Establishment of Regional Diagnostic Reference Levels in Adult Computed Tomography for Four African Countries: A Preliminary Survey

Abstract

This preliminary study aims towards the establishment of regional diagnostic reference levels (DRLs) for routine adult computed tomography (CT) examinations. The study was performed on 54 CT facilities from four African countries (Ghana, Kenya, Namibia and Senegal) and the results compared with international DRLs. Data were collected from facilities using a structured questionnaire provided by the International Atomic Energy Agency. Dose descriptors (volume computed tomography dose index [CTDIvol] and dose length product [DLP]) evaluations were performed on CT head and body phantoms for head, chest and abdomen CT examination protocols using standard methods. The estimated dose indices were compared with console-displayed dose values. Experienced radiologists accepted the diagnostic image quality of the images as per departmental imaging requirements. Median CTDIvol and DLP data from each facility were compiled to estimate the typical dose in each country. National DRLs were established based on the 75th percentile of median values, whereas the regional DRLs were based on the median of the national DRLs. Comparison of measured CTDIvol with console values of all facilities in all four countries was within 20% as recommended. The established CTDIvol DRLs for head CT, chest CT and abdomen CT were 60.9 mGy, 15.2 mGy and 15.7 mGy, respectively. Similarly, that of DLP, DRLs were 1259 mGy.cm, 544 mGy.cm and 737 mGy.cm, respectively for head CT, chest CT and abdomen CT. The established DRLs from this study were comparable to DRLs from other countries with some variations. This study would serve as baseline for establishment of a more generalized regional adult CT DRLs for Africa.

A Comparison of the Mean CTDIvol and DLP Values for Adult Abdominal CT Examination for MTRH, Eldoret Hospital, St. Luke’s Hospital and Mediheal Hospital: A Retrospective Study

“…This suggests that most of the installation of CT scan across the public and private hospital have been made in recent years. Similar observation were made by 7 who suggested that the number of CT scanners in direct medical use in Kenya increased by over 80 % in the past decade (2012-2019). The overall increase in the number of CT scans between 2016 and 2018 can, to a large extent, be attributed to the MES, a public-private partnership project (PPP) introduced in 2016, that has equally resulted in availability of more imaging modalities in the public sector.…”

Science diplomacy in medical physics – an international perspective

“…IAEA and African experts established the first harmonized imaging quality control protocols for Africa in 2020 to help achieve a minimum standard throughout the region [ 22 ]. An initial study on regional diagnostic reference levels for computed tomography included data from Ghana, Kenya, Namibia, and Senegal [ 23 ] indicating that regional collaboration is expanding. Results of studies like these may eventually trickle down into national regulations or similar.…”