Diagnostic reference levels for common computed tomography (CT) examinations: results from the first Nigerian nationwide dose survey
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 (CTDI vol ) 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 (E DLP = k × DLP ). Results . The proposed 75th percentile CTDI vol 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 CTDI vol comparable to international standards, but considerably higher DLP and effective doses.
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The primary factors influencing CT dose variation are multi-phase scanning and institutional protocol choices.
“Other scholars have opined that CT scan doses vary considerably within and across facilities; the primary factors influencing dose variation are multi-phase scanning and institutional protocol choices.”
From Adult Computed Tomography examinations in Uganda: Towards determining the National Diagnostic Reference Levels (2022) · cites this paper as [11]
CT scan doses vary considerably within and across facilities.
“Other scholars have opined that CT scan doses vary considerably within and across facilities; the primary factors influencing dose variation are multi-phase scanning and institutional protocol choices.”
From Adult Computed Tomography examinations in Uganda: Towards determining the National Diagnostic Reference Levels (2022) · cites this paper as [11]
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“It is however not clear whether these are the same factors in play in resourcelimited settings like Uganda [11].”
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- Authors
- Ekpo, E. U., Adejoh, T., Akwo, J. D., Emeka, O. C., Modu, A. A., Abba, M., Adesina, K. A., Omiyi, D. O., & Chiegwu, U. H.
- Affiliations
- The University of Sydney (AU)
- Nnamdi Azikiwe University (NG)
- University of Calabar (NG)
- National Hospital Abuja (NG)
- Bayero University Kano (NG)
- University of Lagos (NG)
- Corresponding author
- Ekpo, Ernest U
- Venue
- Journal of Radiological Protection
- Publisher
- IOP Publishing
- Published
- 2018-03-13
- Volume
- 38
- Issue
- 2
- Pages
- 525-535
- ISSN
- 0952-4746 (ISSN-L)
- 1361-6498
- OpenAlex
- W2793265424
- Cited by
- 61
- References
- 36
- Citations by year
- 2026: 2 · 2025: 7 · 2024: 8 · 2023: 5 · 2022: 11 · 2021: 13 · 2020: 10 · 2019: 4 · 2018: 1
- FWCI
- 4.83
- Type
- journal article
- Language
- en
- Open access
- closed
- Licence
- Locations
- Journal of Radiological Protection (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Health Sciences › Medicine › Radiology, Nuclear Medicine and Imaging › Radiation Dose and Imaging
- Physical Sciences › Physics and Astronomy › Radiation › Advanced Radiotherapy Techniques
- Health Sciences › Medicine › Radiology, Nuclear Medicine and Imaging › Radiology practices and education
- Keywords
- diagnostic reference levels, computed tomography, radiation dose, volume CT dose index, dose-length product, effective dose, head CT, chest CT, abdomen-pelvis CT, Nigeria
- MeSH terms
- Adult, Aged, Aged, 80 and over, Female, Humans, Male, Middle Aged, Nigeria, Radiation Dosage, Reference Values, Retrospective Studies, Tomography, X-Ray Computed, Health Care Surveys, Young Adult
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