BACKGROUND: Advanced diagnostic imaging has provided tremendous benefits; 
however, increased use of ionizing radiation modalities such as cranial computed 
tomography (CT) may be associated with an increased risk of developing central 
nervous system tumors.
METHODS: A literature review identified studies published for more than the last 
50 years from 1968 to 2018 that explored the association between head CT scans 
and developing central nervous system tumors in pediatrics. We reviewed seven 
studies that described and analyzed the risk of brain tumors.
RESULTS: A positive correlation between exposure to CT scans and developing 
central nervous system tumors was evident in all cohorts. The strength of the 
association varied across the studies. Exclusion of patients with predisposing 
factors to central nervous system tumors was examined in four studies with a 
decreased risk to develop central nervous system tumors noted in three studies. 
Two studies reported nonsignificant reduction in the excess relative risk per 
milliGray of brain dose after adjusting for predisposing factors, whereas the 
reduction was significant in one study. The frequency of CT exposure was 
proportional to the risk of developing tumors in two studies although not 
significantly maintained in two other studies. Gender had no significant effect 
on the central nervous system tumor risk. The calendar year at the time of 
imaging showed decreasing risk in those exposed to CT in more recent years 
compared with prior decades.
CONCLUSIONS: Prospective epidemiologic studies are needed to examine the precise 
carcinogenic effect of exposure to ionizing radiation and help tailor further 
preventive measures.