The Effect of Operative Field Instrument Clutter During Intraoperative Fluoroscopy on Radiation Exposure

Fluoroscopy units are routinely operated in the automatic brightness control (ABC) mode to optimize image quality. During ureteroscopy, objects may be placed within the fluoroscopy beam and the effect upon radiation exposure is unknown. The purpose of this study is to investigate the effects of equipment within the fluoroscopy beam during simulated ureteroscopy. ABC fluoroscopy of a cadaver was performed in eight clinical scenarios, including a control (no equipment), and seven groups with different equipment within the fluoroscopy beam. Equipment tested included electrocardiogram (EKG) leads, a Kelly clamp, camera and light cords (straight and coiled configurations), flexible ureteroscope, rigid cystoscope, and the lateral table support beam. Ten 145-second fluoroscopy trials were performed for each arm. The primary outcome was radiation dose (mGy) compared using the Mann-Whitney test with p < 0.05 considered significant. Compared with control (18.5 mGy), radiation exposure was significantly increased with the presence of a straight camera and light cords (19.3 mGy), Kelly clamp (19.4 mGy), coiled camera and light cords (20.2 mGy), a flexible ureteroscope (21.0 mGy), a rigid cystoscope (21.2 mGy), and when the lateral table support beam was in the path of the X-ray (25.0 mGy; a 35% increase; p < 0.007 for all). The EKG leads did not affect the radiation dose. Avoiding equipment within the fluoroscopy beam using ABC mode can reduce radiation exposure. Adjusting the table and patient position to exclude the lateral table support beam will reduce radiation exposure by 35%.