Paediatric Patients Dose Optimisation and Risk Assessment in Computed Tomography Examination

Abstract Children are a distinct group of patients and should not be consider as small adults in terms of medical imaging procedures. Their size, physiology and the location of their organs change as they grow. Additionally, children have a longer life expectancy than adults hence consideration must be taken into account when the appropriate radiation dose is delivered. Therefore, the study was to estimate paediatric patients’ lifetime attributable radiation risk and dose optimisation during computed tomography examination. The materials used include five different multi-detector computed tomography (MDCT) Machines, Head and Body phantom and MeVisLab (MVL) workstation. The methodology involved using weighted CTDI (CTDIW) and DLP values to estimate effective and organ dose in relation to image quality in term of SNR. In addition to the use of the estimated dose values to estimate paediatric patients’ lifetime attributable radiation risk during CT examination. In all 300 dose reports with their corresponding images of randomly selected paediatric patients undergoing CT scans of head, chest, and abdomen-Pelvis from the CT centres were collected from various CT facilities across the country. 200 of these met the selection criterion and has been analysed. The average values for organ dose and effective dose for Brain CT exam for age 0–5, 6–10 and 11–16 years were10.3mGy, 1.3965mSv; 11.18mGy, 2.2785mSv; and 19.82mGy, 4.5102mSv respectively for male patients. While the corresponding image quality for age 0–5, 6–10 and 11–16 years were 8.19; 12.08; and 17.42 respectively. These increasing trends were observed in the Chest and abdominal pelvis examinations, with the dose increasing with an increasing age based on the paediatric age and protocol that were used. the study also established a minimum SNR value of 5.1 with a corresponding minimum effective dose values of 5.8 for a balance between the minimum image quality to the minimum dose to the paediatric patient. The average cancer risk for incidence and mortality for head, chest and abdomen-pelvis examinations were in the range 1 in 10,000 to in 1,000 of the study population.