bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dosimetric comparison between single and double isocenters VMAT for SRT with multiple targets
Authors: Lwin Lwin Kyaw Wai , Suriyapee Sivalee , Jumpangern Chotika , Sanghangthum Taweap 
Published: June 2020

Abstract
The focal irradiation approach for brain metastasis (BMs) Stereotactic Radiosurgery (SRS) or Stereotactic Radiotherapy (SRT) has emerged as an important modality for multiple BMs. This study aimed to evaluate the dosimetric effects between single isocentre (SI) and double isocentres (DI) VMAT SRT of multiple brain metastases. Eighteen VMAT SRT plans with varying lesions size, number and distance were simulated on patient CT image using Eclipse treatment planning system version 15. The plan consists of 3 techniques in: 2 coplanar arcs SI, 1 coplanar combine with 2 non-coplanar arcs SI and 2 non-coplanar and 1 coplanar arc DI. The VMAT plans were generated with 21Gy prescription dose to all lesions in 3 fractions. The plans were evaluated in terms of Gradient index (Paddick GI), Conformity index (Paddick CI), and Homogeneity index (ICRU HI) for PTV and V12Gy and V6Gy for normal brain. The same dose constraints were used to optimize for all cases. On the average result from 3 techniques, 3 arcs SI plans and DI were better in GI (14.79±5.83, 13.70±4.72) and CI (0.63±0.08, 0.62±0.09) than 2 arcs SI (17.56±6.15, 0.62±0.11), while HI values was comparable for all techniques. For normal brain, V12Gy for 2 arcs and 3 arcs SI plans were comparable with DI and the volumes of normal brain receiving 6 Gy in 3 arcs SI and DI (77.40 ± 34.30 cm3, 68.94 ± 30.50 cm3) were better than 2 arcs SI (108.10 ± 57.20 cm3). Moreover, the number of arcs, monitoring units and treatment time were also increased and inconvenience in practice in DI. In conclusion, 3 arcs non-coplanar SI VMAT technique presents the suitable in dosimetric evaluation in 2-5 lesions metastases SRT.
Computer-Aided Diagnosis (CAD) to Detect Brain Abnormality from PET Image using Artificial Neural Network (ANN)
Authors: Kusumawardani Y. , Ratianto  , Prajitno P. , Soejoko D. S. 
Published: June 2020

Abstract
PET imaging is powerful to diagnose the presence of abnormalities, staging cancer, and evaluating radiotherapy treatment results. Sometimes, small uptake is not easily visual recognized, hence an additional supporting method for its detection is needed. In this study, Computer-Aided Diagnosis (CAD) of brain abnormalities from PET images using segmentation and classification methods based on a feature in the form of Gray Level CoOccurrence Matrix (GLCM) was developed Artificial Neural Network (ANN) is used to deal with the classification problems arising in this application. We develop CAD in this study using MATLAB. A total number of samples were 360 images with 180 abnormal (14 patient) and 180 normal (20 patient) images were used as training and testing data. The result based on Receiver Operating Characteristic (ROC) illustrated that the training error was 4.22 ± 2.37 % and the test error was 12.30 ± 3.47%. These results mean that this developed CAD system can recognize normal and abnormal brain images.
Current-Voltage Response of Cold White LED Strip to Radiotherapeutic Electron and Photon Beams: A Preliminary Study
Authors: Damulira E , Yusoff MNS , Omar AF , Taib NHM , Kamal SAM , Dani SM , Abdullah R 
Published: June 2020

Abstract
Photonic devices such as photodiodes, phototransistors, solar cells, and charge-coupled devices (CCDs) have been associated with clinical radiation detection in recent studies. Light Emitting Diodes (LEDs) are of low-cost in comparison to photodiodes and available in various flexible designs, including surface mount devices (SMDs). LEDs are purposely designed to emit light, but they can also be implemented for detecting light in a photovoltaic mode. Despite the LED-related merits, a few studies, compared to other photonic devices, especially photodiodes, have adopted them as medical radiation detectors. This research hence exploits the LED’s dual applicability by investigating a cold/cool white LED strip current-voltage (C-V) signal response to photon and electron beams. Radiation parameters such as beam energy, angle of incidence, field size, surface source distance (SSD), and monitor units (prescribed dose) were varied. According to the obtained results, the electron beams induced a 10% higher C-V signal compared to photon beams. An angular dependence was also observed, i.e., the C-V signal fluctuated due to a variation in the irradiation angles; -45°, -25°, 0°, 25°, 45°, and radiation type – photon and electron beams. The C-V signal response to SSD alterations additionally produced bimodal signal graphs, skewed towards shorter SSDs, for all the beams used in this study. Finally, the C-V signal was generally linear to the prescribed dose for both the photon and electron beams. Overall, the response of LEDs to photon and electron beams separately exhibited a similar signal trend for the beam energy, field size, angular dependence, and SSD parameter variations. On the other hand, dose linearity produced contrasting signal trends across the photon and electron beams.
Stopping power ratio databases for proton therapy dose calculation
Authors: Pischom N , Asavaphatiboon S , Tangboonduangjit P , Liamsuwan T 
Published: June 2020

Abstract
In modern radiation therapy, ion beams are increasingly used for cancer treatment. Protons are light ions that have Bragg peak characteristic in the depth dose distribution that is optimal for minimizing dose to surrounding normal tissues. In proton therapy treatment planning, the stopping power ratio (SPR) of a given medium to that of water is used for calculating the water-equivalent pathlength (WEPL) of tissues in the patient. Since SPR is related to the computed tomography (CT) number, the conversion from CT numbers to SPRs can be used to find WEPLs of tissue voxels, which are sequentially applied in selecting the initial proton energy. In this work, we investigated the effect of using different CT number to SPR conversion models on proton pencil beam dose calculation. In the SPR calculation, either elemental mean excitation energy (I-value) from the ICRU report or elemental mass stopping power from SRIM software were used. For each approach, four energy dependent scenarios were investigated. The ICRU model and the SRIM model showed a monotonic correlation of SPRs for most tissue types. The 2D dose distribution was calculated by a MATLAB-based proton therapy treatment planning system, PSPLAN. The results suggest that elemental I-values and elemental mass stopping power can be used interchangeably for SPR calculation. Moreover, CT number to SPR conversion models obtained for specific proton energy and average proton energy did not cause difference in pencil beam dose calculation unless the proton energy was relatively low.
Beam matching of two linear accelerators, identical model and brand
Authors: Donmoon T , Wattanachaiyasit S , Kaewboonperm U , Meennuch E , Klaitong C 
Published: June 2020

Abstract
The final goal of this work is to interchange ongoing irradiated patients between the two linear accelerators (LINACs), without re-planning if any malfunction of one machine. Having two identical LINACs, only two years apart, it is our opportunity to try using beam matching techniques. First of all, we followed the vender’s criteria, however, these are insufficient to ensure the interchangeability of the patients. The purpose of this work is to describe further and compare measurements and parameters after the initial vendor-recommended beam matching of the two LINACs. After completion of the acceptance test and initial vendor-recommended beam quality test, several parameters were measured to confirm the level of beam matching in both LINACs. The measurement consisted of specific point dose (output factors, head scatter factors, and wedge transmission factors), percentage depth dose, and beam profile. All beam matching parameters from our two LINACs are comparable and acceptable value approximate ±1% or less for both photon and electron beams; therefore, it is possible to interchange accelerators for ongoing irradiated patients without re-planning for dosimetric data as part of the treatment planning system. However, these parameters should be frequently measured/re-checked and compared between LINACs in a part of hospital quality assurance programs. Additional, the safest and most practical way to ensure that two accelerators are within acceptable clinical accuracy is to include treatment planning system (TPS) calculations in the evaluation.
Beam spot position measurement using corotational penumbra modulation and image center shift methods
Authors: Rofikoh  , Rafliansyah A , Sugiyantari  , Soejoko D S 
Published: June 2020

Abstract
Image and treatment quality of radiotherapy are influenced by the position of beam spot, therefore it is important to know the position of the beam spot. Beam spot position measured by the corotational penumbra modulation (CPM) and the image center shift (ICS). The CPM method uses a cylindrical ion chamber that rotate with collimator angle. The position of ion chamber, jaws, central axis are fixed to collimator angle. The signal measured to half blocked field 10x20 cm2 for every 30° collimator angle. The beam spot calculated from signal measurement results. The ICS method uses two radiopaque rings with 8.5 cm diameter. Both of rings are placed at different heights of 64.5 cm and 150 cm SSD. Image acquired by varying both collimator and couch angle for every 30° and the beam spot position calculated by measuring the shift of rings centre. Measurement also performed using ball bearing test. Beam spot shift values from the CAOR using CPM and ICS measurements are closely similar, in the range of 0.05-0.65 mm and 0-0.53 mm respectively. The measurement using CPM and ICS methods can be used for routine quality assurance (QA) to ensure that the beam spot position still in tolerance.
Comparison of Dosimetry Characteristics from Some Bolus Materials for 6 and 10 MV Photons Beam Radiation Therapy
Authors: Sekartaji G , Aisyah S. , Carina C.C.C , Nazara T. , Nainggolan A , Endarko  
Published: June 2020

Abstract
In radiation therapy, bolus material is often used for increased surface dose, compensate for surface irregularities and internal heterogeneities. Bolus has properties equivalent to water and soft tissue. In this study, the mixture of Silicone Rubber (SR) and Bismuth was used for bolus fabrication and then compared to commercial boluses such as Paraffin, Play-Doh, and Paraffin Wax. The study aims to evaluate the comparison of relative electron density (RED), effective mass attenuation coefficient, transmission factor, percentage of surface dose (PSD), and Percentage Depth Dose (PDD) for all boluses. The bolus was made with the size 11 × 11 × 0.5 cm3. Physical density of the synthesized bolus was assessed by computerized tomography (CT) Scanning. The results of the RED analysis for the mixture of Silicone Rubber (SR) and Bismuth, Paraffin, Play-Doh, and Paraffin Wax were 0.954; 0.743; 0.933; and 0.878, respectively. The values of RED for all boluses has a similar to water and soft tissue. These results prove that the bolus is equivalent to soft tissue density such as fat, breast, lungs, and liver. Furthermore, for other dosimetry tests such as transmission factors and attenuation coefficients using Linear Accelerator (LINAC) with photon energy sources 6 and 10 MV. In general, Percentage of surface dose at 6 MV is higher than 10 MV. The highest percentage of the surface dose was achieved by paraffin wax at 6 MV energy by 85%. For effective mass attenuation coefficient result, the highest is the mixture of silicone rubber and bismuth at -0.0030 cm2/g for 6 MV and Play-Doh at -0.0114 cm2/g for 10 MV.
Automated patient position in CT examination using a Kinect camera
Authors: Afrieda Nissa , Anam Choirul , Setia Budi Wahyu , Dougherty Geoff 
Published: June 2020

Abstract
Proper positioning of the patient in the CT examination is important. Patients who are not properly positioned at iso-center can affect the distribution of radiation dose. Every patient is unique, hence matching a center of the patient with the iso-center is not a trivial task. This study has developed a system for automatic patient centering using a Kinect camera located at the right or left side of a patient. A plastic water slab phantom was used for calibrating pixel value and pixel size for various distances. Twenty patients were automatically positioned by the Kinect camera and the results were compared to manually positioning by medical personnel. It was found that the value and size of the pixel depend on the Kinect camera-object distance. The value and size of pixels linearly increase with the increase of distance. The difference between the manual patient positioning by medical personnel and the automatic method by the Kinect camera was 1.80 ± 0.95 cm. The difference for the 6 patients was more than 2 cm, and for the 14 patients was less than 2 cm. Hence, the Kinect camera with automatic software can help in positioning patients automatically and accurately in real-time so that it can reduce time and effort in finding patient centers.
Silicone rubber with lead-acid composite as alternative radiation filter in digital radiography (DR)
Authors: Irdawati Yulia , Sutanto Heri , Anam Choirul , Hidayanto Eko , Zahroh Fatimatuz , Wiratma Jaya Gede , Susanto Bambang 
Published: June 2020

Abstract
Digital Radiography (DR) uses poly-energy x-rays beams, where low-energy x-rays are easily absorbed by the tissues and do not contribute to the image, therefore the low energy x-rays should be removed from the beam. The use of the radiation filter is an effective method for minimizing low-energy. The purpose of the research was to produce an alternative radiation filter for protecting organs and minimizing the dose received by patients while maintaining the quality of the image in DR examination. In this study, the radiation filters were made from Silicone Rubber–Lead Acid (SR-Pb), with the dimension of 17 x 17 x 0.6 cm3. The Pb percentage in the SR-Pb was varied from 0 to 5 wt%. To find out the feasibility of SR-Pb as a radiation filter, the dose reduction was measured using a solid-state detector (the Piranha detector, RTI Electronics, Sweden). For image quality assessment, images of the foot phantom were visually analyzed. The contrast-to-noise ratio (CNR) and signal-to-noise-ratio (SNR) values of the CDR TOR phantom with and without an SR-Pb radiation filter were measured. By the addition of Pb wt%, the foot image is still in the readable range. Analysis from the TOR CDR phantom, provided that there is no significant different between CNR and SNR value with and without SR-Pb radiation filter. The addition of Pb wt% slightly reduced the CNR and increased the SNR. SR-Pb 5 wt% decreased dose down to about 50%. This study has successfully developed the SR-Pb as an alternative radiation filter for the protection in DR examination, especially for indications that do not require an excellent low-contrast image, for example in the bone examination.
Establishment Diagnostic Reference Level for CT-Scan Procedure in Indonesia
Authors: Bagus Gede Putra Pratama Ida , Rusmanto  
Published: June 2020

Abstract
Diagnostic Reference Level (DRL) is an effective tool in an effort to increase optimization. The purpose of this study is to establish Indonesian DRL (IDRL) for CT-Scan modality for adult patients. Data collection was done by collecting data from each hospital through SI-INTAN application. The minimum data that have to be reported was 20 patients per procedure for each hospital. IDRL analysis was carried out if there are at least 20 hospitals participating in the survey for certain procedures. Establishment of IDRL was based on an analysis of 75 percentiles from each hospital DRL, while the hospital DRL was based on the median of patient data. IDRL analysis for CT-Scan was based on CTDIvol and DLP quantity. In addition, an analysis of the scan length of 1-phase procedure was done. The analysis was carried out for some procedures, Head, Chest and Abdopelvis. For CTDIvol, the IDRLs were 65mGy, 14mGy and 17mGy for Head, Chest, and Abdopelvis respectively. For DLP, the IDRLs were 1400 mGy.cm, 759 mGy.cm and 1350 mGy.cm for Head, Chest, and Abdopelvis respectively. Based on scan length analysis, information was obtained that most Head procedures were carried out between 16-25 cm. While the scan length for Chest procedure was 31-50 cm and for Abdopelvis was 41-65 cm. From these results, this study can be used as profile baseline of IDRL for CT-Scan modality in Indonesia. The results indicate that optimization must be done for CT-Scan in Indonesia.
An improvement in automatic MTF measurement in CT images using an edge of the PMMA phantom
Authors: Zabilal Hak Elzami , Anam Choirul , Setia Budi Wahyu , Dougherty Geoff 
Published: June 2020

Abstract
We have developed an improved method of modulation transfer function (MTF) measurement using an edge of the polymethyl methacrylate (PMMA) phantom which is normally positioned for computed tomography dose index (CTDI) measurement. In CTDI measurements, the peripheral holes of the PMMA phantom are set at the 3, 6, 9 and 12 o’clock positions. The upper edge of the phantom image has a hole, which precludes its use in calculating the MTF. To circumvent this, the phantom image was homogenized by replacing all pixel values inside the phantom with the median value of the phantom pixels. Subsequently, we were able to calculate the MTF by measuring the edge spread function (ESF) curve, calculate the line spread function (LSF) curve, and obtain the MTF curve by Fourier transform. The resulting MTF curve using our proposed method was then compared with the tail replacement method which had been proposed previously. Our method is superior to the tail replacement method which results in some inhomogeneity of the ESF curve in the part inside the phantom.
Influence of Various Setup Parameters on Scattered Fraction in Interventional Cardiology
Authors: Ardiatna W. , Pratiwi N. G. , Pawiro S. A. , Wigati K. T. , Soejoko D. S. 
Published: June 2020

Abstract
It is important to examine the positions of the medical staff involved in interventional cardiology in order to minimize their accumulated scattered radiation doses. This study used the design of experiment (DOE) method with three parameters (C-arm gantry tilt, position and height), each at three levels (low, medium and high), on both the left and right sides of the patient, to analyse the interactions between the parameters that influence the scattered fraction in interventional cardiology. In this experiment, a RANDO phantom and an Unfors Xi survey detector were used to measure the rate of the scattered dose exposed to staff without protective shielding in a Cath lab. The parameters that significantly influenced the scattered fraction at a confidence level of 95% (P< 0.05) to the right of the patient were the gantry tilt and the height. To the left of the patient, all parameters significantly influenced the scattered fraction.
Recognizing Intrapulmonary Lymph Node (IPLN) and Lymph Node in Soft Tissue Image from Low Dose Computed Tomography (LDCT) and Standard Dose Computed Tomography (SDCT): Study Using CIRS Phantom
Authors: Saragih Y , Lestariningsih I , Mu’minah I A , Nurlely  , Soejoko D S 
Published: June 2020

Abstract
Low Dose Computed Tomography (LDCT) is well-known for lung screening which administers low dose on the patient. In screening, intrapulmonary lymph node (IPLN) and lymph node in mediastinum (soft tissue) need special attention. In this research, nodule simulations with 36-85 Hounsfield units (HU) were made. IPLN was embedded inside lung simulation medium that was shaped as the module for 002LFC CIRS Thorax Phantom. The same method was also used for lymph node that was embedded in the soft tissue area. Image acquisition was conducted using LDCT and SDCT (Standard Dose Computed Tomography) methods with 100 kV and 120 kV exposure condition. The variations for mAs were 11, 25, 30, and 50 for LDCT and 70, 80, 90, 100 for SDCT. The result showed that IPLN image could be detected using LDCT method at 100 kV. Meanwhile, lymph node in soft tissue was not easily detected using LDCT because the noise in LDCT was relatively higher than in SDCT.
177Lu Effect of Geometry Factors in Radionuclide Calibrator
Authors: Widodo Prasetya , Candra Hermawan , Rahmah Hidayati Nur , Sekar Humani Titis 
Published: June 2020

Abstract
The accuracy of radiopharmaceutical activity which will be administered to the patients is very important in nuclear medicine, especially in the case of therapeutical procedure. Hence, all safety aspects should be considered, including the standardization of the dose calibrator. From the reference, the accuracy of dose calibrator is influenced by various factors, such as the geometrical factors of the syringes or vials. The aim of this work was to investigate the effect of different container such as syringes and vials on the accuracy of dose calibrator. The initial work was done by preparing 5 cc glass ampoule and 1 cc syringes containing 177Lu. Both samples was measured using the Capintec CRC 7-BT dose calibrator. The ampoule and syringe activity was measured at the base of the chamber and 5 cm above the base of the chamber, respectively. The result shows that the correction factor was 2.5 % for the syringe and 1.03 % for the ampoule. The correction factor should be considered when the dose calibrator will be used for measuring the administered to the patient to get more accurate activity measurement and patient safety.
Effectiveness of Post National Dose Survey (NADs1) Towards Dose Compliance Level
Authors: Kayun Z. , Karim M.K.A. , Shaari A.H. , Mahmud R. , Rahmat S.M.S. 
Published: June 2020

Abstract
The increasing number of CT procedures owing to advanced CT technology requires careful monitoring by the personnel involved to ensure appropriate examinations and optimized procedures. For that reason, CT optimization is a crucial factor that could help to compensate for [[[AUTHOR: Could this sentence be clarified with more specific information? For example, you might say that optimization compensates for the poor image quality that can occur with low radiation. Thank you.]]] radiation dose and image quality. In current practice, optimization in CT is a complex procedure due to a wide range of acquisition parameters in imaging protocols. Diagnostic Reference Levels (DRLs) have been defined by the International Commission on Radiation Protection (ICRP) as a form of investigating the level of patient dose for a specified procedure used in medical imaging to indicate whether, in routine conditions, the patient dose is unusually high or low for that procedure. Hence, the Ministry of Health (MOH) has established a national DRL through a dose survey conducted from 2007 to 2009, and the project is called as NADS1. However, the study does not cover the effectiveness of image quality; in contrast, the current research focuses on both dose exposure and image quality to determine the level of effectiveness of the developed NADS1 data. This study involves several levels, including the acquisition of patient exposure data, image quality assessment, and effective dose measurement. Determination of acquisition of patient exposure data is based on the indicator of QAP CT Brain developed by the MOH, i.e., the total number of adult CT brain examinations for which the DLP value shall not exceed 10% of the national DRL values, 1050 mGy.cm. The outcome of this study can be used as a measure to optimize patients’ radiation exposures and can be a guide for implementing improvement measures. The results of this study allow radiology personnel to understand the concepts and mechanisms associated with managing patient radiation exposures. The outcome also provides the level of effectiveness of the developed QAP, which was implemented by the MOH and subsequently became a benchmark for improving the quality of healthcare services. Therefore, it is clear that this study has shown an impact on the level of optimization from the radiation exposure study, the NADS2 that is being implemented.