Normal Reference Values in Han Adults of Skin Thickness and Blood Flow by High-frequency Ultrasound: a Multicenter Study in China
Conditions: Healthy Volunteer, Skin
Sponsor: First Hospital of China Medical University

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Normal Reference Values in Han Adults of Skin Thickness
and Blood Flow by High-frequency Ultrasound:
a Multicenter Study in China（NOVAS-HFUS Study）
2023.05.28

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[Research Background]
The skin is the body's largest organ and acts as a protective, permeable
barrier against pathogen invasion and against chemical and physical attacks.
Long-term exposure to solar ultraviolet radiation is a major factor in exogenous
skin aging. With the gradual improvement of living standards and the
development of medical cosmetology technology, Chinese consumers have
gradually increased their acceptance of cosmetology consumption. Facial skin, as
one of the important indicators of "beauty", has obviously received the attention
of cosmetic surgeons and dermatologists. Skin thickness is one of the important
indicators of facial aging. However, different gender, different parts of the skin
thickness is very different, especially the facial skin, the thickness of the
epidermis, dermis is different, and the facial plastic surgery, injection treatment,
photoelectric treatment has a close relationship. In addition, the dermis is rich in
blood vessels, especially in its deep layers, which play an important role in the
nutritional support of tissues and homeostasis of the internal environment. With
the increase of age, the degree of dermal vascularization decreases, which is also
one of the factors affecting skin aging. Therefore, in aesthetic medicine, more
accurate quantitative evaluation of skin thickness and blood flow rather than
simple subjective evaluation is very important.
Ultrasound is a non-invasive imaging technique widely used in clinic. In
recent years, with the development of ultrasound technology, the frequency of
ultrasonic probes has been increasing. Because of its higher resolution,
high-frequency ultrasound can clearly display the layer and structure of the skin,
and achieve accurate measurement of skin thickness and evaluation of dermal
blood flow. High-frequency ultrasound has become a new non-invasive tool for
the diagnosis of skin diseases, aesthetic medicine and preoperative and
postoperative evaluation. The purpose of this multi-center Study is to establish
the normal reference values of skin thickness and blood flow parameters by
high-frequency ultrasound in Chinese Han adults, and to explore the influencing
factors, so as to provide quantitative reference for the evaluation of facial skin
aging degree and cosmetic treatment.

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[Research Objective]
1. To establish the normal values of skin thickness and blood flow parameters of
Chinese Han adults by high-frequency ultrasound;
2. Determine the influencing factors of skin thickness and blood flow
parameters.
[Study Protocol]
1.
Overall process
This is a prospective multicenter clinical study conducted in the People's
Republic of China. The multi-center clinical study method was adopted.
The plan is to start preparatory work, training and other preliminary work in
May 2023, and to start implementation in August 2023, for a period of 18 months.
The first 12 months are the data collection stage, and the last 6 months are the
data analysis and summary stage. Through the sample size calculation, the skin
UHF ultrasound data of 540 healthy Chinese people need to be collected for
analysis and statistics.
Each participating unit shall provide a registered doctor with experience in
ultrasound examination as the person in charge and specific implementer, and
conduct centralized training in advance.
Subjects were screened strictly according to clinical manifestations, blood
pressure and blood biochemistry. According to the Chinese Medical Association
Ultrasound Guidelines for Skin Diseases (2022 edition), images were collected
using a unified standard, and standardized skin thickness and blood flow
parameters were measured.
The participating units shall ensure that the relevant data of the candidates
shall be recorded in the case report form (CRF) in a true, accurate, complete and
timely manner. The CRF is kept by a special person, and the ultrasonic
examination results collected by each unit are uniformly verified and analyzed by
professionals.
Duration of the study process: It is planned to start in August 2023 and last

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for 18 months.
2023.08-2024.7
Data collection phase
2024.08-2024.10
Data analysis phase
2024.11-2025.01
Data summary phase
2.
Experimental equipment
Canon Aplio i900 ultrasonic diagnostic instrument, image acquisition unified
use of PLI-3003BX probe.
3.
Research objects
A total of 540 healthy Han Chinese adults were included, 270 male and 270
female.
3.1 Inclusion criteria:
Each volunteer must meet the following criteria to be included in the study:
(1) Han nationality;
(2) Ages 18-79;
(3) Normal blood pressure (139-90/89-60mmHg);
(4) Body mass index < 30 kg/m2;
(5) Blood routine, fasting blood glucose, blood lipid, liver and kidney
function, electrocardiogram were normal;
(6) No history of skin disease, connective tissue disease, cardiovascular
disease, diabetes, severe liver and kidney dysfunction.
(7) No history of drug use affecting cardiovascular system.
3.2 Exclusion criteria：
(1) Skin diseases (such as eczema, psoriasis, scleroderma, etc.);
(2) Any skin disease at the test site (such as dermatitis, acne, breakages,
previous skin lesions, etc.);
(3) chronic systemic diseases;
(4) Use corticosteroid drugs or immunosuppressants;
(5) Pregnant or lactating women;
(6) People who have been exposed to ultraviolet radiation for a long time or
have a history of sun exposure within 3 months;
(7) The examined skin area has previously received other treatments;

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(8) Unable to cooperate with the ultrasonic examination.
4.
Eligibility of subjects
Subjects are required to meet all inclusion criteria without any exclusion
criteria and sign an informed consent form. In addition, the subjects are required
to provide copies of blood routine, liver function, kidney function, blood glucose,
blood lipids, electrocardiogram and other reports within the past 3 months.
5.
Confidentiality of subject information
The personal information of all cases will be hidden to ensure the privacy of
the subjects.
[Quality control]
1.
Initial qualification of researchers
(1) All participants should have at least 1 year of relevant ultrasound
experience
and
have
performed
at
least
100
superficial
ultrasound
examinations.
(2) All participating centers are required to have a Canon Aplio i900
ultrasonic diagnostic instrument equipped with a PLI-3003BX probe.
(3) All participating researchers are required to follow the same skin
ultrasound reporting principles, i.e. standard sampling sites and measurement
methods.
2.
Training
(1) Intensive training: mainly includes basic operation, collection position,
quality control methods, influencing factors, and understanding of case report
form (CRF) and reporting tools.
(2) After centralized training, each sub-center should complete:
Standard mode presets: according to the requirements of inspection mode
in centralized training, standardized presets are made for parameters such as
two-dimensional gray scale image, color Doppler image and spectral Doppler
image.
Image acquisition quality control: Complete the collection of 2 cases
according to the standardized collection process, and upload all materials.

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Case collection form quality control: Upload the data information of the
above 2 cases according to the standard CRF form filling and submission process.
The information will be reviewed by PI. If there is any non-compliance with the
regulations, PI will give modification suggestions. Normal image collection can
be carried out only after all materials of the 2 cases meet the qualification
standards.
3.
Quality control standards of member institutions
If the following circumstances occur and are confirmed by PI assessment,
you will automatically withdraw from this study:
The research institution fails to pass the qualification examination;
Researchers who fail to pass the qualification examination; Each research center
must submit more than the specified number of cases per month, if it cannot
provide them on time; The proportion of sample shedding (including unqualified
case images, untrue case data collection, failure to complete and submit forms in
time, etc.) should be controlled within 20%. If the sample drop rate exceeds 20%,
the PI assessment will give a reminder, warning, and withdrawal from the study.
The head of the main research unit and the investigator should perform their
respective duties, strictly follow the clinical study protocol, use standard
operating procedures, and verify all measurement results to ensure the quality
control of clinical studies and the implementation of quality assurance systems.
[Risk pre-assessment and disposal plan]
Pre-risk assessment: Medical ultrasound imaging systems have been
proven to be one of the safest imaging devices and have been used in daily care.
Ultrasonic non-invasive, no ionizing radiation. Therefore, the likelihood that the
subject will be at risk from the ultrasound is almost zero.
Subject safety: According to the purpose of the study, the ultrasonic safety
management in this study followed the ALARA principle (As Low As
Reasonably Achievable, the reasonable use of low dose), that is, the lowest
ultrasonic energy was used on the basis of available effective data. This study did
not use any of the new drugs in the study for intervention.

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Helsinki Declaration: The conduct of this research will be guided by the
ethical principles of medical research involving human subjects, which was
formulated by the Joint General Assembly of the World Medical Associations in
1964 and revised in 1975 (Tokyo), 1983 (Venice), 1989 (Hong Kong), 1996
(West Somerset) and 2000 (Edinburgh).
[Distribution of research results]
1.
The research resources, research results and database generated during
the research process shall be owned by PI unit. For papers and other theoretical
results produced by this research, PI is the corresponding author in principle, the
first author is produced by PI unit, and the person in charge of other sub-centers
is the author of the paper. The journal may limit the number of authors, according
to the order of contribution; If the new addition is selected as a quality control
unit, the ranking will move forward, and the remaining signature order will be
determined according to the contribution of the sub-center to the case data
meeting the requirements.
2.
Papers and theoretical results based on the research results of each
research center shall be shared by each of them. However, if any relevant papers
are published, they should be conducted after the publication of the papers of this
multicenter study. Each research center is encouraged to use the single center data
of its own sub-center to publish papers or submit relevant results.
3.
If each research center needs to use multi-center case data for research, it
needs to apply to PI, and can use it after PI's approval.
4.
The patent formed shall be enjoyed by the applicant, and the income
from the transfer shall be enjoyed by the applicant. The results of applied
research, such as the clinical protocols developed, are shared by all participating
research centers.
5.
When applying for the national incentive results of this research, one PI
unit: the First Affiliated Hospital of China Medical University will be the first
applicant, and the research leader will be the first applicant.
6.
Research centers are encouraged to apply for other levels of awards, and

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are obliged to apply and explain to PI in advance if they need to use the case data
content of multi-center studies.
[Project management scheme]
1.
Researchers and research management structures
Each clinical investigator is responsible for conducting the study in
accordance with protocol, all applicable laws, regulations, and ICH Guidelines
(GCP).
2.
Ethics Committee approval
The PI Unit investigator is responsible for ensuring that all aspects of the
ethics review are conducted in accordance with the current guidelines of the
Commission and/or in accordance with local and regional laws (to the extent that
maximum protection is provided to study subjects). The protocol and any
information provided to subjects to obtain informed consent (including written
ICFs, subject recruitment procedures [such as advertisements] and written
information [such as information leaflets]) must be reviewed and approved by a
qualified EC prior to subject enrollment. Prior to inclusion, the responsible person
must receive the EC's approval of the study/proposal.
Amendments to the protocol and amendments to informed consent must also
be submitted to the EC for approval before they are implemented by the Research
Centre.
The investigator must provide the EC with a progress report at the time
interval required by the EC and re-evaluate and approve the study as required.
Copies of progress reports and study re-approval documents must be sent to the
responsible person.
After the completion or termination of the study, the investigator must
submit a final report to the EC and send a copy of this report to the responsible
person.
3.
Ethics
This study will be conducted using guidelines designed to protect the rights
and well-being of human subjects participating in biomedical research, in

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compliance with all applicable national or local EC audit and informed consent
requirements.
4.
Patient information and informed consent
Informed consent must be obtained before each patient is enrolled in the
study, and the requirements specified in the NHFPC guidelines, health
regulations, and/or local regulations must be complied with (whichever provides
the greatest degree of protection). Written and oral information describing the
nature and duration of the study must be provided to each patient in an
understandable manner. In addition, patients must be given sufficient time to
consider the potential risks and benefits associated with participating in the study.
The informed consent must also contain language that allows the responsible
person (or designated representative), the regulatory authority and the EC to have
direct access to the patient's medical records for review.
Informed consent forms must be signed and dated by the patient. The ICF
must also be signed and dated by the person who obtained the informed consent.
As part of the study documentation, the investigator must retain a signed and
dated ICF and must provide a copy to each subject or their authorized
representative.
Subjects have the right to withdraw from the study at any time during the
study.
5.
Confidentiality of subject information
Affirms and supports the principle that subjects have the right to privacy
protection. During the study period and during all data analysis, all subjects' data
will be identified by subject identification number and initials only.