Dosimetric assessment in pediatric brain CT scans in Douala (Cameroon): a retrospective study in two referral hospitals

Abstract

Background: Computed tomography (CT) is the modality that delivers the highest radiation in medicine. The purpose of this study was to evaluate these radiation doses in children undergoing brain CT scans in Douala city.

Methods: a retrospective study over three months in two reference hospitals. Children who underwent a cerebral CT scan were randomly included using a 2/3 sampling method. Sociodemographic and clinical data of 38 children, as well as CT dose reports, were collected and analyzed with a significance threshold of p<0.05.

Results: the mean age was 7.9±4.9 (0-15) years, with the most represented age group being 11-15 years (39.5%). The sex-ratio was 1.4. The main indications were head trauma (31.6%) and evaluation of headaches (23.7%). The mAs ranged from 250 to 400 and increased with age group. The voltage ranged from 100 to 140kV (122.6±9.5kV). Thirty-one CT-scans (81.6%) were conforms with a voltage≤120Kv. This compliance rate varied from 66.7% to 100%. The mean CTDIvol was 48.7±31.3 mGy (7.3-111.4 mGy), and the DLP ranged from 113 to 1608.7 mGy·cm (786.1±426.8) with a significant difference between the two hospitals (p=0.04). These doses values showed an increasing trend proportional to the age groups and were higher than the DRLs for almost all pediatric groups (p=0.045).

Conclusion: Radiation levels in pediatric cranial CT scans in Douala's referral hospitals are globaly higher than international recommendations. Better awareness of adjusting acquisition parameters and greater implementation of technical protocols would allow a good dose optimization in CT scans for these young patients.