Analysis of CT-related sites and effective dose in children

Objective: To analyze the sites of CT scan and radiation dose to children, and to compare the dose difference between children and others aged above 14 years with the dose-monitoring software in a single scan. Methods: A total of 125 147 cases undergoing CT scans were selected from Jan 1 to Dec 31, 2016, including 542 in children group and 124 605 in patients group aged above 14 years. Based on the self-designed CT dose of real-time detection and management software, the scan sites and the composition of the scanning dose were recorded and compared between children and patients aged above 14 years in a single scan. Results: Head (39.67%) and extremities (36.90%) were the primary CT scan sites in children. Abdominal (20.77%) and limbs (48.87%) constituted the main part of effective dose to children. In children group, the average single DLP gradually increased with age(Z = 21.42, P < 0.05). The mean DLP was (567.38 ± 433.03) mGy·cm and average effective dose (5.58 ± 5.45) mSv in children group, significantly lower than that in patients aged above [14 years (737.75 ± 172.40) mGy·cm and (11.07 ± 2.59) mSv, Z = -3.74, -4.12, P < 0.05]. DLPs in patients aged above 14 years were higher than or equal to those in children group, with a few exceptions of neck and limbs with higher values(Z = -2.04, -3.97, P < 0.05). Effective doses in children were higher than or equal to those in the group aged above 14 years(Z = -3.03, -3.11, -4.12, P < 0.05), with an exception of chest with higher value. Conclusions: Although the parameters of CT scan and dose control were optimized to some extent in children, radiation protection on children still needs to be paid attention for due to the radiosensitivity of children. CT scanning on children should be more careful. (authors)