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Mardfar S, Ghaziyani MF, Mortezazadeh T, Zamani H, Rahimiyan M, Khezerloo D. Radiation doses and diagnostic reference levels for common CT scans in adults in Northwest region of Iran. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2024:10.1007/s00411-024-01074-3. [PMID: 38839606 DOI: 10.1007/s00411-024-01074-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Accepted: 05/20/2024] [Indexed: 06/07/2024]
Abstract
This study aims to estimate organ dose and cancer risks, establish region-specific diagnostic reference levels (DRLs), and determine achievable doses (ADs) for common CT procedures in adults in the northwest of Iran. Effective and organ doses were estimated using VirtualDoseCT software in a sample of 480 adult patients who underwent head, sinus, chest, and abdomen-pelvis (AP) CT scans. The guidelines provided by the BEIR VII report were utilized to estimate cancer risks. Effective and organ doses for specific procedures were determined, with the highest mean organ dose being observed in the brain during head CT examinations, with a value of 54.02 mGy. It was observed that the lungs in chest examinations and the colon in AP examinations had the highest risk of cancer, with rates of 30.72 and 21.37 per 100,000 persons, respectively. Higher cancer risk values were generally exhibited by females compared to males. The DRLs for common CT examinations were established as follows: Head CT (CTDIvol 41 mGy, DLP 760 mGy cm), Sinus CT (CTDIvol 16 mGy, DLP 261 mGy cm), Chest CT (CTDIvol 8 mGy, DLP 287 mGy cm), and AP CT (CTDIvol 9 mGy, DLP 508 mGy cm). Significant variations in dose distribution among facilities were identified, indicating the need for optimization. The study highlights the importance of minimizing radiation exposure to critical organs and promoting patient safety in CT examinations. The establishment of region-specific DRLs and ADs can help optimize radiation doses and reduce cancer risks for patients.
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Affiliation(s)
- Sina Mardfar
- Department of Radiology, Faculty of Allied Medical Sciences, Tabriz University of Medical Science, Tabriz, Iran
| | - Mona Fazel Ghaziyani
- Department of Radiology, Faculty of Allied Medical Sciences, Tabriz University of Medical Science, Tabriz, Iran
| | - Tohid Mortezazadeh
- Department of Medical Physics, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hamed Zamani
- Department of Medical Physics, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Melika Rahimiyan
- Department of Radiology, Faculty of Allied Medical Sciences, Tabriz University of Medical Science, Tabriz, Iran
| | - Davood Khezerloo
- Department of Radiology, Faculty of Allied Medical Sciences, Tabriz University of Medical Science, Tabriz, Iran.
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Simantirakis G, Hourdakis CJ, Kalathaki M, Liotsou V, Nikolaou M, Pafilis C, Thrapsanioti Z, Tritakis P, Carinou E. Updating national diagnostic reference levels for computed tomography in Greece: Challenges on patient protection optimisation. Eur J Radiol 2024; 175:111429. [PMID: 38508091 DOI: 10.1016/j.ejrad.2024.111429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 01/18/2024] [Accepted: 03/13/2024] [Indexed: 03/22/2024]
Abstract
The escalating use of Computed Tomography (CT) imaging necessitates establishment and periodic revision of Diagnostic Reference Levels (DRLs) to ensure patient protection optimization. This paper presents the outcomes of a national survey conducted from 2019 to 2022, focusing on revising DRLs for adult CT examinations. Dosimetric data from 127 scanners in 120 medical facilities, representing 25% of the country's CT scanners, were collected, emphasizing geographic distribution and technology representation. Τhe parameters used for DRLs were the CTDIvol and the DLP of a typical acquisition of the region of interest (scan DLP). In addition to the 7 CT examination for which the DRL values were revised, establishment of DRLs for neck, cervical spine, pelvic bones-hips, coronary artery calcium (Ca) score and cardiac computed tomography angiography (CCTA) examinations was performed. Revised DRLs exhibited a 15 % average decrease in CTDIvol and a 7 % average decrease in scan DLP from the initial DRLs. This reduction of dosimetric values is relatively low compared to other national studies. The findings revealed wide variations in dosimetric values and scan lengths among scanners, emphasizing the need for standardization and optimization. Incorporation of advanced technologies like Iterative Reconstruction (IR) showcased potential for further dose reduction, yet challenges in uniform implementation persist. The study underscores the importance of ongoing optimisation efforts, particularly in the context of increased CT utilization and evolving technology. The revised DRLs have been officially adopted in Greece, emphasizing the commitment to safe and effective CT practices.
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Affiliation(s)
- George Simantirakis
- Greek Atomic Energy Commission, P.O. Box 60092, 153 10, Agia Paraskevi, Athens, Greece.
| | - Costas J Hourdakis
- Greek Atomic Energy Commission, P.O. Box 60092, 153 10, Agia Paraskevi, Athens, Greece
| | - Maria Kalathaki
- Greek Atomic Energy Commission, P.O. Box 60092, 153 10, Agia Paraskevi, Athens, Greece
| | - Vasiliki Liotsou
- Greek Atomic Energy Commission, P.O. Box 60092, 153 10, Agia Paraskevi, Athens, Greece
| | - Magda Nikolaou
- Greek Atomic Energy Commission, P.O. Box 60092, 153 10, Agia Paraskevi, Athens, Greece
| | - Christos Pafilis
- Greek Atomic Energy Commission, P.O. Box 60092, 153 10, Agia Paraskevi, Athens, Greece
| | - Zoi Thrapsanioti
- Greek Atomic Energy Commission, P.O. Box 60092, 153 10, Agia Paraskevi, Athens, Greece
| | - Panagiotis Tritakis
- Greek Atomic Energy Commission, P.O. Box 60092, 153 10, Agia Paraskevi, Athens, Greece
| | - Eleftheria Carinou
- Greek Atomic Energy Commission, P.O. Box 60092, 153 10, Agia Paraskevi, Athens, Greece
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Establishment of national diagnostic dose reference levels (DRLs) for routine computed tomography examinations in Jordan. POLISH JOURNAL OF MEDICAL PHYSICS AND ENGINEERING 2023. [DOI: 10.2478/pjmpe-2023-0003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Abstract
Background: Dose reference levels (DRLs) are used as indicators as well as guidance for dose optimization and to ensure justification of appropriate dose for a given clinical indication. The main aims of this study were to establish local DRLs for each CT imaging protocol as a reference point to evaluate the radiation dose indices and to compare our DRLs with those established in other countries and against the internationally reported guidelines.
Materials and methods: 2000 CT dose reports of different adult imaging protocols from January 2021 until April 2022 were collected retrospectively at different hospitals in Jordan. Data were collected from CT scans that were performed using different types and models of CT scanners and included four adult non-enhanced, helical CT imaging protocols; Head, Chest, Abdomen-Pelvis, and Chest-Abdomen-Pelvis.
Results: The average doses of CTDIvol, DLP, and effective dose were (65.11 mGy, 1232.71 mGy·cm, 2.83 mSv) for the head scan, (16.6 mGy, 586.6 mGy·cm, 8.21 mSv) for the chest scan, (17.91 mGy, 929.9 mGy·cm, 13.9 mSv) for the abdomen-pelvis scan, and (19.3 mGy, 1152 mGy·cm, 17.25 mSv) for the chest-abdomen-pelvis scan. In comparison with results from different international studies, DLP values measured in the present study were lower for the chest-abdomen-pelvis and abdomen-pelvis CT scans, and higher for the head CT and chest CT scans.
Conclusions: It is very important that each country establishes its own DRLs and compares them with those reported by other countries, especially the developed ones. It is also important that these levels are regularly updated.
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Albahiti SK, Barnawi RA, Alsafi K, Khafaji M, Aljondi R, Alghamdi SS, Awan Z, Sulieman A, Jafer M, Tamam N, Tajaldeen A, Mattar EH, Al-Malki KM, Bradley D. Establishment of institutional diagnostic reference levels for 6 adult computed tomography examinations: Results from preliminary data collection. Radiat Phys Chem Oxf Engl 1993 2022. [DOI: 10.1016/j.radphyschem.2022.110477] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Jusoh II, Abdullah KA, Ali MH. DIAGNOSTIC REFERENCE LEVELS FOR COMMON CT EXAMINATIONS: RESULTS FROM A STATEWIDE DOSE SURVEY. RADIATION PROTECTION DOSIMETRY 2022; 198:1417-1423. [PMID: 36093894 DOI: 10.1093/rpd/ncac182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 08/09/2022] [Accepted: 08/17/2022] [Indexed: 06/15/2023]
Abstract
The aim of this study was to investigate the current radiation doses for CT examinations throughout a state in Malaysia and, based on this data, to propose local diagnostic reference levels (DRLs) for the most common CT examinations. A study was conducted in three of the four hospitals that have provided CT services throughout the state. A survey booklet was designed to facilitate collection of pertinent CT scan data. The following information were extracted and recorded for each study: tube voltage, tube current, number of scans phases, CT dose index volume (CTDIvol) and dose length product (DLP). Proposed local DRLs of CT brain and thorax were up to 12% lower than the current national DRLs. However, an increase of DLP (median value) for CT abdomen was also found as compared to the 75th percentile of national DRLs. Therefore, considerable optimisation should be made to achieve a better dose reduction.
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Affiliation(s)
- Irwan Iskandar Jusoh
- School of Medical Imaging, Faculty of Health Sciences, Universiti Sultan Zainal Abidin, Kuala Nerus, Terengganu 21300, Malaysia
| | - Kamarul Amin Abdullah
- School of Medical Imaging, Faculty of Health Sciences, Universiti Sultan Zainal Abidin, Kuala Nerus, Terengganu 21300, Malaysia
| | - Mohd Hanafi Ali
- Discipline of Medical Imaging Science, Sydney School of Health Sciences, Faculty of Medicine and Health, Level 7, University of Sydney, D18 Susan Wakil Health Building, Western Avenue, Camperdown, NSW 2006, Australia
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Papanastasiou E, Protopsaltis A, Finitsis S, Hatzidakis A, Prassopoulos P, Siountas A. Institutional Diagnostic Reference Levels and Peak Skin Doses in selected diagnostic and therapeutic interventional radiology procedures. Phys Med 2021; 89:63-71. [PMID: 34352677 DOI: 10.1016/j.ejmp.2021.07.029] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 07/08/2021] [Accepted: 07/20/2021] [Indexed: 02/06/2023] Open
Abstract
PURPOSE Institutional (local) Diagnostic Reference Levels for Cerebral Angiography (CA), Percutaneous Transhepatic Cholangiography (PTC), Transarterial Chemoembolization (TACE) and Percutaneous Transhepatic Biliary Drainage (PTBD) are reported in this study. MATERIALS AND METHODS Data for air kerma-area product (PKA), air kerma at the patient entrance reference point (Ka,r), fluoroscopy time (FT) and number of images (NI) as well as estimates of Peak Skin Dose (PSD) were collected for 142 patients. Therapeutic procedure complexity was also evaluated, in an attempt to incorporate it into the DRL analysis. RESULTS Local PKA DRL values were 70, 34, 189 and 54 Gy.cm2 for CA, PTC, TACE and PTBD respectively. The corresponding DRL values for Ka,r were 494, 194, 1186 and 400 mGy, for FT they were 9.2, 14.2, 27.5 and 22.9 min, for the NI they were 844, 32, 602 and 13 and for PSD they were 254, 256, 1598 and 540 mGy respectively. PKA for medium complexity PTBD procedures was 2.5 times higher than for simple procedures. For TACE, the corresponding ratio was 1.6. PSD was estimated to be roughly 50% of recorded Ka,r for procedures in the head/neck region and 10% higher than recorded Ka,r for procedures in the body region. In only 5 cases the 2 Gy dose alarm threshold for skin deterministic effects was exceeded. CONCLUSION Procedure complexity can differentiate DRLs in Interventional Radiology procedures. PSD could be deduced with reasonable accuracy from values of Ka,r that are reported in every angiography system.
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Affiliation(s)
- Emmanouil Papanastasiou
- Medical Physics Laboratory, School of Medicine, Aristotle University of Thessaloniki, AHEPA University Hospital, Thessaloniki, Greece.
| | - Athanasios Protopsaltis
- Medical Physics Laboratory, School of Medicine, Aristotle University of Thessaloniki, AHEPA University Hospital, Thessaloniki, Greece
| | - Stefanos Finitsis
- Department of Radiology, School of Medicine, Aristotle University of Thessaloniki, AHEPA University Hospital, Thessaloniki, Greece
| | - Adam Hatzidakis
- Department of Radiology, School of Medicine, Aristotle University of Thessaloniki, AHEPA University Hospital, Thessaloniki, Greece
| | - Panos Prassopoulos
- Department of Radiology, School of Medicine, Aristotle University of Thessaloniki, AHEPA University Hospital, Thessaloniki, Greece
| | - Anastasios Siountas
- Medical Physics Laboratory, School of Medicine, Aristotle University of Thessaloniki, AHEPA University Hospital, Thessaloniki, Greece
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Zewdu M, Kadir E, Tesfaye M, Berhane M. ESTABLISHING LOCAL DIAGNOSTIC REFERENCE LEVELS FOR ROUTINE COMPUTED TOMOGRAPHY EXAMINATIONS IN JIMMA UNIVERSITY MEDICAL CENTER SOUTH WEST ETHIOPIA. RADIATION PROTECTION DOSIMETRY 2021; 193:200-206. [PMID: 33866377 DOI: 10.1093/rpd/ncab028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 11/18/2020] [Accepted: 02/08/2021] [Indexed: 06/12/2023]
Abstract
The main purpose of this study was to determine local diagnostic reference level (LDRL) for Routine Computed Tomography (CT) examination in, Jimma University Medical Center (JUMC) South West Ethiopia. Retrospective study was conducted to determine LDRL for routine CT examination in JUMC. We have considered CTDIvol and DLP as dosimetric quantity based on the recommended guidelines to determine LDRLs by different international legal Authorities. The 75th percentile values of the calculated CTDIvol and DLP were proposed as LDRL. LDRL was obtained as CTDIvol, 42.97mGy, 7.76mGy, 14.32mGy, and 10.86mGy for routine brain CT, routine chest CT, routine thoraco-lumbar CT and routine abdomen CT examination respectively. Similarly the determined LDRL from DLP was 1364.15mGycm, 368.96mGycm, 853.18mGycm, and 1568.96mGycm for brain, chest, thoraco-lumbar and abdomen examination respectively. The LDRL obtained for DLP was higher compared with international DRLs; it can be reduced by coordinating effort between radiologists, technologists and medical physicist.
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Affiliation(s)
- Mesfin Zewdu
- Medical Physicist, Jimma University Radiology Department, PO Box 378, Jimma, Ethiopia
| | - Elias Kadir
- Medical Physicist, Jimma University Radiology Department, PO Box 378, Jimma, Ethiopia
| | - Million Tesfaye
- Medical Physicist, Jimma University Radiology Department, PO Box 378, Jimma, Ethiopia
| | - Melkamu Berhane
- Medical Physicist, Jimma University Radiology Department, PO Box 378, Jimma, Ethiopia
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Khelassi-Toutaoui N, Merad A, Tsapaki V, Meddad F, Sakhri-Brahimi Z, Guedioura D, Saadi S. ADULT CT EXAMINATIONS IN ALGERIA: TOWARDS UPDATING NATIONAL DIAGNOSTIC REFERENCE LEVELS. RADIATION PROTECTION DOSIMETRY 2020; 190:364-371. [PMID: 32885243 DOI: 10.1093/rpd/ncaa116] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 06/24/2020] [Accepted: 08/06/2020] [Indexed: 06/11/2023]
Abstract
A pilot study has concerned the most frequent computed tomography examinations (CT). This represents the first results based on actual survey for diagnostic reference levels (DRLs) establishment in Algeria. A total number of 2540 patients underwent this survey that has included the recording of CT parameters, computed tomography dose index (CTDIvol) and dose-length product of the head, thorax, abdomen, abdomen-pelvis (AP), lumbar spine (LS) and thorax-abdomen-pelvis (TAP) performed on standard patients. The proposed DRLs are 71 mGy/1282 mGy.cm for head, 16 mGy/555 mGy.cm for thorax, 18 mGy/671 mGy.cm for abdomen, 21 mGy/950 mGy.cm for AP, 36 mGy/957 mGy.cm for LS and 18 mGy/994 mGy.cm for TAP. The rounded 75th percentile seems to be higher in some examinations compared to the literature. Our findings confirm the need to optimise our practice. These results provide a starting point for institutional evaluation of CT radiation doses.
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Affiliation(s)
| | - Ahmed Merad
- Département de Physique Médicale, Centre de Recherche Nucléaire d'Alger, Algiers, Algeria
| | - Virginia Tsapaki
- Konstantopoulio General Hospital, Medical Physics Department, Athens, Greece
| | - Fouzia Meddad
- Département de Physique Médicale, Centre de Recherche Nucléaire d'Alger, Algiers, Algeria
| | - Zakia Sakhri-Brahimi
- Département de Physique Médicale, Centre de Recherche Nucléaire d'Alger, Algiers, Algeria
| | - Diana Guedioura
- Département de Physique Médicale, Centre de Recherche Nucléaire d'Alger, Algiers, Algeria
| | - Samia Saadi
- Département de Physique Médicale, Centre de Recherche Nucléaire d'Alger, Algiers, Algeria
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Yurt A, Özsoykal İ, Kandemir R, Ada E. LOCAL STUDY OF DIAGNOSTIC REFERENCE LEVELS FOR COMPUTED TOMOGRAPHY EXAMINATIONS OF ADULT PATIENTS IN İZMIR, TURKEY. RADIATION PROTECTION DOSIMETRY 2020; 190:446-451. [PMID: 32947621 DOI: 10.1093/rpd/ncaa121] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 08/14/2020] [Accepted: 08/16/2020] [Indexed: 06/11/2023]
Abstract
PURPOSE This study aims to develop local diagnostic reference levels (DRLs) for the most common computed tomography (CT) examinations carried out around Izmir, Turkey. METHODS Five common CT examinations (head, neck, chest, abdomen-pelvis (AP), chest-abdomen-pelvis (CAP)) from four different radiology centres have been included in the study. CT dose index-volume (CTDIvol) and dose length product (DLP) values were recorded for 50 patients per exam in each centre. Third quartiles of CTDIvol and DLP values were determined as DRLs and compared with international findings. RESULTS 51.3% of the patients were male and 48.7% were female, with a mean age of 57 (between 18 and 93). DRLs for CTDIvol were recorded as 70, 16, 15, 23 and 16 for head, neck, chest, AP and CAP examinations, respectively, while the corresponding DLPs were 1385, 604, 567, 998 and 1180 mGy.cm. CONCLUSION Results are mostly comparable to the latest international data, except for the head examinations, which were observed to slightly exceed the DRLs established by other countries.
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Affiliation(s)
- Ayşegül Yurt
- Department of Medical Physics, The Health Sciences Institute, Dokuz Eylül University, Balçova, İzmir, Turkey
- The Vocational School of Health Services, Dokuz Eylül University, Balçova, İzmir, Turkey
| | - İsmail Özsoykal
- Department of Medical Physics, The Health Sciences Institute, Dokuz Eylül University, Balçova, İzmir, Turkey
| | - Recep Kandemir
- Department of Medical Physics, The Health Sciences Institute, Dokuz Eylül University, Balçova, İzmir, Turkey
| | - Emel Ada
- Department of Radiology, Faculty of Medicine, Dokuz Eylül University, Balçova, İzmir, Turkey
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Yang CC. Evaluation of Impact of Factors Affecting CT Radiation Dose for Optimizing Patient Dose Levels. Diagnostics (Basel) 2020; 10:E787. [PMID: 33028021 PMCID: PMC7600150 DOI: 10.3390/diagnostics10100787] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 09/30/2020] [Accepted: 10/03/2020] [Indexed: 11/16/2022] Open
Abstract
The dose metrics and factors influencing radiation exposure for patients undergoing head, chest, and abdominal computed tomography (CT) scans were investigated for optimization of patient dose levels. The local diagnostic reference levels (DRLs) of adult CT scans performed in our hospital were established based on 28,147 consecutive examinations, including 5510 head scans, 9091 chest scans, and 13,526 abdominal scans. Among the six CT scanners used in our hospital, four of them are 64-slice multi-detector CT units (MDCT64), and the other two have detector slices higher than 64 (MDCTH). Multivariate analysis was conducted to evaluate the effects of body size, kVp, mAs, and pitch on volume CT dose index (CTDIvol). The local DRLs expressed in terms of the 75th percentile of CTDIvol for the head, chest, and abdominal scans performed on MDCT64 were 59.32, 9.24, and 10.64 mGy, respectively. The corresponding results for MDCTH were 57.90, 7.67, and 9.86 mGy. In regard to multivariate analysis, CTDIvol showed various dependence on the predictors investigated in this study. All regression relationships have coefficient of determination (R2) larger than 0.75, indicating a good fit to the data. Overall, the research results obtained through our workflow could facilitate the modification of CT imaging procedures once the local DRLs are unusually high compared to the national DRLs.
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Affiliation(s)
- Ching-Ching Yang
- Department of Medical Imaging and Radiological Sciences, Kaohsiung Medical University, Kaohsiung 80708, Taiwan;
- Department of Medical Research, Kaohsiung Medical University Chung-Ho Memorial Hospital, Kaohsiung 80708, Taiwan
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Computed tomography diagnostic reference levels for adult brain, chest and abdominal examinations: A systematic review. Radiography (Lond) 2020; 27:673-681. [PMID: 32948454 DOI: 10.1016/j.radi.2020.08.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 08/16/2020] [Accepted: 08/28/2020] [Indexed: 11/22/2022]
Abstract
OBJECTIVES Radiation dose variation within and among Computed Tomography (CT) centres is commonly reported. This work systematically reviewed published articles on adult Diagnostic Reference Levels (DRLs) for the brain, chest and abdomen to determine the causes and extent of variation. A systematic literature search and review was performed in selected databases containing leading journals in radiography, radiology and medical physics using carefully defined search terms related to CT and DRLs. The quality of the included articles was determined using the Effective Public Health Practise Project tool for quantitative studies. KEY FINDINGS The 54 articles reviewed include: 45 studies using human data, 8 studies using phantom data, and one study with both human and phantom data. The main comparator in between studies was the dose indices used in reporting DRLs. DRL variations of up to a factor of 2 for the same procedure were noted in phantom studies, and up to a factor of 3 in human studies. Sources of variation include the type of scanner, the age of the scanner, differences in protocols, variations in patients, as well as variations in study design. Different combinations of dose indices were reported: volume computed tomography dose index (CTDIvol) and dose length product (DLP) (59%); DLP only (11%); weighted computed tomography dose index (CTDIw) and DLP (9%); CTDIvol only (7%); CTDIvol, DLP and effective dose (ED) (6%); CTDIw only (4%); CTDIvol, DLP and size specific dose estimate (SSDE) (1%) and CTDIw, CTDIvol and DLP (1%). The use of different dose indices limited dose comparison between studies. CONCLUSION The study noted a 2-3 fold variation in DRLs between studies for the same procedure. The causes of variation are reported and include study design, scanner technology and the use of different dose indices. IMPLICATIONS FOR PRACTICE There is a need for standardisation of CT DRLs in line with the International Commission on Radiological Protection recommendations to reduce dose variation and facilitate dose comparison.
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Awad MF, Karout L, Arnous G, Rawashdeh MA, Hneiny L, Saade C. A systematic review on the current status of adult diagnostic reference levels in head, chest and abdominopelvic Computed Tomography. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2020; 40:R71-R98. [PMID: 32203948 DOI: 10.1088/1361-6498/ab826f] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Computed tomography (CT) is a routinely employed diagnostic tool for the detection and diagnosis of disease processes. Despite the primary focus of radiation dose reduction and improvements in CT scanners, radiation dose exposure remains an ever-increasing concern. Scanning protocol optimisation relative to body weight and scanner manufacturer still lags behind the diagnostic reference levels (DRLs) that are set on an international scale. The aim of this systematic review is to evaluate the current status of adult DRLs in head, chest and abdominopelvic CT over time on a global scale. A search was carried out in early 2019 using the Medline, PubMed, EMBASE, SCOPUS and manual databases. The reference lists of published articles were also assessed to identify further articles. The preferred reporting items for systematic reviews and meta-analyses (PRISMA) methodology was employed to evaluate articles for relevance. Articles were included if they assessed the DRL in head, chest and abdominopelvic scans. The search resulted in 6079 articles, of which 67 were included after a thorough screening process. The literature demonstrates a wide dose variation in reported head, chest and abdominopelvic dose length product (DLP) DRL, ranging from 700-1359, 330-707 and 550-1486 mGy·cm, respectively. Where reported, the volumed CT dose index (CTDIvol) DRL in the head, chest and abdominopelvic studies ranged from 30.4-85.5, 9-15 and 12.3-31 mGy·cm, respectively. The global means were shown to be slightly lower and significantly lower than the reported values of DLP and CTDIvol values for the American College of Radiology and European Commission, respectively. This review emphasises the need for an international standardisation for head and body DRL establishment methods, to provide a more comparable global measurement of dose variations across CT sites as well as regular monitoring of delivered radiation dose to patients.
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Affiliation(s)
- Mohamad Fawzi Awad
- Medical Imaging Sciences, Faculty of Health Sciences, American University of Beirut, PO Box: 11-0236 Riad El-Solh, Beirut 1107 2020, Lebanon
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Gao Y, Mahmood U, Liu T, Quinn B, Gollub MJ, Xu XG, Dauer LT. Patient-Specific Organ and Effective Dose Estimates in Adult Oncologic CT. AJR Am J Roentgenol 2020; 214:738-746. [PMID: 31414882 PMCID: PMC7393764 DOI: 10.2214/ajr.19.21197] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE. Patient-specific organ and effective dose provides essential information for CT protocol optimization. However, such information is not readily available in the scan records. The purpose of this study was to develop a method to obtain accurate examination- and patient-specific organ and effective dose estimates by use of available scan data and patient body size information for a large cohort of patients. MATERIALS AND METHODS. The data were randomly collected for 1200 patients who underwent CT in a 2-year period. Physical characteristics of the patients and CT technique were processed as inputs for the dose estimator. Organ and effective doses were estimated by use of the inputs and computational human phantoms matched to patients on the basis of sex and effective diameter. Size-based ratios were applied to correct for patient-phantom body size differences. RESULTS. Patients received a mean of 59.9 mGy to the lens of the eye per brain scan, 10.1 mGy to the thyroid per chest scan, 17.5 mGy to the liver per abdomen and pelvis scan, and 19.0 mGy to the liver per body scan. A factor of 2 difference in dose estimates was observed between patients of various habitus. CONCLUSION. Examination- and patient-specific organ and effective doses were estimated for 1200 adult oncology patients undergoing CT. The dose conversion factors calculated facilitate rapid organ and effective dose estimation in clinics. Compared with nonspecific dose estimation methods, patient dose estimations with data specific to the patient and examination can differ by a factor of 2.
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Affiliation(s)
- Yiming Gao
- Department of Medical Physics, Box 84, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - Usman Mahmood
- Department of Medical Physics, Box 84, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - Tianyu Liu
- Department of Mechanical, Aerospace, and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - Brian Quinn
- Department of Medical Physics, Box 84, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - Marc J. Gollub
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - X. George Xu
- Department of Mechanical, Aerospace, and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - Lawrence T. Dauer
- Department of Medical Physics, Box 84, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
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14
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Kim JS, Lee SK, Kim SK, Yoo SM, Kim JM, Yoon SW. NATIONAL DIAGNOSTIC REFERENCE LEVELS AND ACHIEVABLE DOSES FOR 13 ADULT CT PROTOCOLS AND A PAEDIATRIC HEAD CT PROTOCOL: NATIONAL SURVEY OF KOREAN HOSPITALS. RADIATION PROTECTION DOSIMETRY 2019; 187:220-229. [PMID: 31322696 DOI: 10.1093/rpd/ncz156] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 05/06/2019] [Accepted: 05/23/2019] [Indexed: 06/10/2023]
Abstract
To develop a second set of diagnostic reference levels (DRLs) and achievable doses (ADs) for 13 adult computed tomography (CT) protocols and a paediatric head CT protocol in Korea. A survey of 13,625 CT examinations was performed based on 13 adult CT protocols and a paediatric non-contrast brain CT protocol using 369 CT systems, with patients grouped according to age. Most CT protocols in this survey had DRLs similar to those reported in other countries. However, chest and abdomen-pelvic CT had lower DRLs than those reported in the first Korean national survey and those from other countries. Paediatric non-contrast brain CT in each age group, with the exception of the 11-15-year age group, had lower DRLs than those reported in other countries. The DRLs presented here are similar to (or lower than for some protocols) those reported in the first Korean national survey and those from other countries.
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Affiliation(s)
- Jung Su Kim
- Department of Radiologic-Technology, Daegu Health College, Daegu, Korea
| | - Sang Kyung Lee
- Department of Bio-convergence Engineering, Graduate school, Korea University, Seoul, Korea
| | - Sun-Ki Kim
- Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
| | - Seung-Min Yoo
- Department of Diagnostic Radiology, CHA Bundang Medical Center, CHA University, Seongnam, Korea
| | - Jung Min Kim
- Department of Bio-convergence Engineering, Graduate school, Korea University, Seoul, Korea
| | - Sang-Wook Yoon
- Department of Diagnostic Radiology, CHA Bundang Medical Center, CHA University, Seongnam, Korea
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15
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Ebrahimi-Khankook A, Akhlaghi P, Vejdani-Noghreiyan A. Studying the lung dose uncertainty during chest CT scans using phantoms with statistical lung volumes and shapes. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2019; 39:443-454. [PMID: 30673649 DOI: 10.1088/1361-6498/ab0116] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
In recent years, there has been increasing interest in constructing a series of deformable phantoms which follow the statistical distributions of some anatomical variations, known as 'statistical phantoms'. The main purpose of this study was to develop statistical phantoms by considering the variations in lung volume and shape, in order to evaluate the lung dose uncertainty for individuals undergoing chest computed tomography. Calculations were performed for 100 statistical lung volume phantoms and 70 statistical lung shape phantoms at tube voltages of 80 and 120 kVp, with the use of Monte Carlo MCNP code. The obtained results indicate that dose fluctuations for low tube voltage (80 kVp) are higher than those at 120 kVp. Moreover, it shows that the impact of statistical variations in lung volume on dose discrepancy (5% to 7%) is higher than the impact of statistical lung shape variations (around 2%).
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16
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Lv P, Zhou Z, Liu J, Chai Y, Zhao H, Guo H, Marin D, Gao J. Can virtual monochromatic images from dual-energy CT replace low-kVp images for abdominal contrast-enhanced CT in small- and medium-sized patients? Eur Radiol 2018; 29:2878-2889. [DOI: 10.1007/s00330-018-5850-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 09/29/2018] [Accepted: 10/22/2018] [Indexed: 01/25/2023]
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17
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Ekpo EU, Adejoh T, Akwo JD, Emeka OC, Modu AA, Abba M, Adesina KA, Omiyi DO, Chiegwu UH. Diagnostic reference levels for common computed tomography (CT) examinations: results from the first Nigerian nationwide dose survey. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2018; 38:525-535. [PMID: 29376504 DOI: 10.1088/1361-6498/aaaaf8] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
PURPOSE To explore doses from common adult computed tomography (CT) examinations and propose national diagnostic reference levels (nDRLs) for Nigeria. MATERIALS AND METHODS This retrospective study was approved by the Nnamdi Azikiwe University and University Teaching Hospital Institutional Review Boards (IRB: NAUTH/CS/66/Vol8/84) and involved dose surveys of adult CT examinations across the six geographical regions of Nigeria and Abuja from January 2016 to August 2017. Dose data of adult head, chest and abdomen/pelvis CT examinations were extracted from patient folders. The median, 75th and 25th percentile CT dose index volume (CTDIvol) and dose-length-product (DLP) were computed for each of these procedures. Effective doses (E) for these examinations were estimated using the k conversion factor as described in the ICRP publication 103 (EDLP = k × DLP). RESULTS The proposed 75th percentile CTDIvol for head, chest, and abdomen/pelvis are 61 mGy, 17 mGy, and 20 mGy, respectively. The corresponding DLPs are 1310 mGy.cm, 735 mGy.cm, and 1486 mGy.cm respectively. The effective doses were 2.75 mSv (head), 10.29 mSv (chest), and 22.29 mSv (abdomen/pelvis). CONCLUSION Findings demonstrate wide dose variations within and across centres in Nigeria. The results also show CTDIvol comparable to international standards, but considerably higher DLP and effective doses.
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Affiliation(s)
- Ernest U Ekpo
- Faculty of Health Sciences, The University of Sydney, Discipline of Medical Radiation Sciences, Cumberland Campus, 75 East Street, Lidcombe, NSW 2141, Australia
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18
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Diagnostic Reference Levels for Adult Patients in the United States. J Am Coll Radiol 2018; 15:932-933. [DOI: 10.1016/j.jacr.2017.12.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 12/07/2017] [Indexed: 11/23/2022]
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19
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Roch P, Célier D, Dessaud C, Etard C. Using diagnostic reference levels to evaluate the improvement of patient dose optimisation and the influence of recent technologies in radiography and computed tomography. Eur J Radiol 2018; 98:68-74. [DOI: 10.1016/j.ejrad.2017.11.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 09/26/2017] [Accepted: 11/06/2017] [Indexed: 10/18/2022]
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20
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Rafat Motavalli L, Hoseinian Azghadi E, Miri Hakimabad H, Akhlaghi P. Pulmonary embolism in pregnant patients: Assessing organ dose to pregnant phantom and its fetus during lung imaging. Med Phys 2017; 44:6038-6046. [PMID: 28869670 DOI: 10.1002/mp.12558] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 07/24/2017] [Accepted: 08/25/2017] [Indexed: 11/10/2022] Open
Abstract
PURPOSE The purpose of this study was to provide updated radiation dose from diagnostic exams performed for pregnant patients suspected of pulmonary embolism (PE) using the recently developed BREP phantoms of pregnant woman and the fetus. Also to challenge the validity of current recommendations suggest that ventilation/perfusion (V/Q) single photon emission computed tomography (SPECT) vs. computed tomography pulmonary angiography (CTPA) should be considered for diagnosis of PE in radiosensitive groups such as pregnant women. METHODS The Monte Carlo calculations involving detailed geometrical simulation of pregnant women and the fetus were performed. RESULTS The results showed that when radiation dose to the fetus is of concern, CTPA is more appropriate at early stages causes 50%-97% lower fetal doses for the first two trimesters of pregnancy. While for gestational periods more than 6 months, V/Q SPECT leads to a 15% lower fetal dose and thus, is less hazardous. The fetal dose from CTPA increases with gestational age, while that from V/Q SPECT decreases. Furthermore, the maximum amount of fetal dose is received by fetal skeleton (i.e., on average about 1.8 and 3.9 times larger dose from SPECT and CT, respectively). CONCLUSIONS V/Q SPECT should not always be preferred for pregnant patients suspected of PE. This finding is in contrast with the guidance to choose the preferred modality based on the maternal effective dose. The reason of this issue was discussed in this paper based on chord length distributions (CLDs). The importance of considering fetal organs separately in MC calculations was also highlighted.
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Affiliation(s)
- Laleh Rafat Motavalli
- Physics Department, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, Iran
| | | | - Hashem Miri Hakimabad
- Physics Department, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Parisa Akhlaghi
- Department of Medical Physics, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
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21
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Kanal KM, Butler PF, Sengupta D, Bhargavan-Chatfield M, Coombs LP, Morin RL. U.S. Diagnostic Reference Levels and Achievable Doses for 10 Adult CT Examinations. Radiology 2017; 284:120-133. [DOI: 10.1148/radiol.2017161911] [Citation(s) in RCA: 181] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Kalpana M. Kanal
- From the Department of Radiology, University of Washington, Seattle, Wash (K.M.K.); Departments of Quality and Safety (P.F.B., M.B.) and National Radiology Data Registries (D.S., L.P.C.), American College of Radiology, 1891 Preston White Dr, Reston, VA 20191; and Department of Radiology, Mayo Clinic Florida, Jacksonville, Fla (R.L.M.)
| | - Priscilla F. Butler
- From the Department of Radiology, University of Washington, Seattle, Wash (K.M.K.); Departments of Quality and Safety (P.F.B., M.B.) and National Radiology Data Registries (D.S., L.P.C.), American College of Radiology, 1891 Preston White Dr, Reston, VA 20191; and Department of Radiology, Mayo Clinic Florida, Jacksonville, Fla (R.L.M.)
| | - Debapriya Sengupta
- From the Department of Radiology, University of Washington, Seattle, Wash (K.M.K.); Departments of Quality and Safety (P.F.B., M.B.) and National Radiology Data Registries (D.S., L.P.C.), American College of Radiology, 1891 Preston White Dr, Reston, VA 20191; and Department of Radiology, Mayo Clinic Florida, Jacksonville, Fla (R.L.M.)
| | - Mythreyi Bhargavan-Chatfield
- From the Department of Radiology, University of Washington, Seattle, Wash (K.M.K.); Departments of Quality and Safety (P.F.B., M.B.) and National Radiology Data Registries (D.S., L.P.C.), American College of Radiology, 1891 Preston White Dr, Reston, VA 20191; and Department of Radiology, Mayo Clinic Florida, Jacksonville, Fla (R.L.M.)
| | - Laura P. Coombs
- From the Department of Radiology, University of Washington, Seattle, Wash (K.M.K.); Departments of Quality and Safety (P.F.B., M.B.) and National Radiology Data Registries (D.S., L.P.C.), American College of Radiology, 1891 Preston White Dr, Reston, VA 20191; and Department of Radiology, Mayo Clinic Florida, Jacksonville, Fla (R.L.M.)
| | - Richard L. Morin
- From the Department of Radiology, University of Washington, Seattle, Wash (K.M.K.); Departments of Quality and Safety (P.F.B., M.B.) and National Radiology Data Registries (D.S., L.P.C.), American College of Radiology, 1891 Preston White Dr, Reston, VA 20191; and Department of Radiology, Mayo Clinic Florida, Jacksonville, Fla (R.L.M.)
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22
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Diagnostic Reference Levels and Monitoring Practice Can Help Reduce Patient Dose From CT Examinations. AJR Am J Roentgenol 2017; 208:1073-1081. [PMID: 28245142 DOI: 10.2214/ajr.16.16361] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE The purpose of this study is to establish provincial diagnostic reference levels (DRLs) and to determine whether this process may help reduce the patient radiation dose from the most frequently performed CT examinations. MATERIALS AND METHODS We investigated the following CT examinations: head, chest, low-dose chest, abdomen and pelvis, and chest, abdomen, and pelvis examinations. The sample for each protocol included 15 patients of average body weight (mean [± SD], 70 ± 20 kg). The differences in dose between scanners were evaluated using one-way ANOVA. Correlations between dose, scanner age, and the number of detector rows were assessed using the Pearson correlation coefficient. A sample of abdominal and chest examinations were randomized and blinded for review by experienced radiologists who graded diagnostic image quality. Provincial DRLs were calculated as the 75th percentile of patient dose distributions. For hospitals with doses exceeding the DRLs, dose reduction was recommended, followed by another survey. RESULTS The initial survey included data of 1185 patients, and an additional 180 patients were surveyed after protocol optimization. The differences between the mean values of the dose distributions from each scanner were statistically significant (p < 0.05) for all examinations. The variation was greatest for low-dose chest CT, with a greater than fivefold difference in the mean dose values noted between scanners. A very weak correlation was found between dose and scanner age or the number of detector rows. Analysis of image quality revealed no statistically significant differences in any scoring categories, with the exception of the noise category in abdominal imaging. Implementation of the DRLs allowed a reduction in patient dose of up to 41% as a result of a protocol change. CONCLUSION Establishing provincial DRLs allows an effective reduction in patient dose without resulting in degradation of image quality.
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