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Alrehily FA, Alqahtani KS, Aljohani MH, Alharbi NS, Alharbi RM, Abdulaal OM, Alshamrani AF, Alsaedi AS, Al-Murshedi SH, Alhazmi FH. Establishing local diagnostic reference levels for computed tomography examinations using size-specific dose estimates. Saudi Med J 2023; 44:761-766. [PMID: 37582572 PMCID: PMC10425620 DOI: 10.15537/smj.2023.44.8.20230230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Accepted: 07/11/2023] [Indexed: 08/17/2023] Open
Abstract
OBJECTIVES To establish local DRL (LDRL) for computed tomography (CT) examinations based on size-specific dose estimates (SSDEs), which consider patient size. The concept of diagnostic reference level (DRL) was introduced to limit patient exposure to unnecessary radiation. However, traditional DRL values do not consider patient size. METHODS Following institutional committee approval, data were collected from CT examinations of adult patients at Madinah General Hospital, Al Madinah Al Munawwarah, Saudi Arabia from January to March 2023. The SSDE was calculated for each patient using the effective diameter (Deff). RESULTS The LDRLs of the brain, cervical spine, chest, thoracic spine and kidneys, ureters, and bladder (KUB) examinations were 118 mGy, 12 mGy, 8 mGy, 17 mGy, and 7 mGy, respectively. A strong correlation was observed between SSDEs and the volume computed tomography dose index (CTDIvol) for all examinations except chest scans (p<0.05). Size-specific dose estimates were higher than the CTDIvol, with a greater difference for patients with smaller Deff (p<0.05). CONCLUSION The established LDRL was within the international DRL. The use of SSDE has the potential to provide more accurate and relevant data for radiation safety practices; however, widespread adoption of SSDE in new CT scanners is necessary for promoting consistency and standardization methodologies.
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Affiliation(s)
- Faisal A. Alrehily
- From the Department of Diagnostic Radiology Technology (Alrehily, Alqahtani, Aljohani, Alharbi, Abdulaal, Alshamrani, Alhazmi), College of Applied Medical Sciences, Taibah University; from the Department of Radiology (Alharbi), King Salman bin Abdulaziz Medical City; from the Department of Nuclear Medicine (Alsaedi), King Fahad General Hospital (Alsaedi), Al Madinah Al Munawwarah, Kingdom of Saudi Arabia; from the Department of Radiological Techniques (Al-Murshedi,), AL-Zahraa University for Women, College of Health and Medical Technology, Karbala; and from Physics Department (Al-Murshedi), College of Education for Pure Sciences, University of Babylon, Iraq.
| | - Khalid S. Alqahtani
- From the Department of Diagnostic Radiology Technology (Alrehily, Alqahtani, Aljohani, Alharbi, Abdulaal, Alshamrani, Alhazmi), College of Applied Medical Sciences, Taibah University; from the Department of Radiology (Alharbi), King Salman bin Abdulaziz Medical City; from the Department of Nuclear Medicine (Alsaedi), King Fahad General Hospital (Alsaedi), Al Madinah Al Munawwarah, Kingdom of Saudi Arabia; from the Department of Radiological Techniques (Al-Murshedi,), AL-Zahraa University for Women, College of Health and Medical Technology, Karbala; and from Physics Department (Al-Murshedi), College of Education for Pure Sciences, University of Babylon, Iraq.
| | - Marwan H. Aljohani
- From the Department of Diagnostic Radiology Technology (Alrehily, Alqahtani, Aljohani, Alharbi, Abdulaal, Alshamrani, Alhazmi), College of Applied Medical Sciences, Taibah University; from the Department of Radiology (Alharbi), King Salman bin Abdulaziz Medical City; from the Department of Nuclear Medicine (Alsaedi), King Fahad General Hospital (Alsaedi), Al Madinah Al Munawwarah, Kingdom of Saudi Arabia; from the Department of Radiological Techniques (Al-Murshedi,), AL-Zahraa University for Women, College of Health and Medical Technology, Karbala; and from Physics Department (Al-Murshedi), College of Education for Pure Sciences, University of Babylon, Iraq.
| | - Nawaf S. Alharbi
- From the Department of Diagnostic Radiology Technology (Alrehily, Alqahtani, Aljohani, Alharbi, Abdulaal, Alshamrani, Alhazmi), College of Applied Medical Sciences, Taibah University; from the Department of Radiology (Alharbi), King Salman bin Abdulaziz Medical City; from the Department of Nuclear Medicine (Alsaedi), King Fahad General Hospital (Alsaedi), Al Madinah Al Munawwarah, Kingdom of Saudi Arabia; from the Department of Radiological Techniques (Al-Murshedi,), AL-Zahraa University for Women, College of Health and Medical Technology, Karbala; and from Physics Department (Al-Murshedi), College of Education for Pure Sciences, University of Babylon, Iraq.
| | - Reyan M. Alharbi
- From the Department of Diagnostic Radiology Technology (Alrehily, Alqahtani, Aljohani, Alharbi, Abdulaal, Alshamrani, Alhazmi), College of Applied Medical Sciences, Taibah University; from the Department of Radiology (Alharbi), King Salman bin Abdulaziz Medical City; from the Department of Nuclear Medicine (Alsaedi), King Fahad General Hospital (Alsaedi), Al Madinah Al Munawwarah, Kingdom of Saudi Arabia; from the Department of Radiological Techniques (Al-Murshedi,), AL-Zahraa University for Women, College of Health and Medical Technology, Karbala; and from Physics Department (Al-Murshedi), College of Education for Pure Sciences, University of Babylon, Iraq.
| | - Osamah M. Abdulaal
- From the Department of Diagnostic Radiology Technology (Alrehily, Alqahtani, Aljohani, Alharbi, Abdulaal, Alshamrani, Alhazmi), College of Applied Medical Sciences, Taibah University; from the Department of Radiology (Alharbi), King Salman bin Abdulaziz Medical City; from the Department of Nuclear Medicine (Alsaedi), King Fahad General Hospital (Alsaedi), Al Madinah Al Munawwarah, Kingdom of Saudi Arabia; from the Department of Radiological Techniques (Al-Murshedi,), AL-Zahraa University for Women, College of Health and Medical Technology, Karbala; and from Physics Department (Al-Murshedi), College of Education for Pure Sciences, University of Babylon, Iraq.
| | - Abdullah F. Alshamrani
- From the Department of Diagnostic Radiology Technology (Alrehily, Alqahtani, Aljohani, Alharbi, Abdulaal, Alshamrani, Alhazmi), College of Applied Medical Sciences, Taibah University; from the Department of Radiology (Alharbi), King Salman bin Abdulaziz Medical City; from the Department of Nuclear Medicine (Alsaedi), King Fahad General Hospital (Alsaedi), Al Madinah Al Munawwarah, Kingdom of Saudi Arabia; from the Department of Radiological Techniques (Al-Murshedi,), AL-Zahraa University for Women, College of Health and Medical Technology, Karbala; and from Physics Department (Al-Murshedi), College of Education for Pure Sciences, University of Babylon, Iraq.
| | - Abdulrahman S. Alsaedi
- From the Department of Diagnostic Radiology Technology (Alrehily, Alqahtani, Aljohani, Alharbi, Abdulaal, Alshamrani, Alhazmi), College of Applied Medical Sciences, Taibah University; from the Department of Radiology (Alharbi), King Salman bin Abdulaziz Medical City; from the Department of Nuclear Medicine (Alsaedi), King Fahad General Hospital (Alsaedi), Al Madinah Al Munawwarah, Kingdom of Saudi Arabia; from the Department of Radiological Techniques (Al-Murshedi,), AL-Zahraa University for Women, College of Health and Medical Technology, Karbala; and from Physics Department (Al-Murshedi), College of Education for Pure Sciences, University of Babylon, Iraq.
| | - Sadeq H. Al-Murshedi
- From the Department of Diagnostic Radiology Technology (Alrehily, Alqahtani, Aljohani, Alharbi, Abdulaal, Alshamrani, Alhazmi), College of Applied Medical Sciences, Taibah University; from the Department of Radiology (Alharbi), King Salman bin Abdulaziz Medical City; from the Department of Nuclear Medicine (Alsaedi), King Fahad General Hospital (Alsaedi), Al Madinah Al Munawwarah, Kingdom of Saudi Arabia; from the Department of Radiological Techniques (Al-Murshedi,), AL-Zahraa University for Women, College of Health and Medical Technology, Karbala; and from Physics Department (Al-Murshedi), College of Education for Pure Sciences, University of Babylon, Iraq.
| | - Fahad H. Alhazmi
- From the Department of Diagnostic Radiology Technology (Alrehily, Alqahtani, Aljohani, Alharbi, Abdulaal, Alshamrani, Alhazmi), College of Applied Medical Sciences, Taibah University; from the Department of Radiology (Alharbi), King Salman bin Abdulaziz Medical City; from the Department of Nuclear Medicine (Alsaedi), King Fahad General Hospital (Alsaedi), Al Madinah Al Munawwarah, Kingdom of Saudi Arabia; from the Department of Radiological Techniques (Al-Murshedi,), AL-Zahraa University for Women, College of Health and Medical Technology, Karbala; and from Physics Department (Al-Murshedi), College of Education for Pure Sciences, University of Babylon, Iraq.
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Sydor M, Majka J, Rychlik M, Turbański W. Application of 3D Scanning Method to Assess Mounting Holes' Shape Instability of Pinewood. Materials (Basel) 2023; 16:2053. [PMID: 36903168 PMCID: PMC10004658 DOI: 10.3390/ma16052053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Revised: 02/23/2023] [Accepted: 02/28/2023] [Indexed: 06/18/2023]
Abstract
Swelling and shrinkage anisotropy affect the susceptibility to an assembly of wooden elements by changing designed clearances or interference fits. This work described the new method to measure mounting holes' moisture-induced shape instability and its verification using three sets of twin samples made of Scots pinewood. Each set of samples contained a pair with different grain patterns. All samples were conditioned under reference conditions (relative air humidity-RH = 60% and temperature 20 °C), and their moisture content (MC) reached equilibrium (10.7 ± 0.1%). On the side of each sample, the seven mounting holes of 12 mm in diameter were drilled. Immediately after drilling, Set 1 was used to measure the effective hole diameter with 15 cylindrical plug-gauges with diameters of 0.05 mm step, while Set 2 and Set 3 were separately re-seasoned by six months in two extreme conditions. Set 2 was conditioned with air at 85% RH (reached an equilibrium MC of 16.6 ± 0.5%), while Set 3 was exposed to air at 35% RH (reached an equilibrium MC of 7.6 ± 0.1%). Results of the plug gauge tests highlighted that holes in the samples subjected to swelling (Set 2) increased an effective diameter in the range of 12.2-12.3 mm (1.7-2.5%), while samples subjected to shrinking (Set 3) reduced the effective diameter to 11.9-11.95 mm (0.8-0.4%). To accurately reproduce the complex shape of the deformation, gypsum casts of holes were made. The 3D optical scanning method was used to read the gypsum casts' shape and dimensions. The 3D surface map of deviations analysis provided more detailed information than the plug-gauge test results. Both the shrinking and swelling of the samples changed the shapes and sizes of the holes, but shrinking reduced the effective diameter of the hole more than swelling increased it. The moisture-induced changes in the shape of holes are complex: the holes ovalized with a different range, depending on the wood grain pattern and hole depth, and were slightly extended in diameter at the bottom. Our study provides a new way to measure 3D hole initial shape changes in wooden elements during desorption and absorption.
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Affiliation(s)
- Maciej Sydor
- Department of Woodworking and Fundamentals of Machine Design, Faculty of Forestry and Wood Technology, Poznań University of Life Sciences, 60-637 Poznań, Poland
- Euroline sp. z o.o., 64-100 Leszno, Poland
| | - Jerzy Majka
- Department of Engineering Mechanics and Thermal Techniques, Faculty of Forestry and Wood Technology, Poznań University of Life Sciences, 60-637 Poznań, Poland
| | - Michał Rychlik
- Institute of Applied Mechanics, Faculty of Mechanical Engineering, Poznan University of Technology, 60-965 Poznań, Poland
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Ohene-Botwe B, Anim-Sampong S, Nkansah J. Development of size-specific dose estimates for common computed tomography examinations: a study in Ghana. J Radiol Prot 2023; 43:011511. [PMID: 36693277 DOI: 10.1088/1361-6498/acb5aa] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 01/24/2023] [Indexed: 06/17/2023]
Abstract
This study determined the size-specific dose estimate (SSDE) of computed tomography (CT) examinations and derived mathematical expressions for dose output estimation and optimization in a teaching hospital in Ghana. Demographic and scanner output indices, including CT dose index (CTDIvol) and dose length product for adult head, chest and abdominopelvic (ABP) CT examinations carried out at the hospital from 2018 to 2020, were retrieved from the picture archiving and communication system of the CT scanner machine. Other indices such as the antero-posterior diameter (DAP), lateral diameter (DL) and diagonal diameter (Ddia) of the patients' bodies were measured on the mid-slice axial image using a digital caliper. The effective diameter (Deff) was then calculated as the square root of the product of theDAPandDL. The SSDEs were calculated as the product of the CTDIvoland the size-specific conversion factors obtained from Report 204 of the American Association of Physicists in Medicine. Regression analyses were performed to find the relationship between SSDE and the various parameters to derive mathematical equations for the dose estimations. There were more female samples (n= 468, 56.3%) than male samples (n= 364, 43.7%) for each CT procedure. The SSDEs and size-specific diagnostic reference levels (SSDRLs) were: head (83.9 mGy; 86.9 mGy), chest (8.1 mGy; 8.7 mGy) and ABP (8.4 mGy; 9.2 mGy). The variations between CTDIvoland SSDEs for head (2.50%), chest (25.9%), and ABP (26.2%) showed an underestimation of radiation dose to patients, especially in chest and ABP examinations, if CTDIvolis used to report patient doses. The SSDEs of the chest and ABP CT examinations showed linear correlations with the CTDIvol. The estimated values could be used to optimize radiation doses in the CT facility. The SSDE and SSDRLs for head, chest and ABP CT examinations have been developed at a teaching hospital in Ghana. The SSDEs of chest and ABP examinations showed linear correlations with the CTDIvoland hence can be calculated using the mathematically derived equations in the study.
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Affiliation(s)
- Benard Ohene-Botwe
- Department of Midwifery and Radiography, School of Health & Psychological Sciences, City, University of London, Northampton Square, London EC1V 0HB, United Kingdom
- Department of Radiography, University of Ghana, Box KB 143, Korle Bu, Accra, Ghana
| | - Samuel Anim-Sampong
- Department of Radiography, University of Ghana, Box KB 143, Korle Bu, Accra, Ghana
| | - Josephine Nkansah
- Department of Radiography, University of Ghana, Box KB 143, Korle Bu, Accra, Ghana
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Amalaraj T, Jeyasugiththan J, Satharasinghe D, Pallewatte AS. Dose reference level based on size-specific dose estimate (SSDE) and feasibility of deriving effective body diameter using tube current and time product (mAs) for adult chest and abdomen computed tomography (CT) procedures. J Radiol Prot 2023; 43:011505. [PMID: 36626827 DOI: 10.1088/1361-6498/acb1bf] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2022] [Accepted: 01/10/2023] [Indexed: 06/17/2023]
Abstract
This study aimed to establish dose reference level (NDRLSSDE) based on size-specific dose estimate (SSDE) derived using effective diameter (Deff) for adult chest and abdomen computed tomography (CT) procedures and to explore the feasibility of drivingDeffusing the product of tube current and time (mAs). In this retrospective study, dose data, scan parameters and patient body dimensions at the mid-slice level from 14 CT units (out of 63 total) were extracted. Additionally, the mAs values of the axial slice at the samez-location where the diameter measurements were made (mAsz) were recorded. Pearson's correlation (r) analysis was used to determine the relationship ofDeffwith patient BMI, weight, and mAsz. The NDRLSSDEfor the chest and abdomen were 9.72 mGy and 13.4 mGy, respectively. The BMI and body weight were less correlated (r= 0.24 andr= 0.33, respectively) withDeff. The correlation between mAszandDeffwas considerably strong (r= 0.78) and can be used to predictDeffaccurately. The absolute dose differences between SSDEs calculated using the AAPM-204 method and mAszwas less than 1.1 mGy (15%). Therefore, mAszis an efficient parameter to deriveDeff. Further, the direct conversion factors to estimate SSDEs at different locations along thez-direction in the scan region from corresponding mAs and CTDIvolwere calculated. The NDRLSSDEsuggested in the present study can be used as a reference for size-dependent dose optimisation in Sri Lanka, and existing NDRL based on CTDIvolunderestimate the average adult CT dose by 36.0% and 39.7% for chest and abdomen regions respectively. The results show that using mAszto determine SSDE is a simple and practical approach with an accuracy of 95% and 85% for abdomen and chest scans, respectively. However, the obtained linear relationship betweenDeffand mAs is highly dependent on the ATCM technique and the user-determined noise levels of the scanning protocol. Finally, the phantom study resulted in the strongest correlation (r= 0.99) between theDwzand mAsz, and the prediction of patient size would be more precise thanDeffmethod.
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Affiliation(s)
- T Amalaraj
- Department of Nuclear Science, University of Colombo, Colombo, Sri Lanka
| | | | | | - A S Pallewatte
- Department of Radiology, National Hospital of Sri Lanka, Colombo, Sri Lanka
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He J, Dong G, Deng Y, He J, Xiu Z, Feng F. Comparison of Application Value of Different Radiation Dose Evaluation Methods in Evaluating Radiation Dose of Adult Thoracic and Abdominal CT Scan. Front Surg 2022; 9:860968. [PMID: 35402481 PMCID: PMC8990916 DOI: 10.3389/fsurg.2022.860968] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 02/22/2022] [Indexed: 11/13/2022] Open
Abstract
Objective To explore the differences among volumetric CT dose index (CTDIvol), body-specific dose assessment (SSDEED) based on effective diameter (ED), and SSDEWED based on water equivalent diameter (WED) in evaluating the radiation dose of adult thoracic and abdominal CT scanning. Methods From January 2021 to October 2021, enhanced chest CT scans of 100 patients and enhanced abdomen CT scans of another 100 patients were collected. According to the body mass index (BMI), they can be divided into groups A and D (BMI < 20 kg/m2), groups B and E (20 kg/m2 ≤ BMI ≤ 24.9 kg/m2), and groups C and F (BMI > 24.9 kg/m2). The CTDIvol, anteroposterior diameter (AP), and the left and rght diameter (LAT) of all the patients were recorded, and the ED, water equivalent diameter (WED), the conversion factor (f size,ED), (f size, WED), SSDEED, and SSDEWED were calculated. The differences were compared between the different groups. Results The AP, LAT, ED, and WED of groups B, E, C, and F were higher than those of groups A and D, and those of groups C and F were higher than those of groups B and E (P < 0.05). The f size,ED and f size, WED of groups B, E, C, and F are lower than those of groups A and D, and those of groups C and F are lower than those of groups B and E (P < 0.05). CTDIvol, SSDEED, and SSDEWED in groups B, E, C, and F are higher than those in groups A and D, and those in groups C and F are higher than those in groups B and E (p < 0.05). In the same group, patients with chest- and abdomen-enhanced have higher SSDEWED and SSDEED than CTDIvol, patients with chest-enhanced CT scans have higher SSDEWED than SSDEED, and patients with abdomen-enhanced CT scans have higher SSDEED than SSDEWED (P < 0.05). Conclusion CTDIvol and ED-based SSDEED underestimated the radiation dose of the subject exposed, where the patient was actually exposed to a greater dose. However, SSDEWED based on WED considers better the difference in patient size and attenuation characteristics, and can more accurately evaluate the radiation dose received by patients of different sizes during the chest and abdomen CT scan.
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Affiliation(s)
- Jimin He
- Department of Radiology, The First People's Hospital of Longquanyi District, Chengdu, China
| | - Guanwei Dong
- Department of Radiology, The First People's Hospital of Longquanyi District, Chengdu, China
| | - Yi Deng
- Department of Rehabilitation, The First People's Hospital of Longquanyi District, Chengdu, China
| | - Jun He
- Department of Radiology, The First People's Hospital of Longquanyi District, Chengdu, China
| | - ZhiGang Xiu
- Department of Radiology, The First People's Hospital of Longquanyi District, Chengdu, China
| | - Fanzi Feng
- Department of Radiology, The First People's Hospital of Longquanyi District, Chengdu, China
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Sookpeng S, Martin CJ, López-González MR. Simplified approach to estimation of organ absorbed doses for patients undergoing abdomen and pelvis CT examination. J Radiol Prot 2021; 41:1288-1303. [PMID: 34488213 DOI: 10.1088/1361-6498/ac241d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 09/06/2021] [Indexed: 06/13/2023]
Abstract
The volumetric computed tomography (CT) dose index (CTDIvol) is the measure of output displayed on CT consoles relating to dose within a standard phantom. This gives a false impression of doses levels within the tissues of smaller patients in Southeast Asia. A size-specific dose estimate (SSDE) can be calculated from the CTDIvolto provide an assessment of doses at specific positions within a scan using size-specific conversion factors. SSDE is derived using the water equivalent diameter (Dw) of the patient, but calculation ofDwrequires sophisticated computer software. This study aimed to evaluate relationships betweenDWand effective diameter (DEff), which can be measured more readily, in order to estimate SSDE at various positions within a routine clinical abdomen and pelvis CT examination for Thai patients. An in-house ImageJ algorithm was developed to measureDw, effective diameter (DEff), and SSDE on CT slices located at the heart, liver, kidneys, colon, and bladder, on 181 CT examinations of abdomen and pelvis. Relationships betweenDEffandDwwere determined, and values of organ absorbed dose usingDEffwere estimated. This approach was validated using a second cohort of 54 patients scanned on a different CT scanner. The results revealed that ratios betweenDEffandDwat the heart level were 1.11-1.13 and those for the others were about 1.00. Additionally, the SSDE/CTDIvolratio was estimated for each organ in terms of exponential functions using the relationships betweenDwandDEfffor individual organs. In summary, this study proposed a simple method for estimation of organ absorbed doses for Southeast Asian patients undergoing abdomen and pelvis CT examinations where sophisticated computer software is not available.
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Affiliation(s)
- S Sookpeng
- Radiological Technology Department, Faculty of Allied Health Sciences, Naresuan University, Muang, Phitsanulok Province, 65000 Thailand
| | - C J Martin
- Department of Clinical Physics and Bioengineering, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - M R López-González
- Department of Clinical Physics and Bioengineering, Institute of Neurosciences and Psychology, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
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