Reduction of radiation dose in pediatric brain CT is not associated with missed injuries or delayed diagnosis

Increased accuracy of CTs in the identification of traumatic injuries compared with physical examination or conventional radiography is well documented. Our goal was to identify the most effective strategy for decreasing radiation exposure while retaining the benefits of computerized imaging. Based on a literature review and our trauma registry, the mortality risk of untreated injuries was compared with that of patients who received treatment of injuries diagnosed by CT. Because automated exposure control of tube current is not routinely used with brain CT, this region was identified as the initial focus for a dose-saving algorithm. CTsettings were adjusted for children studies and the new settings were implemented into four protocols based on age. Images were compared and reviewed by radiologists for the ability to identify traumatic injuries. Effective dose (ED) was estimated using Monte Carlo simulations. The lifetime incidence and mortality for thyroid cancer and leukemia were assessed. In-hospital mortality of unidentified injury in trauma patients is 8.0%. Forty dose-saving CTs were performed and no injuries were missed. The ED decreased by 5.2-, 4.5-, 2.62-, and 2.5-fold in each group. Decreasing the ED is achievable, theoretically decreases the cancer risk and does not increase the missed injury rate.