Dose versus diagnosis: Iatrogenic radiation exposure by multidetector computerised tomography in an academic emergency department with measurement of clinically actionable results and emergently treatable findings

Aim: To determine the iatrogenic absorbed dosage of radiation of the patient in milligray (mGy) computerised tomography dose index volume (CTDIvol) when tested with multidetector computerised tomography (MDCT) in the emergency department (ED) setting and calculate the absorbed dosage of radiation per clinically actionable result and emergently treatable finding (ETF). Setting: The University of Texas Medical Branch (UTMB) ED located in Galveston, Texas, USA, is a level 1 trauma and tertiary referral centre treating 70 000 patients per annum. Method: A retrospective cross-sectional data analysis of 770 emergency patients investigated by MDCT in July 2007. The presence of actionable results and ETF were determined by chart review. Results: A total of 5320 emergency patients was treated in the UTMB ED in July 2007. This included 4508 medical and 812 trauma patients. A total of 1094 MDCT studies was performed, of which complete data were available on 1046. A total of 770 patients was investigated by MDCT, representing 14.47% of all emergency patients. This included 33.99% of trauma patients and 10.96% of medical patients. Actionable results were found in 341 studies and ETF in 105 studies. The mean radiation was 163.27 and 530.23 mGy CTDIvol for actionable results and ETF, respectively, for all studies. The mean radiation was 53.27 and 106.36 mGy CTDIvol for medical and trauma patients, respectively. Conclusions: The absorbed dosage of radiation of patients investigated by MDCT is clinically significant. The actionable results and ETF in our study demonstrate considerable opportunity for improvement in the utilisation of this technology by physicians.