City Research Online

Abstract

Introduction: While many European and American countries have established national diagnostic reference levels (NDRLs), few African countries have. Therefore, this study aimed to propose adult NDRLs for common computed tomography (CT) examinations in Zambia.

Methods: 1360 CT patient data for the brain, chest, abdomen and pelvis were collected from 10 public CT facilities. The CT images were assessed for acceptable image quality and patient anthropometry was done, with patients' anteroposterior diameter used as the patient parameter. NDRLs were set at the 75th percentile of the distribution of volume-based CT dose index (CTDIvol) and dose length product (DLP) and were compared to countries’ NDRLs.

Results: NDRLs for CTDIvol in mGy were calculated as follows; non-contrast brain 70.5, contrast brain 56.74, non-contrast chest 20.24, contrast chest 20, non-contrast abdomen/pelvis, 21.3, contrast abdomen/pelvic 21.3, non-contrast chest/abdomen/pelvis 20 and contrast chest/abdomen/pelvis 19.1. The corresponding NDRLs for DLP in mGy.cm are 1455, 1206, 745.8, DLP 666.7, 1103, 1103, 1237 and 1141. Variations in DLP values between facilities were statistically significant (p <0.0001). NDRLs for the brain and chest were higher than those from other countries but lower for the abdomen/pelvis and chest/abdomen/pelvis. Correlations between the CT scanner’s number of detector rows and CTDIvol were (r = 0.08285, p <0. 0.0022) and (r = 0.5038, p <0.0001) between patients’ AP diameter and CTDIvol.

Conclusion: The proposed NDRLs confirmed the need to optimise CT scan parameters and protocols in Zambia. Therefore, extensive training of all CT radiographers in optimising CT image acquisition parameters and regular dose audits is recommended.

Implication of practice: NDRLs will likely provide a benchmarking mechanism for dose optimisation practices among CT radiographers in Zambia and beyond.

Publication Type:	Article
Additional Information:	© 2025. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/
Publisher Keywords:	Computed tomography, Diagnostic reference level, Volume-weighted computed tomography dose index, Dose length product, Zambia
Subjects:	D History General and Old World > DT Africa R Medicine > RA Public aspects of medicine > RA0421 Public health. Hygiene. Preventive Medicine R Medicine > RC Internal medicine
Departments:	School of Health & Medical Sciences School of Health & Medical Sciences > Midwifery & Radiography
SWORD Depositor:	Symplectic Administrator

Export

Downloads