary magical
Have coarse calcifications
within.(Like popcorn.)→Fibroadenoma
Obviously that includes fat.
Category 2

True Mass
Check the boundary edge.
Expand the picture to check.
At first glance edge is visible,
but it looks finely jagged andwhich expand the picture.
Microlobulated

Clearly and smooth mass,
there is no coarse
calcificaions and fat.
Category 3

However, when there is a clear
mass at high concentrations withinfatty breast in the elderly.
Category 4

WithspicularCategory 5

If there is no nucleus
are not clear or when
spiculated.
Category 4

Many breast cancers are classified here.
Edge and breast cancer is to represent theinvasion into surrounding tissues.
Category 4

ary edge of a mass, (3) anxiety about identifying a mass. Each item was scored on a scaleof 1 to 5. A higher score indicates higher anxiety, while a lower score indicates lower anxiety and a gain in confidence. The anxiety experienced when entering the radiographyroom for the first time was rated as 5 points.
RT-A and RT-B were asked to score their anxiety level according to this method. Each of
the 3 items was evaluated.
The correlation between anxiety index andprescreening accuracy was estimated to determine the effect of mammography reading
training on accuracy and anxiety. Spearmanʼsrank correlation coefficient was calculated using Excel software9).

Fig. 4 Text that was created for training

2 Results
2-1 Prescreening ability before and after training

Fig. 5 Text that was created for training. No. 25〜8）

Accuracy rate

The prescreening ability before and after
training is shown in Fig. 6.

1-7 Evaluating changes in the anxiety level
after measures were implemented

Mammography reading training described in
Method 1-6 (hereinafter referred to as training) was conducted 3 times in sessions lasting
4 days. On completion of each training session, the change in the feeling of anxiety wasevaluated.
A questionnaire was developed to calculate
an anxiety index, and it was used to evaluate
the correlation between the change in prescreening ability and the feeling of anxiety.
The questionnaire consisted of following 3
items: (1) anxiety about the classification system, (2) anxiety about determining the bound-36 ◆ Journal of JART English edition 2015

The Number Of Training

Fig. 6 Result about Prescreening

No significant improvement in the accuracy
rate was observed for classification or mammary parenchyma findings after training compared to before training. For calcification, theaccuracy rate of RT-A was 60.6% before training and improved by 10.2% after training, witha rate of 65.5% after the first training, 68.2%
after the second training, and 70.8% after thethird training session. RT-B demonstrated aArts and Sciences • the original work

2-2 The changes in the anxiety index before
and after training

The changes in the anxiety index for the assignment of categories before and after training are shown in Fig. 7. Anxiety indexes of
RT-A and RT-B were 3.5 and 4.0, respectively,
after the first training, and did not differ significantly compared to the indexes before training. However, they decreased to 3.0 for both
RT-A and RT-B after the second training, andfurther decreased to 3.0 for RT-A and 2.5 for
RT-B after the third training; thus, the index
decreased by 0.5 and 1.5 for RT-A and RT-B,
respectively.
The changes in anxiety indexes before andafter training for the boundary edge of masses

The Number Of Training

Fig. 7 Anxiety about the classification of category

Degree Of Anxiety

65.9% accuracy rate before training, and improved slightly but not significantly to 66.7%
after the first training, 68.4% after the second
training, and 69.0% after the third training session.
For the tumor mass field, the accuracy rateof RT-A was 14.3% before training, and increased after training, with an accuracy rate of
25.0% after the first training, 30.0% after thesecond training, and 40.0% after the third
training session. Similarly, the accuracy rate of
RT-B was 37.5% before training, and increased
after training, with an accuracy rate of 40.0%
after the first training, 50.0% after the second
training, and 55.6% after the third training session.
For the other findings, consisting of architectural distortion of mammary glands and focal asymmetric density, the accuracy rate of
RT-A was 0.0% before training and improved
to 12.5% after the first training, 20.0% after thesecond training, and 33.3% after the third
training session. The accuracy rate of RT-B
was 36.4% before training, and improved
slightly to 40.0% after the first training, 44.4%
after the second training, and 41.7% after thethird training session, though these improvements were not significant.

Degree Of Anxiety

Measurement of anxiety regarding mammography for new radiological technologists -Eﬀectiveness of prescreening training-

The Number Of Training

Fig. 8 Anxiety about the boundary edge of mass

are shown in Fig. 8. Both RT-A and RT-B exhibited an anxiety level as high as 5.0 before
training. The anxiety index of RT-A decreased
to 4.0 after the first training, increased to 4.5
after the second training, and decreased to 3.0
after the third training. The anxiety index of
RT-B decreased after repeated training.
The changes in the anxiety index for theidentification of masses before and after training are shown in Fig. 9. Both RT-A and RT-B
exhibited an anxiety level as high as 5.0 before training, and the anxiety index decreased
to 4.5 after the first training, 4.0 after the second training, and 3.0 after the third training
session.
We calculated the Spearmanʼs rank correlation coefficient to test for an association between the prescreening accuracy rate before
and after training and the feeling of anxiety.
The estimated correlation coefficient was r S =0.755 (p < 0.01).
Arts and Sciences ◆ 37

Degree Of Anxiety

5 to 10 for RT-A and 5 to 9 for RT-B, which
represented only approximately 18% of thetotal cases and thus may have had little influence on the observed changes.
Table 1 The Number of cases in each field

The Number Of Training

Fig. 9 Anxiety about the mass or not

A correlation coefficient that is close to one
indicates a strong correlation9); therefore, astrong correlation was observed in this study
between anxiety index and accuracy rate.

3 Discussion
The experience of performing the imaging
test alone and confirming/determining many
types of images is valuable for new RTs. In
mammography, minimizing anxiety is particularly important. In this study, we examined
whether training could reduce anxiety in new
RTs during mammography.
In the training sessions, RTs were required
to determine tumor mass, calcification, andother findings to determine the appropriateclassification. In this study, no significant difference was observed in the ability to determine calcification before and after training.
Tumor mass was considered the most criticalfactor affecting the accurate classification anda significant difference in accuracy was observed before and after training.
The total number of cases and the numberof cases for each classification are shown in
Table 1.
When multiple findings were observed for aparticular case, each finding was counted as
one case. The number of reading cases varied
for each training session, ranging from 32 to
40 cases for RT-A and 50 to 57 cases for RT-B.
The number of tumor mass cases ranged from38 ◆ Journal of JART English edition 2015

Before

Once

Twice

Three Times

Rt.A All Cases

39

35

40

32

Rt.B All Cases

57

55

50

53

Rt.A Mass

7

8

10

5

Rt.B Mass

8

5

8

9

Rt.A
Calcifications

33

29

22

24

Rt.B
Calcifications

41

36

38

29

Rt.A Other
Remarks

8

8

10

6

Rt.B Other
Remarks

11

10

9

12

For tumor mass findings, the prescreening
accuracy rate before training was low. The linear attenuation coefficient for mammary glandand tumor tissue was almost same at 0.80 and
0.85, respectively10), making it difficult to enhance contrast. Therefore, the images could
be difficult to read for new, less experienced
RTs. After repeated training using a textbook
produced for this study consisting of a detailed flowchart, the reading experience pointsof the RT who was not familiar with mammography reading increased, and the accuracy
rate improved by obtaining the improved
reading techniques. It has been reported that
repeated reviews are efficient for the acquisition of memories11); thus, repeated reading
training over a short time span contributed toknowledge acquisition in this study.
For the calcification field, the accuracy rate
was not significantly different before and after
training. This may be because the reading of
calcification was easier than that of otherfields, with a linear attenuation coefficient ashigh as 12.510), which means its contrast ismore intense compared with other mammary
tissues.
For other findings such as architectural distortion and focal asymmetric density, the accuracy rate of RT-A was 0.0% before training,
and improved to 33.3% after the third trainingArts and Sciences • the original work
Measurement of anxiety regarding mammography for new radiological technologists -Effectiveness of prescreening training-session. This improved accuracy may reflect
the initial lack of knowledge for RT-A at the
beginning of the study and the gain in knowledge by repeating training.
RT-A and RT-B showed a similar clinical experience, which was expressed by the change
in the overall accuracy rate in performing
mammography. However, the change in theaccuracy rate of RT-A was bigger than that of
RT-B. RT-B attended a mammography certification test hosted by the Japan Central Organization on Quality Assurance of Breast Cancer
Screening before training; thus, RT-B may
have gained more knowledge on mammography than RT-A. Education via the training sessions was also an efficient way to acquire
knowledge.
The prescreening ability was improved byrepeated reading training while the anxiety index was decreased. The analysis of the prescreening report showed that RT- A and RT-B
lacked experience and knowledge in the tumor mass field. However, they were able togain knowledge efficiently through trainingthat focused on a certain subject. Mihai et al.12)
reported that the more knowledge or a greater depth of understanding were associatedwith a lower level of anxiety. Similarly, acquiring knowledge by reading training may
have led to the decrease in the anxiety levelin this study.
As a training method, a textbook was created focusing on the tumor mass field based ona prior analysis, and its use may have led tothe observed decrease in anxiety. Therefore, it
may be important to understand the weaknesses of the RTs at each institute to create an
appropriate textbook.
The results of this study showed that theprescreening ability of RTs improved by investigating the factors underlying the anxiety
in performing mammography. Koyama et al.13)
reported that a high prescreening ability of
RTs in mammography is important because
the imaging position affects the reading inclinical practice; therefore, training on radiological techniques may have a favorable effecton both RT and patient.

4 Conclusion
Training using a textbook successfully reduced anxiety during imaging experienced bysingle RTs. The importance of the prescreening ability of clinical radiologists was also indicated in this study; thus, we will make aneffort to improve the reading ability by providing additional training in the future.

References:
1) Keiichi Yano et al.: The report of “the Survey on medical fee” of the year 2010. The Japan Association ofRadiological Technologists, 56. 34. 2009.
2) Takashi Nakayama: Improvement strategy of positioning in mammogram. Journal of Japanese Associationof Breast Cancer Screening, 16. 237. 2007.
3) Akira Onuki: Brainstorming technique for meeting. 11–
14, 153–162. Chuokeizaisha Inc., 1989.
4) Naoki Kunugida: Survey on knowledge on radiology
and level of anxiety in nursing student. Journal of University of Occupational and Environmental Health Japan, 30. 421–429. 2008.
5) Choichiro Kido: Mammography guideline. 27–32, 53–
55. Igaku-Shoin Ltd., 2004.
6) Koichi Ishiyama: Diagnostic imaging (supplementaryvolume), Asunaro class for mammography. 32–53.
Gakken Medical Shujunsha Co., Ltd., 2008.
7) Shigeru Hisamichi: Guide for breast cancer screening
using mammography. 69–73, 84–85. Japan Medical
Journal, 2003.
8) Kazuo Ishiguri: Mammography technical edition: 215–
216, 212. Iryokagakusha, 2005.
9) Shinya Yamazaki: Aha statistics and surprising Excel
statistical processing: 41-50, 119–121. Igakuto sho-shuppan Ltd., 2010.
10) Tadaharu Matsunaga: Quite clearly understandable
mammography. 42. VECTOR CORE Inc., 2009. 15.
96–99. 2006.
11) Shigeru Yoshida: Does multiple repetition help learning? Bulletin of Kushiro National College of Technology, 35. 35, 63–66. 2001.
12) Mihai LT, Milu C, Voicu B & Enachescu D: Ionizing radiation-understanding and acceptance. Health Physics, 89. 375–382. 2005.
13) Tomomi Koyama: Significance of prescreening readingby radiation technologist in mammography test. The
Japanese Breast Cancer Society

Arts and Sciences ◆ 39

Arts and Sciences
note

Diagnostic Reference Level (DRL) in the CT
of Gunma
Hiroyuki Takei1），Hidenori Otake1），Yoshito Tsushima2），Keigo Endo3）
1）Department of Radiology Gunma University Hospital2）Department of Diagnostic Radiology and Nuclear Medicine Gunma University Graduate School of Medicine
3）Kyoto College of Medical Science

Key words: DRL (diagnostic reference level), CT (computed tomography), CTDI (CT dose index), DLP (dose length

product)【Summary】

As a regional to take a medical statistics, Gunma Prefecture is one of the region, such as Japan's leading. Thereis 1.7% of the area of Japan, the population is also 1.7%. The number of doctor is 230 persons per 100,000 people,
which is the same as the entire Japan.
The purpose of this study is to derive the diagnostic reference levels (DRL) of CT scan in Gunma prefecture. DRLs
derived from scan parameters of each units were in 75 percentile values, 115.6mGy for head CTDIw and 35.0mGy
for abdominal CTDIw. Compared to DRLs in the EU, values were 1.9 times larger in the head, and were equal to EU
values in the abdomen.

1. Diagnostic Reference Level (DRL)
The diagnostic reference level (DRL) is anindex used in medical imaging to quantitatively analyze the radiation dose received by apatient or the administered radiation (i.e., thequantity of radioactive substances) for a given
imaging method1).
In practice, DRL values are selected basedon percentile scores for the observed radiation dose distribution for multiple patients ora given reference patient. DRL values should
be selected by professional medical groups
working with national insurance and radiation
protection authorities. They should be periodically reviewed at appropriate intervals withrespect to the required stability and long-termchanges in the observed dose distribution. Selected values can be country- and region-specific.

2. Purpose
This study surveyed CT scans performed in

40 ◆ Journal of JART English edition 2015

Gunma prefecture, Japan (in June 2009). We
recorded the number of scans, the scan location, and exposure dose for each scan to determine the exposure dose distributions. We
compared these estimated distributions withpreviously reported DRL values for the European Union (EU)2) . The DRL indices were theweighted CT dose index (CTDIw) and thedose-length product (DLP).
For data sets containing outlier values, we
also considered DRL distributions that excluded outlier values for our comparative analyses.

3. Methods
Questionnaires we sent to all medical facilities in Gunma prefecture that have CT scanners. Respondents were asked to provide information regarding the scanner model andthe standard scan conditions used for adults.
They were also asked to list the age, sex, scan
location, and number of scans received foreach patient scanned in June 2009.
The CTDIw and DLP values for the scanArts and Sciences • note
Diagnostic Reference Level (DRL) in the CT of Gunma

conditions provided were calculated using ImPACT CT Patient Dosimetry Calculator Version
0.99x (see www.impactscan.org). The results
are presented using histograms and the dose
distribution data was used to estimate the DRL
values obtained for each of the CT scanners
in Gunma prefecture. We indicate the DRL
values using histograms of measured values
that show the mean, 25th percentile, and 75th
percentile. We compared these values with
DRL values reported for the EU.

4. Results
We requested information from 193 hospitals(including clinics and other facilities) that had
a total of 198 CT scanners. We received responses from 76 hospitals (39%) with a totalof 81 scanners (41%).
A total of 16,915 patients received CT scansat these hospitals during the one-month period surveyed. We classified scan locations as
the head, face, neck, chest, upper abdomen,
and lower abdomen (pelvis). Many patients

Table 1 Number of patient, CT examination and scanning
women

Total

Number of patient

9,343

7,572

16,915

Number of CT examination

15,287

12,28827,575

Number of scanning

20,917

16,51837,435

Number of CT examinations

men

Age Range(y,o.)Number of CT examinations

Fig. 1 Number of CT examinations for each age range and anatomical locations scanned(for men)

Age Range(y,o.)Fig. 2 Number of CT examinations for each age range and anatomical locations scanned(for women)
Arts and Sciences ◆ 41

received scans of multiple locations in a single
session. Taking these scans of multiple locations into account, the total number of scans
was 27,575. Accounting for multiple scan
types (for example, plain scans and contrast-enhanced scans), the total number ofscans was 37,435. Table 1 and Fig. 1 and 2
show the data for men and women.
Fig. 3 and 4 show the CTDIw and DLP distributions for each scan location.
Tables 2 and 3 and Fig. 5 and 6 show the

Gunma prefecture DRL values, (i.e., CTDIw
and DLP) calculated from these data alongwith the corresponding EU values. The head
and face CT scan results contained clear outlier values, which were excluded from theanalysis.

5. Discussion
The value corresponding with the 75th percentile was used as the DRL value, consistentFig. 3 The distribution of CTDIw for each anatomical locations(The vertical line represents Number of CT examinations, the horizontal line
represents CTDIw (mGy))

42 ◆ Journal of JART English edition 2015

Arts and Sciences • note
Diagnostic Reference Level (DRL) in the CT of Gunma

Fig. 4 The distribution of DLP for each anatomical locations(The vertical line represents Number of CT examinations, the horizontal line
represents DLP (mGy・cm))

Table 2 Diagnostic Reference Level (DRL) in Gunma (CTDIw : mGy)
25%

75%

CT examination

25%

75%

EU

Head

82.1

137.3

60

82.4

115.6

Face

26.9

91.1

35

8.3

50.6

Neck

24.1

39.8

70

­

­

Chest

21.7

31.4

30

­

­

Up Abdomen

25.0

35.0

35

­

­

Lower Abdomen

23.3

37.1

35

­

­

Excluding outliers

Arts and Sciences ◆ 43

with previous studies in other locations. Expressed relative to the corresponding EU values, the Gunma CTDIw and DLP values wereas follows (respectively): 1.9 and 1.4 for headscans, 1.5 and 2.4 for face scans, 0.6 and 1.1

for neck scans, 1.1 and 0.7 for chest scans, 1.0
and 0.7 for upper abdomen scans, and 1.1
and 1.2 for lower abdomen scans.
While the CTDIw and DLP data for nearly allscan types meet the EU DRL standards for

Table 3 Diagnostic Reference Level (DRL) in Gunma (DLP : mGy・cm)
25%

75%

CT examination

25%

75%

EU

Head

955.5

1662.3

1050

963.9

1505.9

Face

337.5

926.1

360

345.5

849.8

Neck

292.8

520.9

460

­

­
­

Excluding outliers

Chest

251.3

475.3

650

­

Up Abdomen

290.2

529.8

780

­

­

Lower Abdomen

304.1

653.2

570

­

­

Fig. 5 Diagnostic Reference Level (DRL) in Gunma (● : EU)

Fig. 6 Diagnostic Reference Level (DRL) in Gunma (● : EU)

44 ◆ Journal of JART English edition 2015

Arts and Sciences • note
Diagnostic Reference Level (DRL) in the CT of Gunma

chest and upper/lower abdomen scans, theobserved exposures for head and face scans
were significantly higher than the EU standards, ranging between 1.4 and 2.4 times theEU values even when clear outliers were excluded.
The Japan Association of Radiological Technologistsʼ 2006 X-ray guidelines for adult CT
scans3) set a CTDI value of 65 mGy for headscans and 20 mGy for abdomen scans (equivalent to 22 mGy for 32-cm diameter acrylic
phantom). Our results were between 1.6 and1.8 times higher than either of these values.
CT scans with higher patient exposure doses
usually have better picture quality, so the excessive values observed for Gunma prefecture
facilities relative to those of EU facilities does
not directly imply that these doses are inappropriate. They may be necessary to create
the picture quality demanded.
Since the EU DRL standards were set in
1999, they are now over a decade old andmay not reflect current conditions. However,a recent survey of DRL values for CT scans in
Korea4) found a CTDIw of 62.4 mGy for headscans, showing that many scanners have DRL
values lower than those of the EU.
Moreover, the large number of unusable responses we received indicated that we did notadequately communicate the purpose of thequestionnaire or the directions for participation, so additional, improved survey methods
will be needed in the future. One factor that
affected the survey results was the calculation
methods, which were based on summary statistics that did not account for individual variation. While many different patient conditions
exist in practice, each calculated value wasobtained from a single scan condition for asingle scanner and scan location. Estimating
exposure doses according to each set of patient conditions will result in more reliable results in the future.
Defining the DRL as the 75th percentile value, as is done overseas, enables the determi-

nation of an index value purely for the purpose of reducing exposure; however, we believe that considering both the 25th and 75th
percentile values is needed to balance exposure reduction and picture quality requirements.

6. Conclusion
We determined the CTDIw and DLP values
and therefore the DRL for CT scanners inGunma prefecture in 2009. We presented boththe 25th and 75th percentiles for DRL.
We found that chest and upper/lower abdomen scans were similar to those reported in
the EU, but values for head and face scans
ranged from 1.4 to 2.4 times higher. The effects of survey method, facility differences,educational differences, and other factors are
topics that will require detailed studies in the
future.

7. Acknowledgments
This study was assisted by the ʻEndo Teamʼ
Grant-in-Aid for Cancer Research provided by
the Ministry of Health, Labour and Welfare.
We would also like to express our sincere appreciation for the efforts of the staff and technicians at Gunma prefectureʼs medical facilities with CT scanners.

References
1) ICRP supporting guidance 2. Diagnostic reference
level in medical imaging, review and additional advice,
ICRP committee, 2002.
2) Quality Criteria for Computed Tomography. EUR
16262, EC, 1999.
3) Suzuki Shouichi: Hōshasen shinryō ni okeru Senryō no（2）
Teigen mokuhyō chi“Iryō hibaku gaidorain 2006”
CT, JJART54（1）: 33-46, 2007（Japanese）
4) Cho PK, Seo BK, Choi TK, Kim JS, Kim YH, Choi
JH. The development of diagnostic reference level on
patient dose for CT examination in Korea. Radiat Prot
Dosimetry 129:463-468; 2008

Arts and Sciences ◆ 45

Contribution

Development and Operation of an Image Interpretation Training System
Hironobu Tomita
Saitama Association of Radiological Technologists

1. BackgroundOn April 30, 2010, Health Policy Publication
No. 0430, "Concerning the promotion of team
medicine by means of cooperation and collaboration between medical staff" was issued by
the Ministry of Health, Labour and Welfare. Its
basic concept is that "In order to provide
high-quality medical care alongside patientsand their families that utilizes the expertise of
specialized medical staff, it is important to refer to the general instructions issued by doctors and others, with the medical staff sharing
a common objective and information as ateam, proactively contributing their own specialist skills while increasing the level of collaboration and complementation between
them." Our role as radiological technologists
is expanding in terms of taking on tasks in areas including radiological treatment, tests, andmanagement, as well as imaging tests. As specialists in these tasks, this means that we may
be able to play increasingly major roles inclinical settings. In terms of the proactive utilization of clinical radiological technologists,
two tasks will be required: assisting with theinterpretation of diagnostic images and providing explanations and advice concerning radiological tests.

46 ◆ Journal of JART English edition 2015

2. History of Image Interpretation
Training by the Saitama Association of Radiological Technologists
The Saitama Association of RadiologicalTechnologists has been engaged in image interpretation training and content production
for more than a decade, and has made thesewidely available to its members through seminars and other means. We have also held
film-reading contests at the Saitama Radiology
Conference, initially by setting up an area fordisplaying and interpreting films on mammography and upper gastrointestinal scans on afilm viewer. Ultrasound interpretation using a
poster format was subsequently added andsince 2006 the display has also included X-ray
CT scans. This involves using a laptop computer to manage DICOM images and a viewer
on a single CD-R using a program developedby our group, a standalone program for individual computer users and the first to provide
a monitor-based image interpreting environment.
We are also developing a system to certify
radiological technologists. At present, theSaitama Association of Radiological Technologists offers certification in chest X-rays, uppergastrointestinal scans, and X-ray CT scans.
The system was launched in 1999 with threemodalities: chest, upper gastrointestinal, andmammography. Recent trends mean that it isContribution
Development and Operation of an Image Interpretation Training System

now possible to take the Common Examination of the Central Committee on Quality Assurance of Breast Cancer Screening in regional
centers, and for this reason the 3 modalities
now comprise chest, upper gastrointestinal,and X-ray CT (added in 2009). The certification standards for each modality are listed below. When the scores for tests of interpretation, notation, and image evaluation (for theupper gastrointestinal modality only) differ,the lower score is used to decide the certification grade. For example, a candidate with ascore of 95 points for interpretation and 73
points for notation would be certified as
Grade B, and a candidate who scored 80
points for interpretation, 90 for notation, and60 for image evaluation would be certified as
Grade C.
Certification Standards
Chest

Grade A: 90 points or above in both sections (interpretation/notation)
Grade B: 70–89 points
Grade C: 69 points or less
X-ray CT

Grade A: 90 points or above in both sections (interpretation/notation)
Grade B: 70–89 points
Grade C: 69 points or less
Upper gastrointestinal

Grade A: 90 points or above in all sections(interpretation/notation/image
evaluation)
Grade B: 75–89 points
Grade C: 74 points or lessTo qualify for certification, candidates must
be competent in interpretation as well as innotation, and will not be certified if they do
not score above the requisite standard in bothareas. This is based on the idea that in addition to thorough familiarity with the device

and quality control, interpretation is an essential skill to determine the quality of clinicalimages in order to provide images that areclinically useful. We have already conducted
seminars and certification tests that are directly related to clinical tasks. Several clinical radiological technologists take these tests every
year. Certified radiological technologists areissued with an individual certificate of certification, and their names and affiliations are
published (with their permission) on the website of the Saitama Association of RadiologicalTechnologists. Please see http://www.sart.jp/
member2005/ for more details.

3. Development of a new image
interpretation training system
In recent years, more hospitals have moved
to filmless, monitor-based diagnostics, and thenecessity for a new image interpretation training system has become apparent. Image interpretation is a skill for which training is mostwidely needed for radiological technologists
and previous systems that used film viewers
entailed significant cost and labor in terms ofhandling, preparation, and other tasks. Thesemethods also presented major challenges withregards to the deterioration of teaching films
over time and handling. Recent years havealso seen dramatic advances in the use ofelectronic clinical image data, and it was suggested that developing this system would enable the use of mammography, upper gastrointestinal, CT, and chest X-ray scans. We began
development jointly with Doctor-NET, a remote diagnostic imaging company, in June
2012. The basic concept was to develop a system that could provide a reading environment
on a regular monitor and which could be
used at conferences and other events nationwide, with simplification and streamlining ofcontent production and operability taken into
consideration.

Contribution ◆ 47

4-1. System Overview
In light of the above, we developed the system illustrated in Fig. 1. Its characteristics canbe outlined as follows. Image data for interpretation can be uploaded to a cloud-based
server as raw DICOM data by each workshop
leader. As long as internet access is available,
the leader can upload images from anywherein Japan. This improves operating efficiency
and enables teaching files to be managed online. An application virtualization system isused to distribute the images to client computers at conference venues and elsewhere,
meaning that the DICOM images themselves
are not downloaded. This reduces the amountof bandwidth required, ensuring fast responsiveness on any terminal. The recommended
minimum transmission speed between theserver and client computers is around 10Mbps.

4-2. Virtualized application
Fig. 2 shows an outline of the system. Thisis an image forwarding-based application using an environment based on Windows terminal service (TS) and remote desktop service(RDS), with enhanced security, performance,
extensibility, stability, and flexibility, among
other advantages. The major advantage of thissystem is that the desktop application and client software that earlier had to be installed on
the client terminal before use, are installed
and run on the server, with only the application's screen images displayed on the desktopof the client terminal. The user operates thesoftware remotely by using a keyboard andmouse. An environment is thus created inwhich the application is completely virtualized, just as if it were being operated on theclient terminal. This clear separation of theenvironment in which an application is run
from that in which it is used is a key featureof virtualization. It has a range of advantages,
including enabling the uniform managementof the client environment, assuring security bymeans of functions such as Secure Socket Layer (SSL) or a Virtual Private Network (VPN),
eliminating the need for a dedicated thin client terminal and guaranteeing ease of operation to a certain extent, even if network connections are not optimal. Security is extremely
important for medical images and as data arenever copied onto a client terminal they canbe aggregated and protected at a single location. The fact that the application is virtualizedalso means that installation and maintenanceare performed on a single server, enabling instant delivery to the user, reducing the amountof management required and dramatically improving the flexibility and speed of response

Application virtualization technology

Uploading of cases
Personal data in DICM data are masked in advance,
but can also be masked on the server if necessary

Cloud-based server(Doctor-NET)
Recommended connection speed at least
10 Mbps
Mammography, uppergastrointestinal, chest CT, and plain
chest X-ray scans
From the organizer’s computer (athome or in a hospital)

As application
applicationAs
virtualization is used,
DICM data are notforwarded to theclient terminal,
reducing the
restrictions imposedby connection
connection speed.

Can also be used over WiFi at the venue

Server application
Web application

ServerFig. 1.

48 ◆ Journal of JART English edition 2015

Application run on server

The user uses the server
software for remote operation

Can be viewed from a PC used
to conﬁgure the settings
Image interpreting set up as desired at the venue (conference, seminar,

Complete virtualization of
application
Client software installed and run on
the server

Client computer terminal

Fig. 2.

Contribution
Development and Operation of an Image Interpretation Training System

of information technology.

4-3. Steps to create questions
Actual case registration can be performed
by uploading to the server from a personal
computer, on which the settings have alreadybeen made. When uploading DICOM data,
ideally a rewritten version of the patient's personal information should already have been
uploaded, but if this is not possible then personal information can be masked after uploading through a simple operation. Fig. 3
shows the sequence of operations. Large
numbers of cases can also be uploaded to theimage server, and packages can easily be created or selected for use at conferences, seminars, or other events. Fig. 4 shows the sequence of operations for the easy creation ofquestions on interpretation.

Image tag editing tool

Participants engaged in image interpretation

Photograph of the answer sheet

5. Initial use

Edit the DICOM tags for external data ID or errors in patient data

Select the test to bechanged

File ＞ Click on Edit Tag (T)Launch editing tool
Input the value to be changed with the character レ inthe box to be edited
Click on “Replace” and click “OK” on the conﬁrmation
screen.

“Replacement Status” screen showing the replacement in process
When the screen showing the replacement status shows the“Replacement Complete” window, click “OK” to complete thereplacement.

Fig. 3.

Creation of image interpretation
packages(1) Select the type ofscan for which you wish
to create a new package(3) The conference screen will be
displayed, with the type of scan you
selected in step (1) added as a new
package.
(4) Change the name of the
package.

(2) Right click on the list.
Select “Add to package”
from the pop-up menu.

The 2012 Kanto Koshinetsu Clinical Radiology Conference was held in Ibaraki Prefecture
on October 6th and 7th, 2012. During the conference, 10 cases each, of chest CTs, plain
chest X-rays, upper gastrointestinal scans, andmammography scans were prepared to allow
for interpreting experience, and the monitor
interpreting environment was used for the firsttime. Three devices were set up for viewing
CT images, 2 for plain chest X-rays, 3 for upper gastrointestinal scans, and 2 for mammography scans. The participants filled in theirfindings on an answer sheet while viewing
the images on the image viewer and were
provided with the correct answers after they
had finished. The event was very popular,
with over 70 people participating over the
2-day period. Photographs taken on the day
are reproduced below.

Fig. 4.
Contribution ◆ 49

Upper gastrointestinal
case

3, 8% 2, 5%

1, 2%
1, 2%

3, 8%

¼k½
ÁÈÅ（year）

9, 24%

ÆÈÁÀÁÈÅ ¼k½

3, 8%
9, 24%

9, 24%

ÁÁÈÁÅ
ÆÈÁÀ

11, 29%ÁÆÈÂÀ
ÁÁÈÁÅ

9, 24%

11, 29%3, 8%ÂÆÈÃÀ
ÂÁÈÂÅ
ÃÁÈÃÅ

Fig. 5. Number of years of experience of technologists who took part in image interpretation.

«NE
Person
«NE

5

4

8
7

1

6

X
21 Easy

5

3
4
2
3
1
2
0
1
0

6
Percentage of

5

cxlI
1 completion
low

4

2
3 Ordinary
²

3

4

2
1
0

Percentage ofcxl»
5 completion
high

CT

MMG

UGI

=0@2*
modality

Chest
X Ray
¤µ

Fig. 7. Extent of completion of image interpretation
viewer by modality (including speed).

867ÂÁÈÂÅ
ÁÆÈÂÀ
ÃÁÈÃÅ
ÂÆÈÃÀ

7

Ya s u o N a k a z a w a , P re s i d e n t o f t h e J a p a n
Association of Radiological Technologists, also
had a go at image interpretation!
Right: Koichi Horie, Vice-President of the Saitama
Association of Radiological Technologists.
Writing: Yasuo Nakazawa, President of the Japan
Association of Radiological Technologists

PersonE

2, 5%

Chest X-ray caseX

32  ²

CT

MMG

UGI

CT

=0@2*MMG
UGI=0@2*
modality

¤µ

43

²
Ordinary

54

¹

5

¹ cult

Difﬁ

¤µ
Chest
X Ray

Fig. 6. Degree of difficulty by modality.

6. Questionnaire for participants
The results of a questionnaire completed on
the day by participants who attempted the interpretation questions are shown below. As
shown in Fig. 5, approximately half of the ra-

50 ◆ Journal of JART English edition 2015

diological technologists who took part had
less than 10 years of experience and interest
was greater among younger technologists thanthat among veterans. As shown in Fig. 6, level
4 was the most common level of difficulty
across all the modalities and many participants expressed the opinion that the questions were difficult.
As shown in Fig. 7, an evaluation of 3 wasgenerally appropriate in most cases and thefact that no participant achieved an evaluationof 4 or 5 for mammography scans alone canbe explained by the fact that the internet connection speed was only 8 Mbps, meaning thatthe response time for W.W adjustment andContribution
Development and Operation of an Image Interpretation Training Systemzooming in and out was poor. This result correlates with the developer-recommended
speed of 10 Mbps and would improve with abetter connection speed.

Acknowledgments
We would like to express our gratitude to
the staff of Doctor-NET, the company involvedin the joint development of this system.

7. Conclusion
In this article, I have described the training
in image interpretation offered by the Saitama
Association of Radiological Technologists, its
development, and its attributes as a new initiative. We intend to make every effort to contribute to further improving the image interpretation skills of clinical radiological technologists in future. The photograph below showssome of the members involved in implementing this new initiative.

Top row, left to right: Yosuke Kidokoro, Kiyoshi
Ogawa, Koichi Horie, Hiroshi Tanaka, Kan
Yokoyama.
Bottom row, left to right: Hironobu Tomita, Satomi
HashimotoContribution ◆ 51

Arts and Sciences
the original work

Fundamental Study of easy decision method for
Optimization of Exposure Dose in Computed
radiography.
Yasuo Mochizuki1） Shinji Abe2） Toshiaki Adachi3） Masahiko Monma2） Kojiro Yamaguchi4）1）Department of Radiological Technology, Faculty of Health Sciences, Nihon Institute of Medical Science.
2）Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences3）Department of Radiology, University of Fukui Hospital
4）Faculty of Radiological Technology, Fujita Health University School of Health Science

Key words: computed radiography (CR), Wiener spectrum (WS), root mean square (RMS), exposure dose, threshold【Abstract】

The optimum dose for a computed radiography system (CR) was estimated from the relationship of the radiationdose to the root mean square (RMS) and the Wiener spectrum (WS).
Samples for analysis of noise characteristics were prepared using a 50.0 mm tough water phantom, as a scatteringbody, fitted with a 20.0 mm Al filter (SID 200 cm, tube voltage 80 kV). The dose level at which the film density inthe standard screen-film system was 1.0 ± 0.05 was adopted as the criterion dose (23 mGy) and five samples wereprepared at dose levels of 1/4, 1/2, 1, 2 and 4 fold relative to the criterion dose.
RMS was calculated from five 256 × 256 pixel images. WS was determined from the 320 segments yielded by twodimensional fast Fourier transformation (2DFFT) of the 256 × 256 pixel images.
On the basis of the data on RMS and WS, the optimum dose was determined, with the threshold level defined as thepoint of intersection in linear approximation between the low dose range affected by the quantum mottle and the highdose range depending on the system noise. As a result, the dose for CR, determined from RMS and WS, was about
30% lower than the screen-film system criterion dose.

Introduction
The digitization of X-ray systems and general imaging devices has led to a shift from intensifying screens and the screen-film system(S/F system) to computed radiology (CR),flat-panel detectors (FPDs), and other types ofdigital radiography (DR).
The imaging conditions of the S/F system
require that the operator select the sensitive
material based on the site to be imaged, making its sensitivity the decisive factor. However,
DR obtains accurate density using automaticcompensation mechanisms. Thus, unlike the
S/F system, DR has no concept of sensitivity
as an important factor to match the imaging
conditions1). As a result, although the X-ray
imaging conditions are assumed to be basedon standard doses used in the S/F system, no52 ◆ Journal of JART English edition 2015

systematic method of setting appropriate imaging conditions exists, which makes the determination of imaging standards difficult. An
ICRP report2) has pointed out the problem ofhigher doses being used for DR X-ray imaging
than those used for the S/F system, and thestandardization of imaging conditions is being
attempted.
Comprehensive evaluations of the S/F system based on physics have been carried out
using the noise equivalent quanta (NEQ)3)
w hich is the squared signal-to-noise ratio(SNR). Since there is no sensitivity index for
DR, it has been proposed1) that the detective
quantum efficiency (DQE)4), which is the ratioof the squared output SNR and the squared
input SNR, be used.
DQE is obtained using the ratio of the average number of photons absorbed per unitArts and Sciences • the original work
Fundamental Study of easy decision method for Optimization of Exposure Dose in Computed radiography.

area for the purpose of forming an image on
the DR device and the number of incident
photons, which reveals photon detection efficiency. In an ideal imaging system in which
all the incident photons are used for image
formation, DQE would be 1. Thus, the noisecharacteristics directly affected by an imaging
dose according to the NEQ denominator may
be useful as a factor for determining DR imaging conditions. However, there are no studies
one the investigation of a method for determining the imaging dose according to the root
mean square (RMS) and W iener spectrum(WS), which are used as indices to evaluate
the incident dose and noise characteristics.
The authors have proposed an estimator todetermine the imaging dose that estimates thethreshold from the relationship between thevisual evaluation method, known as the image
quality figure (IQF)5,6), and the CR exposure
dose (hereafter referred to as imaging dose)7).
However, it has been difficult to prepare specimens for visual evaluation and analyze experimental observations.
The present study focuses on the relationship between imaging dose and noise, and reports on our investigation into a simple method for determining the CR imaging dose withthe threshold level for the optimum dose for
X-ray images with a good balance between
image quality and dose. This balance point isdefined as the point of intersection in linear
approximation between the low dose range
affected by the quantum mottle and the highdose range that depends on the system noise.
We also performed visual evaluations of the
S/F system and CR image quality by calculating the detection ability of the area under the
curve (AUC) of the receiver operating characteristics (ROCs) using the S/F system and CR
hard copies (film) created according to the S/
F system imaging dose standards using acrylic
bead signals.

1. Imaging dose and noisecharacteristics
NEQ was defined as the output (SNR)2 value, and DQE was defined as the ratio between
input and output (SNR)2 values using the following formulas:(log e) 2 ! G 2 ! MTF (u) 2
NEQ(u ) = (log10 e) 2 ! G 2 ! MTF (u) 2
10
WS (u )
NEQ(u ) =WS (u )

(1)(log e) 2 ! G 2 ! MTF (u) 2
DQE (u) = (log10 e) 2 ! G 2 ! MTF (u) 2
10
q ! WS (u)DQE (u) =q ! WS (u)(2)

In these formulas, u is spatial frequency,(log10e) is the density conversion coefficient,
G is the gradient, and q indicates the average
number of incident photons per unit area. The
WS of the quantum mottle was provided by
the following formula8):(log e) 2 ! G 2 ! MTF (u ) 2
WS (u ) = 10
n

(3)

—

In this formula, n indicates the average number of X-ray photons absorbed per unit area.
—
When WS (u) is taken to be granularity, 1/n. tobe sensitivity, (log10e) G to be contrast, andMTF(u) to be sharpness, it can be expressed as
Granularity =sensitivity × contrast2 × sharpness2(4)

Therefore, the DR X-ray imaging dose canbe estimated from noise characteristics bytreating the number of incident photons as anindex that corresponds to the sensitivity of the
S/F system.

2. Experimental Methods
2-1 Experiment plan and sample preparation

The experiment plan for WS measurement
according to radiation quality8) standards established by the Bureau of Radiological Health(BRH) and sample preparations for ROC analysis is shown in Fig. 1. The X-ray generator
used was a KXO-80G (Toshiba Medical Systems Corporation) and the CR used was a ReArts and Sciences ◆ 53

was 90 s, and the development temperature

X-ray tube

was 33.5 °C.

Aｌ Filter(20 ㎜)

SID:200 ㎝

ChamberTough water

5.0 ㎝
Cassette

Fig. 1 Experimental layout of noise measurements using tough water.

gius Model 170 (Konica Minolta Inc.). The distance (source-to-image distance: SID) between
the focus and the stimulable phosphor plate(hereinafter referred to as plate) was 200 cm.
Tough water manufactured by Kyoto Kagaku
Co., Ltd. was used as a scattering body (350 ×
350 × 50 mm) and was set above the plate,
and the measurement samples were imaged.
Digital imaging and communication in medicine (DICOM) specification output images
were output as straight line gradients without
frequency processing or other types of processing.
The standard dose was determined using an
SRO 250/SRG (Konica Minolta Inc.) fitted witha 20.0 mm Al filter on the X-ray tube side on
the S/F system sensitive material. It was thesurface dose (air kerma) for an X-ray tube
voltage of 80 kV, an X-ray tube current of 100
mA, and an imaging time of 0.140 s obtained
for a film density of 1.0 ± 0.05 as measured bya diffusion densitometer (Konica Minolta Inc.).
W e obtained an average value of 23 µ Gy
(0.69µ C/kg) from 5 irradiations of the incident
dose on the surface of the tough w ater asmeasured using the NERO ™ mAx Model 8000
(VICTOREEN). This surface dose was used as
the standard (criterion) imaging dose. The automatic developer used was the Konica Minolta SRX-503, the development processing time

54 ◆ Journal of JART English edition 2015

Using the criterion dose as a reference
point, we created five samples with imaging
times of approximately 1/4 (6 µ Gy), 1/2 (12 µGy), 1 (23 µ Gy), 2-fold (47 µ Gy), and 4-fold(95 µ Gy). Doses were the average of thesefive. Two types of samples were used: thosewith a standard pixel size (ST: 0.175 mm) andthose w ith a high-quality pixel size (HQ:
0.0875 mm). We created five images for eachof the pixel sizes and for each of the samples
by using the same imaging conditions. This
yielded a total of 50 DICOM image samples
with noise measurements.
2-2 Measurements of noise characteristics
2-2-1 Measurements of RMS granularity

Noise measurements (DICOM images) wereconducted using the free image processing
soft w are Image J. The calculation range of
RMS granularity we used set the region at thecenter of the display screen that was 256 × 256
pixels as the region of interest (ROI). The 50
ST and HQ images in this range were calculated using Image J to derive RMS granularity.
The RMS calculation formula w e used isshown below:
RMS =


1 n n
!! (PVi, j " PV) 2 
 i =1 j =1

(5)

In this formula, n is the number of data—
items, PVij is the pixel value, and, PV is average pixel value.
2-2-2 WS measurements
W S measurements w ere conducted using
two-dimensional fast Fourier transformations(hereinafter referred to as 2DFFT) 9) w hichwere in accordance with International Electrotechnical Commission (IEC) standards, on uniformly irradiated DICOM images. We set thecalculation range of 2DFFT to one segment(hereinafter referred to as SEG) of the 256 ×
256 pixel image within the ROI. Trend correction for this region was set to calculate two-di-Arts and Sciences • the original work
Fundamental Study of easy decision method for Optimization of Exposure Dose in Computed radiography.

mensional quadratic-approximation images
according to the Legendre polynomial andcorrected for the amount subtracted from theoriginal image. The input/output characteristics of these images, which are indicated in
the formula below, were then calculated in
the log system (CR) using 2DFFT.
5

2
1!x!y 1 M
WS !E (u j , vk ) = 2
DFT 2 D {!PVm ( x s , yt )}
"
2
N
N
M
G
(log
e
)
m #1
x
y
10
E

(6)
In this formula, Δ x Δ y indicates pixel size,
Nx Ny is the number of data items set within
the ROI, M is the number of segments, DFT 2D
is the two-dimensional discrete Fourier transform, and Δ PV is the variation component of
the pixel values.
WS values used in our assessment were theaverage of 64 SEG for each sample, with a total of 320 SEG from five samples additionallyaveraged. Frequency bins were calculated using 14 sequences (excluding those above theaxis of W S spatial frequency [u, v] on thetwo-dimensional distribution), with bin width
calculated at approximately 0.114 cycle/mm
for ST and at approximately 0.229 cycle/mm
for HQ. Digital WSΔ E/E in formula (6) was calculated by linearizing the exposure conversion using G2・(log10e)2 in the denominator on
the right side of the equation in the exposure
conversion and calculating the dimension of
the X-ray quantum. Thus, NEQ (u) and DQE(u) for the digital system were calculated informulas (1) and (2) with the conversion coefficient (log10e)2・G2 in the numerator on theright side of the equation removed.
2-3 Estimation of imaging dose using WS

It has been reported that the noise characteristics in the S/F system correspond to the
WS value of the 0.1–0.5 cycles/mm low spatial
frequency range in terms of visual assessment8,10). Thus, we estimated the threshold forthe optimization of the imaging dose from theaverage WS value at the minimum spatial fre-quency, which is determined by the reciprocalof the product of the number of data items
and pixel size, and the imaging dose.
2-4 Creation of samples and observation
method for ROC analysis
2-4-1 Creation of samples for ROC analysis

Samples for use in ROC analysis were created in the same way as the WS samples. A single sheet of film was divided into 30 parts bypunching 30 holes in a 20 × 35 [mm] grid pattern on a copper plate measuring 254 × 305[mm] and 0.1 [mm] thick7). Acrylic beads ⏀ 2.0
mm were placed randomly in 15 of the 30
holes. Data from 15 beads with signals and 15
beads without signals for each sheet of film
were then collected.
ST and HQ observation samples for the S/F
system and CR totaled 120 data items for 60
beads with signals and 60 beads without signals. The placement of the beads was thenchanged for each of the 4 sheets of film for a
total of 12 sheets of film providing data. The
standard SRO250/SRG was used to obtain datafrom the S/F system. Hardcopy (film) CR images used for ROC analysis were processed asfollows. The DICOM standard default window
width (2047) and window level (4096) pixel
values were selected on the Regius Model 170,
and the linear gradient of LIN-01 was selectedfrom the lookup table without performing frequency processing. A film density of 1.00 ±0.05 was output for all actual size ST (0.175mm) and HQ (0.0875 mm) images by using
the dry imager DRY-PRO 752 (Konica Minolta
Inc.).
2-4-2 Observation experiment for ROC analysis
Observations were carried out by six students who had been trained to read observation samples.
Regarding the data obtained from the experiment, rules have been established for publishing the results and using the results as aresource for educational material, and theconsent of the observers have been obtained.
Arts and Sciences ◆ 55

56 ◆ Journal of JART English edition 2015

analysis of variance performed using the DBM
method included the following variance components: inter-system (T), inter-observer (R),inter-sample (C), system-observer (TR), system-sample (TC), observer-sample (RC), system-observer-sample (TRC), and total (Total).
Two-tailed paired t-tests were used to rate
the statistically significant difference between
two groups (S/F system and ST or HQ, and ST
and HQ), in order to ensure that redundancy
did not affect the results.

3. Measurement results
3-1 RMS granularity and imaging dose
We calculated RMS for the approximately

6,600 pixels set as the ROI of the 256 × 256
pixel images for each sample. The average
RMS value for the approximately 33,000 pixelsof the five samples was obtained using RMS
calculations. The results are shown in Fig. 2.
The RMS value for ST and HQ images sharply
decreased as dose increased in the low-dose
region, but gradual decreases were observed
at high doses near the criterion dose of 23 µGy.
3-2 WS and imaging dose
Fig. 3 and 4 show the results for the hori-zontal (scan) and vertical WS calculated for a
total of 320 SEG from both ST and HQ images

10.00
8.00

RMS

As points of note prior to the actual observation, we requested the observers that whenviewing from the direct viewing angle, theyshould not compare the hole under observation with any of the other 29 holes in the sample, and especially not the 8 to the top, bottom, left, and right in the immediate vicinityof the hole under observation. The observation distance and duration were freely determined by the observers themselves. They observed the samples in order without any particular restrictions. Considering the influenceof the learning curve effect, we presented thesamples in a different order for each observer
and took into consideration the order effect.
Ratings for certainty were given using the continuous certainty factor method with 50 points
set as the maximum.
Film images were read in the following environment: viewing screen was placed so that
it would not be influenced by outside light.
We measured the light in a room with normally used lighting by using a luminance meter(Konica Minolta Inc., LS-100), and obtained an
approximate value of 57 cd/m2. The brightness of the vie w ing screen (Moriyama, for
X-ray use: CH5K) front panel was measured tobe approximately 2,600 cd/m2.
2-4-3 Rating AUC average values
Rating of the average values for the detection ability of ROC analysis (AUC) was performed as follows. Standard deviation was calculated from the variance between the observers using the paired t-test on both sides to determine the difference in the average values.
Then, we used the Jackknife method to assess
the standard deviation of the estimator because this method removes the influence ofvariance that occurs between observers andbetween samples from overall error variance.
Jackknife rating was performed with LABMRMC11) (DBM method: D.D. Dorfman, K Berbaum, University of Iowa, C.E. Metz, University of Chicago) using the continuous certainty
factor method. Rating results according to the

HQ
6.00

ST

4.00
2.00
Threshold Value

0.00
0

20

40

60

80

100

Exposu re Dose [μGy]Fig. 2 Relationship between the root mean square(RMS) and exposure dose using Regius
170.

Arts and Sciences • the original work
Fundamental Study of easy decision method for Optimization of Exposure Dose in Computed radiography.

Vertical(ST)
6μGy
12μGy
23μGy
47μGy
95μGy

1.E-03

1.E-04

1.E-05

1.E-06

1.E-07

1.E-04

1.E-05

1.E-06

1.E-07

0.1

1

10

0.1

1

Spatial Frequency [cycles/㎜]

Spatial Frequency [cycles/㎜]

Horizontal(HQ)

Vertical(HQ)
6μGy
12μGy
23μGy
47μGy
95μGy

1.E-04

1.E-05

1.E-06

Wiener Spectral value [㎜^2]1.E-03

Wiener Spectral value [㎜^2]

6μGy
12μGy
23μGy
47μGy
95μGy

1.E-03

Wiener Spectral value [㎜^2]

Wiener Spectral value [㎜^2]

Horizontal(ST)

1.E-03

10

6μGy
12μGy
23μGy
47μGy
95μGy

1.E-04

1.E-05

1.E-06

1.E-070.1

1.E-070.1

1

10Spatial Frequency [cycles/㎜]

Fig. 3 Result of horizontal Wiener spectrum calculated by two dimension fast Fourieratransform method by Regius 170.
──b(a) standard (ST), (b) high quality (HQ)

using the 2DFFT method. Since the WS values
w ere linearized according to the frequency
bins and each sample was indicated as an average of its 64 SEG, variance in all spatial frequency regions was small and gradual.
Horizontal and vertical WS values for theminimum spatial frequency regions w ere
equivalent. In high-frequency regions, horizontal WS values tended to be slightly lower
owing to the CR property for sharpness to decrease because of the fact that it scans datausing laser light. Moreover, horizontal HQ
spiked when in the vicinity of the Nyquist frequency, possibly owing to the low-pass filter.
The relationship between WS values in the
low-spatial-frequency region (ST: 0.114 cycle/
mm, HQ: 0.229 cycles/mm) and imaging dose

1

10

Spatial Frequency [cycles/㎜]

Fig. 4 Result of vertical Wiener spectrum calculated by two dimension fast Fourier transa
form method by Regius 170.
──b(a) standard (ST), (b) high quality (HQ)

is shown in Fig. 5. WS values increased asdose increased, as was seen with RMS values,
but gradual decreases were observed at doses
higher than the criterion dose of 23 µ Gy.
3-3 ROC analysis and AUC

A comparison of ROC curves for samples
imaged at the criterion dose of 23 µ Gy using
the S/F system SRO250/SRG and the CR ST
and HQ is shown in Fig. 6. Our rating of thestatistically significant difference between thesystems using the paired t-test on both sides
and the Jackknife method indicated that there
were no significant differences. No significant
differences were observed for any of the variance items in the Jackknife analysis-of-variance table for ST and HQ images of CR (Table
Arts and Sciences ◆ 57

Wiener Spectral ｖalue[㎜ ^2]

1).

WS(ST)

1.E-04In the analysis-of-variance table, the degreeof freedom used to calculate the F-distribution
ratio was derived by calculating (c - 1) and (r- 1). The asterisk (*) indicates corrections
made to the degree of freedom by using theSatterthwaite approximation for denominatorsynthesis.

1.E-04
1.E-04at 0.114
cycle/㎜

8.E-05
6.E-05
4.E-05Threshold Value

2.E-050.E+00
0

20

40

60

80

100

Exposure Dose [μGy]df (2) =( MSTR + MSTC + MSTRC ) 2
MS 2 TR MS 2 TC
MS 2 TCR++(r ! 1) (c ! 1) (r ! 1)(c ! 1)

(7)

In this formula, MSTR is the modality-observer variance component, MSTC is the observer-sample variance component, MSTRC is themodality-observer-sample variance component, C is the number of samples, and r is thenumber of observers. The double asterisk (**)
indicates that rating was not performed forobserver-sample (RC) when the sample dispersion was large.

Fig. 5 Relationship between the Wiener spectrum
and exposure dose using Regius 170.
a──(a) standard (ST), (b) high quality (HQ)b

ROC Curves of Film and ST,HQ
T r u e P o s it iv e Fr a c t io n

1.0
0.8
0.6
AUC (0.888) = Film

0.4
AUC (0.890) = ST

0.2

AUC (0.899) = HQ

0.0
0.0

0.2

0.4

0.6

0.8

1.0

False Positive Fraction
Fig. 6 Comparison of ROC analysis by screenfilm systems and computed radiography
for the same dose.

58 ◆ Journal of JART English edition 2015

4. Discussion
The present study investigated the relationship between imaging dose and noise characteristics as well as a simple method for determining imaging conditions for optimal CR imaging dose.
Noise characteristics were indicated by RMS
and WS measurements. Aoki et al12) integrated
WS (u) in the spatial frequency region andcalculated RMS granularity from its squareroot. They reported that their comparison ofthis RMS granularity with graininess assessedusing the paired comparison method indicated that there was good correlation at relatively
low spatial frequency regions around the spatial frequency of 1.0 cycle/mm. The BRH report8) indicated that since there was good correspondence to visual assessments, granularity
characteristics in the S/F system are indicatedby WS values at 0.1 cycle/mm.
RMS values calculated for standard dose DICOM images using Image J were 3.31 for ST

Arts and Sciences • the original work
Fundamental Study of easy decision method for Optimization of Exposure Dose in Computed radiography.

Table 1 Statistically significant (SIG) testing of AUC value using the Two tailed paired t-test and Jackknife
method for Screen-Film system and computed radiography in standard dose.
Jackknife method
Combination(Modality)

Film and ST

Film and HQ

ST and HQ

Source
TOT
T
C
R
TC
TR
RC
TRC
TOT
T
C
R
TC
TR
RC
TRC
TOT
T
C
R
TC
TR
RC
TRC

SourceSums
of
Squares228.0506
0.064620.4241.434521.7887
1.271597.140785.9267241.1264
0.014622.4566
1.118522.57421.293194.2005
99.4689228.3223
0.017821.05270.889721.7308
0.527394.2972
89.8068

Degree offreedom
1439
1
119
5
119
5
595
595
1439
1
119
5
119
5
595
595
1439
1
119
5
119
5
595
595

paired t-test

Mean
Squares

F Ratios

0.06460.1716
0.28690.18310.25430.16330.14441.0513
1.7573
1.26791.76090.01460.18870.22370.18970.25860.15830.1672

1.192
1.41291.13471.547

0.09840.21760.17530.17330.57810.01780.17690.17790.18260.10550.15850.15090.09741.1163
1.12271.20990.69880.75560.20750.347
0.08070.62450.4450

＊

＊＊
＊

＊＊

＊＊

Prob

Decisionp valueSIG.

0.2774＊0.35
0.11970.04050.1189
＊＊
＊

＊＊

＊＊

Film with SRO250/SRG Systemand 3.79 for HQ. We calculated the area ofthe vertical WS (u) spatial frequency region, in
which sharpness is not affected by laser scanning, using the trapezoidal rule and the Simpsonʼs rule. The RMS granularity obtained by
the square root of that value were similar forboth methods, at 3.24 for ST and 3.62 for HQ.
We believe this was due to the fact that no integral error occurred in either method since
the WS (u) spectral variation was small. RMS
values obtained when WS (u) was integrated
were slightly lower. We assume this difference
was due to the fact that the WS (u) integration
range was limited. Thus, in the present study,
RMS and WS can both be used to evaluatenoise characteristics.
RMS values and WS values for ST and HQ
improved as imaging dose increased (Fig. 2,5). We believe this was due to improvements
in granularity caused by the fact that quantum
mottle is in inverse proportion to imaging
dose, which led to improved noise. However,

we observed gradual decreases (improvement)at doses higher than the criterion dose of 23 µ
Gy. We believe that this was due to the factthat while quantum noise is predominant in
the low dose range, system noise becomes
more prominent in the high dose range as thedose increases.
It has been previously pointed out that DR
imaging doses are higher in comparison to S/
F system imaging doses2). Ogawa et al13). compared WS values in the standard S/F system
and CR using an indirect FPD that calculated
overall WS. Their results indicated that sincedoses with the same WS value as the S/F system are 1.3 to 1.5 fold in CR and 1.3 fold in
FPD, in actual clinical practice, they are set atapproximately 1.3 fold the CR and FPD imaging conditions in the S/F system. This result isin accordance w ith the ICRP report 2) thatpoints out the increased exposure used in DR
imaging. However, since doses that are thesame as those used in the S/F system are estiArts and Sciences ◆ 59

mated7) to be in the region in which system
noise is predominant, we believe they play norole in the improved detection ability of visualassessment.
In general, DR imaging is performed under
the same imaging conditions as the S/F system. In the present study, when the dose obtained at a density of 1.0 ± 0.05 in the S/F system was used as the BRH radiation quality
standard, the imaging dose was approximately
23 µ Gy. At this dose, the results of ROC analysis of S/F system and hard copy (film) images of ST and HQ of CR made using the signalsof ⏀ 2.0 mm acrylic beads indicated that the
AUC for detection ability resembled a curvewhen at nearly the same value, that there wasno statistically significant difference in rating,and that standard S/F system images and CR
images were equivalent (Fig. 6, Table 1).
The authors determined that the threshold7)that does not contribute to improvement inimage quality even when the exposure is increased was at the border between the highdose region in which system noise is predominant and the low dose region in which quantum noise is predominant, and that the optimum imaging dose is this threshold value thattakes into consideration a balance between
dose and image quality. The AUC for ST and
HQ hard copy images that w as performed
concurrently showed no statistically significant
differences with the S/F system standard doses
even at 1/2 dose. When one considers that
this 50% value is near the border of detectability, it is possible to consider that the 30%
lower threshold estimated using IQF is the imaging dose that can be efficiently judged as
the balance between noise characteristics andimage quality, which are dependent upon thedose. As a result, unlike previous physical assessment reports, detectability in visual assessments also indicates that the dose can be reduced by 30% lower than the S/F system imaging dose that was set to be the standard.
In the present study, we determined from60 ◆ Journal of JART English edition 2015

the relationship between the RMS and WS values to the imaging dose that the point of intersection in linear approximation of the low
exposure region that is influenced by quantum mottle and the high exposure region thatis dependent upon system noise was 17 µ Gy.
By defining this point of intersection as thethreshold value of the optimization of imaging
dose, we calculated 26% from 17 (µ Gy)/23 (µGy), which was nearly the same result as the
30% we calculated using IQF7). Consequently,
the threshold estimated from RMS and WS values and imaging dose can reduce imaging
dose by 30%, which suggests that it can beused as a parameter for the optimization ofimaging dose.
IQF and AUC signal data obtained using
Burger phantoms and acrylic beads were in alow spatial frequency region8, 10) with a highdegree of correlation with visual characteristics due to the phantom diameter. DQE (u),which is used to assess digital systems, is notaffected by contrast and spatial frequency
characteristics because it is determined by theratio of fluctuation between the average num—
ber of X-ray photons (n) absorbed per unit
area when using CR and FPD devices and thenumber of incident photons (q: dose). Thus,
we were able to logically verify that the CR
X-ray imaging conditions based on film output(hard copy) standards can allow the radiationdose to be lowered to around 70% of the imaging conditions used in the S/F system byusing the threshold that is estimated from RMS
values, WS values for the low spatial frequency region, and imaging dose.
Our investigation of the relationship between noise characteristics and imaging dosein CR and our measurements of RMS and WS
noise allowed us to simply create samples andperform analysis and estimate imaging dosewith equal capacity, in comparison to IQF and
AUC that are visual assessment methods. The
fact that we were able to simply calculate RMS
values using the free image processing soft-

Arts and Sciences • the original work
Fundamental Study of easy decision method for Optimization of Exposure Dose in Computed radiography.

ware Image J is a particular advantage of ourReferences

method. In the future, we would like to investigate the usefulness of optimizing imaging
dose via our method using human equivalentphantoms and establish that our method is a
simple way of determining clinically practical
X-ray imaging dose conditions that is in accordance with the Medical Exposure Guidelines 2006 14) that are recommended by thisjournal.

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rating analysis:Generalization to the population ofreaders and patients with the Jackknife method. Invest Radiol, 27, 723-731, 1992.
12）Yuji Aoki, et al: Zoukanshi no Ryūjōsei. Kyokko X-ray,
No27, 2-29, 1989 (Japanese)
13）Kenichi Ogawa, et al: Evalution of Image Quality andAppropriate X-ray Exposure of a Flat Panel Detector Jpn. J. Radiol. Technol, 57 (5), 587-592, 2001.
(Japanese)
14）The Japan Association of Radiorodical Technologists: Hōshasenryō tekiseika no tame no Iryo hibaku
gaidorain, Bunkodo, 2009. (Japanese)

5. Conclusions
Since systematic and appropriate exposure
guidelines for DR imaging have not yet been
established, it is difficult to set the proper imaging conditions. In the present study, w eused CR to investigate the optimization of
X-ray imaging performed using WS values andimaging dose, w hich w re w ell matched tovisual assessments. Our results suggested thatin these fundamental experiments CR imaging
dose can be lowered to about 70% of the radiation dose based on the ratio bet ween thestandard imaging dose in the S/F system andthe WS value of CR. We also obtained a similar result from the relationship between RMS
value and imaging dose. Noise measurements
using RMS and WS were easier to test andanalyze than the visual assessment method of
IQF and AUC, which indicates that our method is useful as a systematic method of determining X-ray imaging conditions for digital
images.

Arts and Sciences ◆ 61

Arts and Sciencesmaterial

Actual Conditions of Intervention by Radiological Technologists in the Form of Querying
Doubtful Points in Examining Request Slipsfrom Physicians and Dentists
Yasuo Nakazawa1）5） Masaru Nitta2） Chikara Noda3）
Junya Nakashima4） Hisaya Sato1）3） Kyoichi Kato1）4）1）Showa University Graduate School of Nursing and Rehabilitation Sciences2）Department of Radiology, Showa University Northern Yokohama Hospital3）Department of Radiology, Showa University Hospital4）Department of Radiology, Showa University Fujigaoka Hospital5）Department of Radiology, Showa University

Key words: Examination of request slips, querying activities, role of radiological technologists, ensuring medical safe-ty, ensuring the efficacy of examinations and treatment【Abstract】

We conducted a national survey of the actual conditions of intervention by radiological technologists to examine
request slips from physicians and dentists and query doubtful points as a safety measure in radiological examinations
and treatment. As a result, it was found that radiological technologists do perform the activities of examining request
slips from physicians and dentists to query points that are unclear or in doubt in many facilities. At the same time,
it was learned that these activities are not reviewed or recorded as queries. On the other hand, it was clearly shownthat since the role that radiological technologists play by querying doubtful points can prevent the wrong examination
or treatment from being performed or administered, this intervention contributes to ensuring medical safety and theefficacy of examinations and therapy. These results were suggested that queries by radiological technologists arenecessary and important activities from the standpoint of ensuring medical safety.

Introduction
On January 11, 1999, a medical accident occurred in a university hospital, in which a patient scheduled to undergo a heart surgery
was mixed up with another patient scheduled
to undergo a lung surgery. The mistake was
not noticed until the patients were transferredto the intensive care unit (ICU) after the surgeries, which subsequently led to a serious
social problem1) 2). Owing to this medical accident, a paternalistic social community of medical care gradually transformed into patient-centered team medicine, in which patients are considered as partners 3). Subsequently, in the Medical Safety Measure Con-62 ◆ Journal of JART English edition 2015

ference conducted in April 2002, the Ministryof Health, Labor and Welfare prescribed“Comprehensive Measures for the Promotionof Medical Safety,” and requested all hospitals
and clinics with beds to have clear safety
management guidelines, in-hospital systems toreport accidents and other such events, a safety management committee, and implement
staff training for safety management4). These
guidelines required all parties concerned, including the government, to make aggressive
efforts to enhance the safety and reliability of
medical care, because medical safety measures had not been important issues in medical
policy.
Moreover, in order to secure medical safetyArts and Sciences • material
Actual Conditions of Intervention by Radiological Technologists in the Form of Querying Doubtful Points in Examining Request Slips from Physicians and Dentists

and provide anxiety-free and safe medicalcare, an institution was constituted in October
2004 to ensure that national and university
hospitals that offer advanced treatment report
medical accidents5). Such incidents are to bereported to the Center for Medical Accident
Prevention, Japan Council for Quality HealthCare. The council currently has 1,373 medical
facilities as members (March 2014). As a neutral third party organization, the Center for
Medical Accident Prevention assembles the information related to medical accidents andother such incidents, and presents the tabulation/analysis results as a report. This report isavailable to all stakeholders in the society, including medical facilities, citizens, and administrative organizations, to promote information
sharing. In addition, the Ministry of Health,
Labor and Welfare has enforced the revised
Medical Service Law since April 2007, making
it mandatory to have a medical safety management system, drug safety management system, management system for prevention of infections, and medical equipment safety management system.
Although the condition of medical safety
has developed as discussed above, the actual
condition of examination of requests for radiologic examination/therapy by physicians/
dentists working in hospitals and clinics, inradiological technologistsʼ service, and clarification of doubts related to the same, is unclear. Therefore, as a first step in this direction, we conducted a nationwide questionnaire survey of hospitals/clinics on querying
doubtful points by radiological technologists
regarding the radiologic examination/therapy
requests issued by physicians/dentists. Thiswas done by examining “Factual Survey of
Utilization of Medication History and Actual
Conditions of Prescription Queries 6)” reportpublished by the Japan Pharmaceutical Association, Prescription Queries of Pharmacists7),
and Prescription Queries Q&A for Patients8).

1. Methods
1-1. Definition of terms

No studies have been conducted on the actual condition of examination of request slips
or clarification of doubts related to the same,with reference to radiological technologistsʼ
services, since the establishment of the Act on
Medical Radiology Technicians in 1951. Therefore, to help the participating radiological
technologists answer the items in the questionnaire by ensuring a common understanding of the terms, we defined “request slip”,“ examination of a request slip ” , “ querying
doubtful points”, and “change/addition/deletion of examination/treatment” by referring to
the “Factual Survey of Utilization of Medication History and Actual Conditions of Prescription Queries6)”, Prescription Queries of Pharmacists7), and Prescription Queries Q&A for
Patients8) reports.
A “request slip” refers to a slip in which specific instructions have been provided by aphysician or dentist, regarding the exposureof the human body to radiation (regardless ofwhether it is on paper or in an electronicform).
A “Examination of a request slip” refers to
the confirmation by a radiological technologist
as to whether a request slip prepared by aphysician or dentist to conduct imaging examination or radiation therapy (examination/
treatment hereinafter) is appropriate regarding
the following items (excluding the examination of the purpose of examination/treatment):
the side, method, range, position, equipment/
auxiliary tools, interactions, duplication, frequency (too many/too less), burden on human body(radiation exposure/labor), contrast
medium, drug allergy, adverse drug reactions,pregnant/lactating women, etc. With reference
to interactions, the purpose of the examination is to collect information on doubtful
points that may arise due to the interaction in
the same examination/treatment, as well as
Arts and Sciences ◆ 63

between the examination and other examination/treatment, food and drink, etc., querying
doubtful points arising from the examination
order of upper gastrointestinal radiologic examination and abdominal plain radiography,
interference between thyroid gland examination and examination using iodine contrast
medium in the nuclear scanning, and foodand drink before examination.
A “querying doubtful points” refers to theasking for clarification of the “doubtful point,”
if any, in a request slip prepared by the radiological technologist, addressed to the physician/dentist who prepared the original request
slip.
A “ Change/addition/deletion of examination/treatment” refers to change, addition, ordeletion of the instruction details as a result of
the clarification of a “doubtful point” by a radiological technologist, through inquiry withthe physician/dentist, after examination of arequest slip (irrespective of who made thechange, addition, and deletion).
1-2. Survey method
In total, 1,129 facilities participated in thisnationwide questionnaire survey, including
hospitals/clinics selected randomly. The survey period was from December 1, 2012 toFebruary 14, 2013. The self-administeredquestionnaire was mailed to the participants,
and completed questionnaires were received
by mail.
1-3. Details of the questionnaire
The questionnaire comprised three parts.
Part 1 included definition of the terms, Part 2
included items related to general points regarding the hospital, and Part 3 was the factual survey on the examination and querying of
doubtful points on request slips. The major
contents have been presented below:
1) Status of the examination and querying of
doubtful points on request slips.
2) Status of statistical collection, review, andrecording of the examination and querying
doubtful points on request slips.

64 ◆ Journal of JART English edition 20153) Trends in querying doubtful points.
4) Whether near-miss events are reported as
medical safety cases.
5) Detailed contributions of the radiological
technologist through querying doubtful
points.
1-4. Ethical considerations
Before implementation of this questionnaire
survey, the Graduate School of Nursing andRehabilitation Sciences adjudged that the survey would require no approval by the ethics
review board. The institutional data obtained
from this questionnaire were used only in thissurvey. In addition, the identity of the facilities
has been protected while expressing the results.

2. Results
2-1. Response rate

In all, 647 facilities responded, including 81
governmental facilities (governed by the Ministry of Health, Labor and Welfare, National
Hospital Organization, Japan Labor Healthand Welfare Organization, etc.), 137 public facilities (prefectures, municipalities, a part ofpartnerships, etc.), 72 communal facilities(e.g., Japan Red Cross, Social Welfare Organization Saiseikai Imperial Gift Foundation,
Hokkaido Shakaijigyo, Kouseiren, etc.), 22 social insurance-associated groups (e.g., All Japan Federation of Social Insurance Associations, Employeesʼ Pension Welfare Corporation, Shipmen ʼ s Social Insurance Society,
Health Insurance Societies, etc.), 275 medical
corporations, and 60 other facilities. The overall response rate was 57.3%. In terms of thenumber of radiological technologists belonging to those facilities, we found that most of
the facilities, specifically, 358 facilities had 1
to 9 technologists, followed by 130 facilities
that had 10 to 19 technologists, and 74 facilities had 20 to 29 technologists.

Arts and Sciences • material
Actual Conditions of Intervention by Radiological Technologists in the Form of Querying Doubtful Points in Examining Request Slips from Physicians and Dentists

2-2. Response to questions

2-2-2. Status of statistical collection, review,

2-2-1. Status of examinations and querying ofand recording of examinations and que-doubtful points on request slips

rying of doubtful points on request slips

The answers “Radiological technologists examine request slips and query points that are
unclear or in doubt”, “Radiological technologists neither examine request slips nor query
points that are unclear or in doubt”, and “Radiological technologists do not examine request slips” accounted for 85.5% (550 facilities), 5.1% (33 facilities), and 4.4% of the responses, respectively (Fig. 1). The category“Others” included responses such as, “the radiological technologist performs examinations/querying of doubtful points only when related
to general radiography”, “we have no clear
system”, “these are only performed personallyand no efforts are made by our organization”,
and “the receptionist in charge of reservation
performs the prescription queries”.

d. 7（1.1%）
c. 28（4.4%）
b. 15（2.3%）

e. 33（5.1%）

f. 10（1.6%）

The answers “the radiological technologist
examines request slips and the review and record statistics of prescription queries by considering any doubtful points” and “the radiological technologist does not perform this” accounted for 5.4% (31 facilities) and 94.6% (539
facilities) of the responses, respectively (Fig.
2). Querying doubtful points were 963 queries

yes: 31（5.4%）

no:539（94.6%）

Fig.2 Do radiological technologists survey andrecord statistics on queries made regarding“doubtful points” discovered by radiological
technologists who have examined request
slips?
Valid response: 570 facilities (50.5%)（institutions）

a. 550（85.5%）

30
25
20

Fig.1 Do radiological technologists examine
request slips and query points that are
unclear or in doubt?
Valid response: 643 facilities (57.0%)

15

a. Radiological technologists examine request slips andquery points that are unclear or in doubt.
b. Radiological technologists examine request slips but
do not query points that are unclear or in doubt.
c. Radiological technologists do not examine request
slips.
d. Radiological technologists do not query points that are
unclear or in doubt.
e. Radiological technologists neither examine request
slips nor query points that are unclear or in doubt.
f. Other0

10
5
1 - 5051 - 100 101 - 150 151 - 200 201 - 250 251 - 300 301 - 350 351 - 400（cases）

Fig.3 Number of queries made on doubtful points
per month.
* Pertains to the 31 facilities that survey andrecord statistics
Valid response: 31 facilities
Total number of queries: 963 (queries/month)
Mean value: 31.1 (queries/month)
Median value: 10 (queries/month)

Arts and Sciences ◆ 65

Table 1 Number of cases per month in which the instructions are changed, added, or eliminated as a result of
queries.
* Pertains to the 31 facilities that survey and record statistics
Total
number ofqueriesContent of change, addition, elimination[1] Side examined/treated (left/right/upper/lower/both, etc.)[2] Method of examination/treatment[3] Site of examination/treatment[4] Scope of examination/treatment[5] Position of examination/treatment[6] Examination/treatment devices and tools[7] Examination/treatment interactions[8] Redundancy of examination/treatment[9] Number of examinations/treatments (too many/too few)
[10] Burden of examinations/treatments (vocalization, respiration, weighting, position, drugs, other)[11] Contrast medium[12] From drug allergies[13] From adverse effect or suspicion thereof.
[14] Pregnant/nursing women[15] Others (safety confirmation in MRI, violation of rule, patient ID)（institutions）

Percentage
(%)

257
26
90
18
54
38
12
14
9

44.9
4.5
15.7
3.1
9.4
6.6
2.1
2.4
1.6

3

0.5

28
2
14
2
6

4.9
0.3
2.4
0.3
1.0

573

（institutions）

80

90

70

80

60

70
60

50

50

40

40

30

30

20

20

10
0

Number ofqueries

10
0-9

10-19

20-29

30-39

40-49

50-59
（cases）

0

0-19

20-39

40-59

60-79

80-99

100-119（cases）

Fig. 4 Hypothetical effect as if this had been performed as before the change.
(a) Number of queries where an assumption has(b) Number of queries where an assumption has
been made that the patient ʼs physician/been made that the result intended by thephysician or dentist was not obtained.
dentist might damage his/her health.
Valid response: 96 facilities

Valid response: 89 facilities

Total number of queries: 651 (queries/month)
Mean value: 6.8 (queries/month)
Median value: 3 (queries/month)

Total number of queries: 543 (queries/month)
Mean value: 6.1 (queries/month)
Median value: 2.3 (queries/month)

per month in the 31 facilities. An average was31.1 queries per facilities (Fig. 3). The numberof queries in which the instructions werechanged, added, or deleted as a result of prescription queries was the highest for the examination/treatment side (44.9%, 257 queries),
followed by 15.7% (90 queries) for the examination/treatment site, and 9.4% (54 queries)
for examination/treatment position (Table 1).
The monthly number of queries in which ahealth hazard for the patient (exposure to unnecessary radiation, unnecessary drug administration, etc.) was speculated to have occurred if the examination/treatment was conducted according to the instruction before thechange was 651 in 96 facilities, with an average of about 6.8 queries per facilities (Fig. 4a).
In addition, the monthly number of queries inwhich it was speculated that the physicianʼs/dentistʼs intended result would not have been

66 ◆ Journal of JART English edition 2015

Arts and Sciences • material
Actual Conditions of Intervention by Radiological Technologists in the Form of Querying Doubtful Points in Examining Request Slips from Physicians and Dentists

obtained was 543 in 89 facilities, with an average of about 6.1 queries per facilities (Fig.
4b).
2-2-3. Inclination to query doubtful points
Analysis of the trends leading to a query of
doubtful points revealed that most participants
responded “prescription queries tend to go to
specific persons among those who issue request slips”, 246 facilities, followed by “prescription queries tend to go to specific departments”, 222 facilities (Fig. 5). The category“Others” included responses such as “there are
more prescription queries when physicians request for something that is not their specialty”,“copy and paste is frequently used due to theelectronic medical record system”, “the request
slips are illegible”, and “conversation with thepatient leads to a query of doubtful points insome queries”.
2-2-4. Whether near-miss events are reported
as medical safety issues“Near-miss events are reported as medical
safety issues, to an appropriate institutional
section” accounted for 80.2% (465 facilities) of
the responses, whereas “ not reported ” accounted for 19.8% (115 facilities) (Fig. 6).
2-2-5. Detailed contributions of radiological
technologists through prescription queries
When looking at the contributions of radio-

logical technologists through prescription queries, the response “I successfully prevented awrong examination/treatment” was most often
cited (536 facilities), followed by “I successfully ensured safety” (403 facilities), and “I successfully secured efficacy of the examination/
treatment” (377 facilities) (Fig. 7). The category “ Others ” included responses such as “ I
could contribute to construction of a confidential relationship with patients and otherprofessionals such as physicians and nurses”,“I could develop trust in the hospital/medical
facilities”, “a radiogram interpretation helps effective radiography”, “safety of medical practices has improved”, “I could reduce a senseno:115（19.8%）

yes:465（80.2%）

Fig. 6 Are “near misses” and other cases involving
medical safety issues reported to theappropriate department of the facility?
Valid response: 580 facilities (51.4%)（institutions）（institutions）

050

a. The more request slips there
are, the more queries are
made.

100

150

246

d. There is a relationship to howbusy the person who issued
the request slip is.

N o p a r t i c u l a r t re n d s a reobserved.

100

200

a. It was possible to ensure
safety.

148
21c. It was possible to improve
patientʼs QOL.

400

500

600

377

129

d. It was possible to preventt h e w ro n g e x a m i n a t i o nor treatment from being
performed or administered.
e. It was possible to curtail
medical expenses.

300

403

b. It was possible to ensure
the efficacy of examinations
and treatments.

222

c. T h e r e i s a b i a s t o w a r d
specific issuers of request
slips.

f.

250

154

b. T h e r e i s a b i a s t o w a r d
specific departments.

e. There is a bias dependingon the timing of request slip
issuance.

200

0

536

127

138

Fig. 5 Inclination to query doubtful points.
Valid response: 647 facilities (57.3%) (multiple choices allowed)

Fig. 7 Contribution made by the intervention ofradiological technologists who query
doubtful points.
Valid response: 647 facilities (57.3%)(multiple choices allowed)
Arts and Sciences ◆ 67

of uneasiness in the patients”, and “I could
perform the required examination without delay”.

3. Discussion
3-1. Querying doubtful points as an examination procedureRadiological technologists perform absolute
medical practices, as prescribed in the Medical
Practitionersʼ Act. The Article 17 states, “Onemay not perform medical practices unless being a medical practitioner.” Therefore, the request slips received from physicians/dentists,
for radiologic examination/treatment, should
be confirmed as an absolute examination procedure. Such procedures in other medical
professions include prescription queries bypharmacists. The Pharmacists Law, Article 24
stipulates, “When there is any doubtful point
in a prescription, pharmacist may not prepare
a medicine with this unless he/she confirms
the doubtful point by inquiring with the physician, dentist, or veterinarian who has delivered the prescription”. If absolute confirmation procedures by radiological technologists
can be legally stipulated as in the Pharmacists
Law, opinions such as “the radiological technologist performs examinations/prescription
queries only when related to general radiography”, “we have no clear system”, “these are
only performed personally and no efforts are
made by our organization”, “the receptionist in
charge of reservation performs prescription
queries” found in this questionnaire survey
may be improved. We also consider that it caneliminate radiation exposure by unnecessary
radiography that occurs due to absence of
querying doubtful points.
3-2. Status of examinations and querying
doubtful points on request slips
In 85.5% of the facilities that provided valid
responses, radiological technologists performed examinations and querying doubtful
points on request slips. However, it was re-

68 ◆ Journal of JART English edition 2015

vealed that 94.6% of the facilities do not review and record them as querying doubtful
points. In addition, judging from the fact thatexaminations/querying doubtful points aredone only for general radiography, and opinions such as “there is no clear system,” facilities in which the radiology department makes
efforts in examinations and querying doubtful
points on request slips systematically may bevery few in number. However, given the factthat 80.2% of the facilities report querying
doubtful points as near-miss events to the appropriate institutional section, specialized sections such as medical safety office may be engaged in the recording/analysis. Radiological
technologists perform absolute medical practices prescribed in the Medical Practitionersʼ
Act, Article 17 as “One may not perform medical practices unless being medical practitioner”. Therefore, the querying doubtful points
procedure needs to be transformed into a routine procedure as a part of medical safety operations in radiology departments. In addition,
a medical safety office supervising the facilities and radiation department should ensure
implementation of the querying doubtful
points procedure.
3-3. Status of statistical collection, review, andrecording of examinations and querying
doubtful points on request slips
The monthly number of querying doubtful
points in the 31 facilities that reviewed andrecorded the querying doubtful points were
963 queries. Among them, the instructions
were changed, added, or deleted in 573 queries (59.5%), indicating that physicians/dentists
considered that their request contents needed
to be changed in response to the querying
doubtful points raised by radiological technologists. This not only indicates the usefulnessof querying doubtful points, but is also likely
to contribute to promotion of team medicine
practiced with mutual understanding withphysicians/dentists, and sharing of patient information, as well as to improve the quality ofArts and Sciences • material
Actual Conditions of Intervention by Radiological Technologists in the Form of Querying Doubtful Points in Examining Request Slips from Physicians and Dentists

medical safety. Regarding the breakdown ofprescription queries, the side of examination/
treatment (left/right/upper/lower/both) wasmost frequently queried (257 queries/month).
It is acceptable to interpret that these are formal querying doubtful points, such as inquiryof imperfect writing. Although such ambiguities may not arise if the requesting physician/dentist is careful, querying doubtful points byradiological technologists are likely to help
prevention of medical accidents. On the other
hand, it is acceptable to interpret that querying doubtful points for method, site, range,
position, interactions, contrast medium, drug
reaction or its possibility, etc., include elements requiring expertise of imaging and therapeutic radiology. Regarding the influence inthe case of practicing examination/treatment
according to the instruction before change, inother words, queries in which no querying
doubtful points is raised, was observed in 651
queries/96 facilities. The number of queries inwhich it was speculated that a health hazard
would have occurred for the patients or thatthe physician ʼ s/dentist ʼ s intended results
would not have been obtained was found in
543 queries/89 facilities. This indicates thatpractice of querying doubtful points is likely
to bring about a very high advantage to patients and medical facilities.
3-4. Trends in querying doubtful points
Regarding the trend leading to querying
doubtful points, queries tended to go to specific persons among those who issued request
slips, and specific departments. As for specificphysicians/dentists, a likely cause is that nosystematic medical safety education is implemented. However, it is necessary to constructa system in which even the specific physicians/dentists are unlikely to make errors. For
that purpose, the errors made by the specificphysicians/dentists need to be analyzed in detail. As for the specific departments, we consider that the cause may be the busyness ofthe outpatient/inpatient services and requests

for examination based on specificity of thedepartments (erroneous writing of left/right/
upper/lower/both, etc., erroneous writing of
examination site). We consider that careshould be taken to prevent erroneous writingof left and right/upper and lower (the lettersin both pairs look alike in the Chinese character). It is necessary to construct a system inwhich these letters are expressed in Katakana,like “ hidari/migi/ue/shita” instead of using
Chinese characters for “left/right/upper/lower,” as well as to avoid writing alongside thehidari and migi examination sites in the slip.
3-5. Detailed contributions of radiological
technologists through prescription queries
When looking at contributions of radiological technologists through querying doubtful
points, it was found that querying doubtful
points led to prevention of wrong examinations/treatments, security of safety, and security of efficacy of examinations/treatments.
Therefore, the querying doubtful points procedure for radiologic examination/treatment
by radiological technologists are likely to bean effective means to improve quality of medical safety. In addition, responses such as “I
could contribute to building a confidential relationship with patients and other professionals such as physicians and nurses, ” and “ I
could develop trust in the hospital/medical facilities” were frequently answered as othercontributions, which are likely to lead to construction of a confidential relationship as team
medicine and mutual understanding/confidence with medical professionals.

4. Conclusion
This factual survey revealed that radiological
technologists performed examinations andquerying doubtful points on request slips inmany facilities. However, it was also foundthat this operation is not reviewed and recorded as prescription queries. On the other hand,Arts and Sciences ◆ 69

Arts and Sciences • material
Actual Conditions of Intervention by Radiological Technologists in the Form of Querying Doubtful Points in Examining Request Slips from Physicians and Dentists

with regard to the role of radiological technologists through prescription queries, it wasclarified that radiological technologists contribute to ensuring medical safety as well as
efficacy of examinations/treatments, because
consequently wrong examinations/treatments
are prevented successfully. From the above,
querying doubtful points by radiological technologists are indicated to be a required andimportant operation in ensuring medical safety.

Acknowledgments
We appreciate the help of those in facilities
nationwide who cooperated in the questionnaire survey for the present study. We also
thank all of those at the Department of Radiological Technology and other faculties in our
Graduate School of Nursing and Rehabilitation
Sciences who cooperated with us.
The abstract of this article was presented atthe 29 th Japan Conference on RadiologicalTechnologists (in Shimane) in September
2013.

70 ◆ Journal of JART English edition 2015

References:
1) Medical Risk Management Office, Tokyo Marine &Nichido Medical Service Co., Ltd.: My Book of Medical
Safety: Making You Self-confident! 15–16, JapaneseNursing Association Publishing Company, 2013.
2) Ministry of Health and Welfare: Conference Report on
Prevention of Accidents by Misidentification of Patients, 1999.
http://www1.mhlw.go.jp/houdou/1105/h0512-2_10.
html#sanko4
3) Tadashi Sunayashiki, Hiromi Yoshikawa, Tamayo Okamoto, Chikako Koyama: Ethics Textbook for Medical/
Health Professionals, 22–37, Iryo Kagaku-Sha, 2007.
4) Ministry of Health, Labor and Welfare: Comprehensive
Measures for Promotion of Medical Safety, 2002.
http://www.mhlw.go.jp/topics/2001/0110/tp1030-1z.
html5) Ministry of Health, Labor and Welfare: Medical Accident Reporting System, 2004.
http://www.mhlw.go.jp/topics/bukyoku/isei/i-anzen/2/
kaisei0409/
6) Japan Pharmaceutical Association: Factual Survey of
Utilization of Medication History and Actual Conditionsof Prescription Queries 2010, 2010. http://www.nichiyaku.or.jp/action/pr/2011/10/111027_1.pdf
7) Minoru Urushibata: Prescription Queries of Pharmacists, 10–41, Elsevier Japan, 2004.
8) Michiko Hori, Atsuko Kunishige: Querying doubtful
points Q&A for Patients, 7–21, Jiho, 2009.

Contribution

Activities of medical radiologists at a central disaster base hospital following a major earthquake
Toshiki Tateishi
Radiology Department, Sendai Medical Center, National Hospital Organization (independent administrative institution)【Abstract】

We experienced the Great East Japan Earthquake on Friday, March 11, 2011. After the disaster, our workplace, theNational Hospital Organizationʼs Sendai Medical Center, served as a disaster base hospital and a secondary medical
institution to treat those affected by the nuclear power disaster. This article reports on the activities of medical
radiologists at a disaster base hospital in an area struck by multiple major disasters. Our experiences led us to consider
the importance of disaster prevention training, reflect on how institutions should cooperate with each other tocomplete their radiology duties, and suggest ways of providing support to the affected communities.

1. Introduction
On March 11, 2011, a magnitude 9.0 earthquake—the largest ever recorded in Japan—
occurred off the Sanriku Coast. This one natural disaster caused multiple major disasters,
including another earthquake, a tsunami, anda nuclear accident. Three prefectures of the
Tohoku region—Iwate, Miyagi, and Fukushima — were the hardest hit. Medical care inthese prefectures had to be administered withno prospect of lifelines being restored. Additionally, this earthquake disaster caused major
damage to power-generation facilities. All ofJapan experienced power shortages, so scheduled blackouts were conducted throughout
the Kanto region. This placed restrictions on
medical care and led to a variety of problems.
The author ʼ s workplace, Sendai Medical
Center of the National Hospital Organization,is one of 15 hospitals that form a network ofadvanced comprehensive medical care centered around the National Center for Global
Health and Medicine, which is part of the Japanese Ministry of Health, Labour and Welfareʼs
medical policy network. It is centrally locatedin the city of Sendai, which is about 2 km
northeast of JR Sendai Station. This center

consists of 26 medical departments and 698
beds. The hospital addresses several areas ofpolicy medicine, including cancer, heart disease, cerebrovascular disorders, pediatric andparental medicine, designated (intractable)diseases, AIDS, and emergency medicine. It
serves as a central disaster base hospital for
14 institutions in Miyagi Prefecture. After theearthquake, our hospital contributed greatly
to the disaster medical care efforts by offering
our facilities to the Disaster Medical AssistanceTeams (DMATs) 1) so that they could complete
their relief activities.
The Miyagi prefectural government has highdisaster awareness due to its experiences withpast earthquakes off the Sanriku Coast, and it
conducts large-scale disaster drills. Moreover,
the activities of the Miyagi Association of Radiological Technologists include consultations
on radiation exposure and lecture courses.
Various activities have been organized in response to this earthquake disaster, as well.
For more information on the content of these
activities, please visit the associationʼs website(http://www.radtech-miyagi.or.jp/).
While a variety of general articles about theearthquake disaster has been published injournals and elsewhere, few reports take theContribution ◆ 71

perspective of the disaster victims. Such reports are sometimes seen as merely presenting academic data, which can be offensive to
people from areas affected by the disaster. In
addition, although radiologists performed
emergency radiation surveys, their activities
were unfortunately not given much mass media attention.
Here, we report on the activities of medical
radiologists at Sendai Medical Center, a disaster base hospital, during the Great East Japan
Earthquake. The account is slightly chronologically jumbled, but please refer to the attachedfigures.

2. Damage to the Hospital
At about 2:46 p.m. on Friday, March 11,
2011, Sendaiʼs Miyagino Ward was hit by anearthquake with an intensity of 6-upper on
the Japanese seismic scale. The hospital lost
electricity and switched to emergency powersources. We obtained only a very small
amount of information about the extent of thesustained damage from the disaster response
headquarters. Later, we learned that Sendai
Thermal Power Station, operated by Tohoku
Electric Power Co., and other power plants
had come to a halt, causing blackouts over awide area. We began providing medical care,
not knowing what the future would bring. As
for the hospitalʼs lifelines, electricity and gaslines were cut, and while there was still water
available from the city of Sendai, the hospitalʼ
s aboveground and elevated water tanks weredamaged (Fig. 1), and this had a major effecton our care structures in the subsequent days.
Emergency power was supplied using a municipal gas power generation system when the
power got cut off by the earthquake until it
was restored at 11:45 p.m. on Sunday, March
13. The gas supply was also cut off when thedisaster struck, so we subsisted for 4 days onwhat remained in the pipes. If the electricity
coming from the Tohoku Electric Power had

72 ◆ Journal of JART English edition 2015

Lifelines
Electricity

Stopped when the earthquake hit. Restored
at 11:45 p.m. on March 13 (Sunday).

Heating

The part heated by municipal gas was not
functional. The only available means ofheating was hot water circulation using aboiler.

Municipal gas

Remaining gas in the pipes lasted until
March 14, and then we were without it until
March 30.

Water

Major damage to in-house and municipal
water supplies.

Fig. 1. Lifelines after the earthquake

been delayed, it would have placed further
restrictions on the medical care we were able
to provide. It took until March 28 for the municipal gas supply to return to normal.

3. The Hospitalʼs Initial Response
After the earthquake hit, a disaster response
headquarters was established, according to
the hospitalʼs manual, in a third-floor reception room. There were 606 hospitalized patients at the time, but none of the inpatientsnor any staff suffered major injuries. Parts of
the hospital were damaged, but not to the extent that they had to be evacuated. Seven surgeries were being performed at the time thedisaster struck, and all of them were halted
immediately. A triage post was set up at thefront entrance, and a system was implemented with which to accept all cases brought inby emergency transport. Our hospital became
a DMAT gathering base for Miyagi Prefecture,
and at 6:55 p.m. on March 11, the first teamarrived from Yamagata Prefectural Central
Hospital. By 9 p.m. that evening, four teams
had arrived. From that point until the triage
post closed 6 days later, we received support
from 111 teams from around Japan. Medical
radiologists were part of these teams, andthey served to coordinate team operations.
During breaks, these radiologists would visit

Contribution
Activities of medical radiologists at a central disaster base hospital following a major earthquake

the radiology department to offer words ofencouragement and bring snacks. Remembering those times still brings warmth to ourhearts. We received much helpful advice—especially after the explosions at the Fukushima
nuclear plant. Emergency medical care consisted of triage that was performed on 705
people (63 red, 223 yellow, 406 green, 3
black) in the 6 days immediately following thedisaster (March 11-16).

4. The Radiology Departmentʼs
Initial Response
The earthquake knocked things over andcracked some walls in the radiology department, but there was little major damage (Fig.
2). We in the radiology department also responded to the situation according to themanual by surveying the damage in each examination room and recording our observations on checklists, which were then submitted to the disaster response headquarters.
Electricity supplied via emergency power
enabled us to perform simple radiographies inthe emergency imaging room (Fig. 3) and takeimages using a portable device with a charged
battery. CT, MRI, and angiography equipment
was unusable, as it was not hooked up to
emergency power. When the disaster hit, our
hospital was mainly using film. We had

CTCT室
room

CT CT室room

enough stock for about 1 week, but it was uncertain where our next supply would comefrom, so we avoided developing film as muchas possible and made diagnoses based onwhat we saw on the monitors. Although theordering system was usable in some parts of
the hospital, imaging orders were made on
handwritten slips. Patient ID numbers wereassigned based on the device used and ordernumber corresponding to that date. For example, the first CT01 order on March 11 was
numbered CT01031101.
Fig. 4 shows the number of imaging orders
starting from when the earthquake occurred.
Fig. 5 shows the number of people radiographed categorized by time. Power outages
after the earthquake made it impossible tosearch for survivors at night, which is evident
in the smaller number of imaging orders after
7 p.m. on the day of the earthquake. Search
operations resumed during the daylight hoursof the following day and made much progress, leading to an increase in the subsequent number of orders. Fig. 6 shows thenumber of people imaged by body part, andFig. 7 shows the proportions. As the days
passed, the numbers of chest and abdominal
exams outpaced the bone exams. This trend
appears to differ from what occurred after theGreat Hanshin Awaji Earthquake2）.
After the earthquake, the radiology depart-

Emergency
outpatient care
救急外来

Angiography
血管撮影室room

血管撮影室
Angiography
room

Fig. 2. State of damage after the earthquake

Fig. 3. Emergency imaging room during the disaster
Contribution ◆ 73

Number of emergency imaging orders(by day)

Number of emergency imaging orders(by body part)

Imaging room

Chest,
abdominal

19

18
M

ar
ch

17
M

ar
ch

16
M

ar
ch

15
M

ar
ch

14
M

ar
ch

13
M

ar
ch

12

ar
ch

M

ar
ch

M

M

ar
ch

11

Orthopedic

19

18
M

ar
ch

17
M

ar
ch

16
M

ar
ch

15
M

ar
ch

14
M

ar
ch

13
M

ar
ch

12

ar
ch

M

ar
ch

M

M

ar
ch

11

Emergency
imaging roomCT

Fig. 4. Number of imaging orders after the earthquake (by day)Fig. 6. Number of imaging orders after the earthquake (by body part)

Number of emergency imaging orders(by time)

Proportion of body parts that underwent
emergency imaging

Chest,
abdominal

19

18
M

ar
ch

17
M

ar
ch

16
M

ar
ch

15
M

ar
ch

14
M

ar
ch

13
M

ar
ch

12

ar
ch

M

M

ar
ch

11

9 pm

5 pm

9 am

1 pm

1 am

5 am

March 14arch

March 13

9 pm

5 pm

9 am

1 pm

5 am

1 am

9 pm

5 pm

1 pm

9 am

5 am

March 12

M

March 11

1 am

9 pm

1 pm
5 pm

Orthopedic

Fig. 5. Number of imaging orders after the earthquake (by time)

Fig. 7. Number of imaging orders after the earthquake (by body part, proportion)

ment staff confirmed their work assignments.
Then, they returned home in shifts to checkfor damage and ensure their family members
were safe before coming back to the hospital.
Since we anticipated a large number of injured people being brought to the hospital,
we had 3 shifts on the night of the 11th only
and 4 shifts during the day and at night on
the 12th and 13th, and for 3 days. Starting on
the 14th, we employed the same 3-shift duty
system according to which nurses work. After
that, the shift system returned to normal. Mostof the staff worked while cleaning up fromthe disaster, shopping for necessary food-

stuffs, and taking care of other personal matters. Thankfully, many young, single staff
members worked hard, but responding to thedisaster for so long took its toll (Fig. 8). Suchwas the state of things at our hospital, which
has a relatively large staff. At facilities withfewer employees, it must have been much
more difficult.

74 ◆ Journal of JART English edition 2015

Contribution
Activities of medical radiologists at a central disaster base hospital following a major earthquake

Table: Chronological summary of the radiology departmentʼs response to the Great East Japan Earthquake
Date (day)Mar 11 (Fri)

Mar 12 (Sat)Mar 13 (Sun)Mar 14 (Mon)

Mar 15 (Tue)

Time
Content
14:46 ・The Great East Japan Earthquake occurs, causing power outages. The hospital switches
to in-house power sources.
・Response based on Sendai Medical Centerʼs disaster response care manual.
・ Immediately after the earthquake, patient safety is assessed, and evacuations are
performed, if necessary.
15:15 ・Damage to each examination room is surveyed based on a checklist.
15:30 ・Results are reported to the disaster response headquarters in the reception room.
・ Equipment usable on in-house electricity: general imaging device (1 unit) in theemergency imaging room, a portable device (1 unit), and imaging devices in the operating
theater.
16:00 ・Personnel assignments are made based on an anticipated large number of injured people
being brought to the hospital.
11th (Fri) night: 3 shifts
12th (Sat) day and night: 4 shifts
13th (Sun) day and night: 4 shifts
・Necessary items (film, etc.) checked・Radiation exposure records were dealt with using a disaster X-ray exposure record(handwritten).
・Retort pouch food provided by the hospital (beef rice bowl, curry).
8:30 Meeting
・A limited number of devices were re-inspected in order to reduce risk. However, due tothe power outage we could not check whether they were operational.
・Device manufacturers could not be contacted by telephone for an extended period.
・Staff circumstances were surveyed. Many were unable to return home due to damage attheir homes or lack of transportation. Some could not even confirm whether their families
were safe.
・Imaging was performed in the general imaging room using the portable device.
・Support was provided by the radiology department staffʼs family members in the form of
prepared food.
15:36 ・A hydrogen explosion occurs at Reactor No. 1 at the Fukushima Daiichi nuclear power plant.
19:00 ・Now having the nuclear disaster to consider, our response was based on a flowchart
guiding medical care for secondary radiation exposure and early-stage radiation exposurein a nuclear disaster response manual.
・Measurements of atmospheric dose rates begin (indoors and outdoors).
・Retort pouch food provided by the hospital (beef rice bowl, curry).
8:30 Meeting
・Personnel assignments made for the following 3 days.
14th (Mon) day and night: 3 shifts
15th (Tue) day and night: 3 shifts
16th (Wed) day and night: 3 shifts
・Established the agenda for the person in charge of acute radiation exposure screenings.
・Support provided by radiology department staff and their families in the form of preparedfood.
・Some staff had to evacuate their homes with their families due to severed lifelines andtook refuge in the hospital.
23:45 ・100 V power source restored
3:00 ・200 V power source restored
4:30 ・Use of X-ray CT device begins (1 of 2 devices)
8:30 Meeting
・Use of the general device begins
・The staff cafeteria is opened to the public and meal service begins (porridge, etc.). This
continues until April 5.
・Scheduled radiographs are halted, and only emergency exams are performed.
・We prepare to serve as a secondary medical institution for the nuclear power disaster(administrative officials are included in this process).
・Preparation for acute radiation exposure screenings (Tyvek protective gear, etc.)
・Start of acute radiation exposure screenings.
11:01 ・A hydrogen explosion occurs at Reactor No. 3 at the Fukushima Daiichi nuclear power
plant.
6:14 ・Another hydrogen explosion occurs at Reactor No. 2 at the Fukushima Daiichi nuclear
power plant.

Contribution ◆ 75

Mar 16 (Wed)Mar 17 (Thu)Mar 22 (Tue)Mar 24 (Thu)

Apr 14 (Thu)

8:30 Meeting
・Use of the DSA device begins.
・Use of the X-ray television device begins.
・ A lack of film is anticipated, so orders are sent directly to manufacturers, and not
SPD(Supply Processing & Distribution).
・Food is provided (rice balls)
9:00 ・Maximum 11,930.0 ( μ Sv/h) measured at the front gate of the Fukushima Daiichi nuclear
power plant.
9:38 ・Fire breaks out at the No. 4 reactor at the Fukushima Daiichi nuclear power plant.
8:00 ・Vapor is emitted from the No. 3 reactor at the Fukushima Daiichi nuclear power plant.
8:30 Meeting
・Use of an MRI device begins (1 of 3 devices)
・Food is provided (sliced bread)・Personnel assignments are set for the following 5 days.
17th (Thu): regular day shift, 2 staff at night
18th (Fri): regular day shift, 2 staff at night
19th (Sat): regular day shift, 2 staff at night
20th (Sun): regular day shift, 2 staff at night
21st (Mon): regular day shift, 2 staff at night
7:30 ・Soil sampling begins inside the hospital grounds and measurements are made of thesurface contamination density of the parking lot asphalt.
・Whole-body counter measurements begin.
8:30 Meeting・Regular day and night shifts begin this week.
・Certificates are issued in response to requests from individuals who have requested
radiation exposure measurements.
・131I is detected in a sandbox at a nursery school. Play in sandboxes was temporarily
prohibited.
・A supply of radioisotopes is reestablished, and isotope exams begin.
* All devices are usable, starting today.
8:30 Meeting・Miyagi Prefecture (nuclear safety section: 022-211-2606) requests we continue acuteradiation exposure screenings for the time being.
・An individual is assigned the responsibility of ensuring that the acute radiation exposure
screenings are carried out for the next 2 weeks.
16:00 ・The measurement of 131I in nursery school sandboxes goes below the detection limit.

Exhausted staff members

Fig. 8. Exhausted staff members getting some rest

76 ◆ Journal of JART English edition 2015

5. Responding to Acute Radiation
Exposure
Our hospitalʼs acute radiation exposure manual is based on a hypothetical accident occurring at the Onagawa nuclear plant, which isoperated by Tohoku Electric Power, and wetrained and exchanged information with thecompany. Miyagi Prefecture also allocates
funds in its budget to respond to acute radiation exposure. However, this earthquake disaster involved hydrogen explosions at the
Fukushima Daiichi nuclear plant. Our hospital
was active in providing care as a secondary
medical institution for the nuclear disaster. We

Contribution
Activities of medical radiologists at a central disaster base hospital following a major earthquake

Surveys of transported patients

nuclear power-related companies should be
required to budget for and cooperate on themaintenance, regular inspection, and repair ofsurvey meters. The disaster-hit areas have insufficient resources, so it is also necessary tobuild cooperative strategies with neighboring
prefectures.

6. The Importance of Training
Fig. 9. Surveying patients brought by emergency
transportcooperated with the Miyagi prefectural nuclear safety office, and our response was basedon a flowchart showing medical care practices
for secondary and early-stage radiation exposure in a nuclear disaster response manual.
This manual can be found on the website of
the Tohoku branch of the National Hospital
Organization of Radiological Technologists(http://www.nhort.jp/tohoku/saigai/manu.
html) (in Japanese).
In addition, we took environmental measurements. From March 13 to May 8, we performed surface contamination screenings on
141 people and measured internal radiation
exposure in 36 people (Fig. 9). However, as
described above, earthquake damage to thehospitalʼs water tanks prevented us from using
water freely. Fortunately, no patients required
decontamination. During this time, we wereunable to contact other radiation research facilities, so we tried to work with other medical institutions in the prefecture. In the future,some kind of national contact mechanism
should be created. Furthermore, we offered toaid in the process of performing surveys were
made, despite the lack of staff in the areas hit
by the disaster.
We believe there is an urgent need for policies that govern responses to nuclear power
accidents. Moreover, the administration andOur hospital performed regular training involving the entire facility, as well as administrative institutions, on disaster medical careand response to acute radiation exposure. Our
disaster response was immediate because it
occurred during the daytime shift. When I wastransferred to this hospital five years ago, I
was surprised at both the quality and amountof training conducted, which even involved
actual helicopters. This training proved very
helpful in preparing me to face this disaster.
Other institutions no doubt have conductedtrainings and prepared manuals, but it is important that all staff members be informed ofthese endeavors. Employing risk-reduction
methods and troubleshooting is also a valuable disaster-readiness strategy. Furthermore,manuals should be available in both electronic and paper format, and they should be
stored in several separate areas. When a disaster hits, it might not be possible to gain access to some manuals (Fig. 10).

7. Issues in Disaster Medicine
When a disaster strikes a large area, medical
institutions in affected areas where lifelines
have been cut may not be fully prepared toprovide medical care for large numbers of severely injured patients. In these situations, it
may be necessary to transport patients outside
the affected area and perform radical treatments. Imaging diagnostics performed as partof primary surveys based on the Japan Advanced Trauma Evaluation and Care guideContribution ◆ 77

Preparing for adisaster

Not in a condition to
search for a manual !

Yomiuri Shimbun newspaper
article from June 5, 2012

Fig. 10. Factors of concern at the time of a disaster. It may be impossible to access amanual after a disaster.

lines require a portable device for chest andpelvic radiographs. Medical institutions in disaster areas should have the necessary equipment to enable them to perform such surveys.
In this earthquake disaster, however, since it
took a long time to bring the patients experiencing hemorrhagic shock from distant areas
to the hospital, we acutely felt the importanceof having operational CT and angiographyequipment. If power sources will allow, it
would be best to have at least one CT or angiography device available that can run on
emergency power.
As for communication networks, telephones
and email were almost completely non-functional, so communication between disasterbase hospitals was conducted using MCA
wireless networks. The earthquake severely
damaged the landline and network infrastructure. Networks fell as communications structures were destroyed and fuel and batteries
for in-house power generation were exhausted. Medical institutions had enough staff after
this earthquake hit because it occurred during
regular working hours. If it had struck outside
regular working hours, obtaining sufficient
staff would have been a major problem. Thus,
developing an adequate contact system is an
issue that needs to be addressed.
In addition, not only radiology equipment

78 ◆ Journal of JART English edition 2015

but many other types of medical devices need
to be inspected before they are utilized. In
less populated areas, it might also be difficult
to secure repair personnel. In this earthquake
disaster, it was difficult for our hospital to secure repair personnel, even though we are located in Sendai where many companies havesupport centers. Nevertheless, many corporate
vendors we had longstanding working relationships with provided aid. This showed us
how vital personal connections are, and it underscored the importance of considering every
available support system when choosing
which devices to obtain and use in less-populated areas.
Securing power sources has become an important issue since most equipment has been
digitized in recent years. When scheduled
blackouts were announced after the earthquake, medical institutions rushed to reduce
electricity usage and secure power through inhouse generation. Staff should understandroughly how much power a single device requires and how much power would be required to operate a minimum system. It is essential to ensure that systems can run on only
the electricity supplied from in-house power
generation.
After the earthquake, we experienced problems such as supply delays due to a lack ofresources and to repair personnel who wereunable to come because of lack of fuel. A
June 5, 2012, article in The Yomiuri Shimbun
newspaper that was part of a series on hospitals described problems with insufficient inventory, even at disaster base hospitals(Fig. 10). We had enough stock for 3 days,
but after this earthquake it took about a week
until a certain amount of necessary supplies
could be reestablished. Hospitals of our size
should probably stock enough excess material
to last about 1 week.
Moreover, the most important thing to remember in disaster situations that last for extended periods is that the staff members areContribution
Activities of medical radiologists at a central disaster base hospital following a major earthquake

also disaster victims. The people of Tohoku
are known for their stoicism and rarely complained. Still, the longer the people were
faced with the severe damage and the longer
they had to protect their families, the more
psychologically taxing it became. Care efforts
should also be focused on these individuals.
I have heard that associations of physicians,
pharmacists, nurses, laboratory technicians,
and others established personnel and support
systems after the Great Hanshin Awaji Earthquake. The Japan Association of RadiologicalTechnologists and the National Hospital Organization should take the lead in organizing
such initiatives within our community.

ation of person-to-person networks is also important so that help can be provided in timesof trouble. We should also consider the best
course of action for medical radiologists totake during such disasters and how to best
support their efforts.

9. Acknowledgments
We are sincerely grateful to everyone whooffered monetary or material donations orwords of comfort after the Great East Japan
Earthquake. Although my home was half destroyed, which made me a disaster victim, I
am grateful for the opportunities given to me
by my director and editors.

8. In Conclusion
Unanticipated problems arise whenever natural disasters hit. Nonetheless, disaster response training during normal times is essential to minimize the detrimental effects ofthese unexpected disasters. Moreover, the cre-

References
1) What is DMAT? http://www.dmat.jp/DMAT.html
2) Southern Hyogo Prefecture Earthquake Record, Magnitude 7.2 earthquake at 5:46 a.m. on January 17,
1995 – So that our experiences can be made use of in
the future.

Contribution ◆ 79

Journal of JART–English edition 2015–

February 20, 2015
Issuer: Yasuo Nakazawa
Publisher: The Japan Association of Radiological Technologists
31F World Trade Center Building. 2-4-1,
Hamamatsu-cho, Minato-ku, Tokyo. 105-6131
TEL: +81-3-5405-3612 FAX: +81-3-5405-3613
http://www.jart.jp
・Published by The Japan Association of Radiological Technologists.
Ⓒ2015, Printed in Japan.

The Japan Association of Radiological Technologists
http://www.jart.jp