Evaluation of age-based radiation dose in paediatric patients received from head CT examination at a tertiary hospital, Nigeria

Abstract

Abstract Paediatric computed tomography (CT) imaging though requested less than adult CT but has shown remarkable growth with raising concerns of increased radiation risk to the paediatric population. This study aims to evaluate age-based radiation dose from paediatric head CT scans at a single centre in Nigeria. This study evaluated 233 paediatric aged 0‒15 years and were classified into four age groups; Group 1 (≤1 year), Group 2 (2‒5 years), Group 3 (6‒10 years) and Group 4 (11‒15 years). Patient dose and related scanning protocol data were retrospectively retrieved from the CT scanner. The local dose values were calculated as 25th and 75th percentiles of the distribution of the volume CT dose index (CTDIvol), dose length product (DLP) and effective dose per age-group. These values were compared with the recommended international diagnostic reference levels (DRLs). The estimated dose values were within limits for the youngest age group (≤1 year old) but showed a clear trend towards higher doses for other age groups as compared with DRLs. The relative difference for CTDIvol and DLP were ranged between 0‒45% and 8– 64%, respectively. The largest difference in DRLs was seen in Group 3 and 4. The dose values were increased with the increasing age; Group 1 received the lowest doses (20mGy, 345 mGy.cm, and 3.2 mSv) and Group 4 received the highest doses (61 mGy, 1497 mGy.cm, and 4.4 mSv). The local doses were substantially higher than the international DRLs values except for age group ≤ 1 year, demonstrating a necessity for dose optimization and modification of current acquisition technique towards the reduction of radiation dose among paediatric population.