Evaluation of radiation dose parameters during exposure in cerebral computed tomography angiography

Abstract

This study aimed to evaluate the radiation doses for patients during cerebral angiographic computed tomography (CTA) scans using two multidetector CT scanners (MDCTs), to reduce these doses, and to determine institutional diagnostic reference levels (iDRLs). A total of 244 patients were included in the study; 131 (53.7%) were examined using the routine protocol, whereas 113 (46.3%) underwent the dose reduction protocol. All examinations were carried out using two 64-slice MDCT scanners at the radiology department of a Southern-Region of Saudi Arabia hospital: a GE Healthcare, and Siemens scanners. Dose length product (DLP, mGy.cm) and mean volume CT dose index (CTDI, mGy) were used as the dose descriptors according to the International Commission on Radiological Protection (ICRP) recommendations. Data were analyzed using IBM SPSS Statistics (version 26). The overall iDRLs for CTDI_vol and DLP were 64.9 mGy and 2184.4 mGy cm, respectively. These iDRLs, particularly for the DLP, were higher than the reference values for individual CT scans in Saudi Arabia (1026 mGy.cm) as proposed by the Saudi Food and Drug Administration (SFDA), which potentially indicated that these patients had undergone multiple or complex procedures. Notably, the overall radiation burdens were considerably influenced by variables other than age, gender, or duration of exposure. To maintain the minimum dose requirements without compromising diagnostic accuracy, these findings highlight the importance of focusing on the cumulative DLP, particularly for repeated or prolonged scans. The findings also stress the need for the regular review and updating of imaging methods and provide vital information for improving CT procedures and enhancing patient safety by using more effective dose reduction techniques.