Three-Dimensional Visualization of the Scattered Radiation Sources and Evaluation of Radiation Protection Measures in Cardiac Angiography

Physicians performing cardiac angiography are exposed to scattered radiation originating from the patient, and visualizing scattered radiation sources could help optimize radiation protection strategies. In this study, an existing scattered radiation source visualization system comprising a high-sensitivity CMOS camera, thallium-activated cesium iodide scintillator, and pinhole collimator was extended to incorporate a depth camera and employed to visualize scattered radiation sources in three dimensions under conditions simulating clinical cardiac angiography. Scattered radiation source images were captured using a patient phantom under multiple irradiation directions of a biplane angiography system, and changes in the images and dose rate reaching the system were evaluated with and without radiation protection equipment and for various ceiling-mounted radiation shielding positions. The scattered radiation source was visualized on the patient phantom surface for a 5-s exposure in three-dimensional images and was observed around the X-ray tube in one direction. Radiation protection equipment reduced both the scattered radiation source intensity and dose rate. The greatest reduction occurred when the ceiling-mounted radiation shielding was positioned near the physician. Irradiation at caudal angles caused the highest increase in scattered radiation source intensity and dose rate. These findings suggest that this system can support the optimization of radiation protection practices and education.