Scatter radiation absorbed dose distribution in coronary angiography: A measurement based study

Abstract

Introduction: This study aimed to investigate the absorbed dose of scatter radiation in coronary angiography. Materials and Methods: The scatter radiation dose was measured for 20 patients at four different heights (50,100, 150 and 165 cm) from the floor. Spatial dose was measured by RTI Piranha r100b solid state dose probe at different points around the patient in actual clinical situation and with phantom. Also the measurement was repeated using a designed phantom in fluoroscopy and cine mode in PA, LLAT, LPO, RAO and RLAT projections. The dose to dose area product (DAP) conversion coefficients for each organ were calculated. 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˂0.05). It was found that the dose rate changes in fluoroscopic mode compared to cine mode are significantly different (p = 0.001). The dose rate in cine mode is approximately four times of that in fluoroscopy mode. The dose rate around the cardiologist waist could be reduced by 37 – 43 % with a displacement of 20cm away. Conclusion: Taking a suitable projection could indeed reduce the dose rate delivered to the angiography team. In this study, the effective dose rate received by the cardiologist’s eyes was higher than those reported by ICRP.