Scatter Radiation Absorbed Dose Distribution in Coronary Angiography: A Measurement-Based Study

Introduction: This study aimed to investigate the absorbed dose of scatter radiation in coronary angiography.Material and Methods: The scatter radiation dose was measured for ۲۰ patients at four different heights (۵۰,۱۰۰, ۱۵۰, and ۱۶۵ cm) from the floor. The spatial dose was measured by RTI Piranha r۱۰۰b solid-state dose probe at different points around the patient in an actual clinical situation and with a phantom. Also, the measurement was repeated using a designed phantom in fluoroscopy and cine mode in posterior anterior (PA), left lateral (LLAT), left posterior oblique (LPO۴۵°), right posterior oblique (RPO۴۵°), and right-lateral (RLAT)projections . Organ-absorbed doses were normalized to dose area product (DAP).  Results: The dose rate at different heights between the projections on the patient and the phantom as well as organ dose DAP conversion coefficients were different (p˂۰.۰۵). It was found that the dose rate changes in fluoroscopic mode compared to cine mode are significantly different (p = ۰.۰۰۱). The dose rate in cine mode is approximately four times that in fluoroscopy mode. The dose rate around the cardiologist's waist could be reduced by ۳۷ – ۴۳ % with a displacement of ۲۰cm away. In this study, the effective dose rate received by the cardiologist’s eyes was higher than those reported by ICRP.Conclusion: Taking a suitable projection could reduce the dose rate delivered to the angiography team. Further studies should be conducted about the effect of different projections with the same clinical use on dose distribution in coronary angiography to provide the best working conditions for physicians and staff.

Keywords:

Angiography , Radiation Dosages , Radiation dosimeter , Fluoroscopy