Justifying referrals for paediatric CT

The system of radiation protection assumes a linear dose response relationship with no threshold for tow doses and dose rate exposures. This is based on epidemiological evidence at higher doses. Hence there is a small theoretical risk of carcinogenesis attributable to low doses of ionising radiation. This risk is associated with any diagnostic imaging procedure involving radiation. Radiosensitivity declines with age, so children are more susceptible to radiation risks than adults. Females are more radiosensitive than males. The radiation protection system is based on the assumption that radiation risk is cumulative over a lifetime. For an individual, a justified, optimised computed tomography (CT) scan will result in more benefit than harm. A doctor must justify the necessity for a CT scan before referring an individual for imaging.