PD4-04 USE OF FLUOROSCOPY AND POTENTIAL LONG-TERM RADIATION EFFECTS ON CATARACT FORMATION

Abstract

INTRODUCTION AND OBJECTIVES: The increased use of fluoroscopy exposes practicing urologists to frequent radiation exposure. The human eye is a highly radiosensitive part of the body and long-term exposure to radiation can initiate cataract formation. Many physicians now wear lead lined glasses for safety. We explored the radiation exposure of urologists at our institution to determine whether they are at an increased risk for cataract formation. METHODS: A retrospective review of a multi-surgeon, prospectively maintained database of fluoroscopic cases between 10/ 2013 to 10/2014 identified a total of 691 cases. The screening time, kV and mA were recorded from all cases in the operating room. The procedures were performed by different subspecialties of urology and included stent insertion, ureteroscopic lithotripsy, and percutaneous nephrolithotomy. We calculated the radiation dosimetry of urologists through the methods described by the National Council on Radiation Protection (NCRP) and extrapolated the dose exposure to determine risk of cataract formation. For the calculated dosimetry, technical specifications of the GE OEC 990 mobile C-arm unit were used. The surgeon was assumed to be standing at a distance of 75 cm with a scattering angle of 45 degrees to estimate the radiation dose to the surgeon’s eye. RESULTS: The average fluoroscopic time was 35.35 seconds per case. The average tube potential and tube current was 89.69 kV and 1.96 mA, respectively. Pediatric urologists used the least amount of fluoroscopic time, 11.86 seconds per case (p 1⁄4 0.0047). Endourology fellowship trained urologists utilized the longest time of fluoroscopy, 70.33 seconds per case (p < 0.0001), while non-endourologists utilized 27.24 seconds per case (p < 0.0001). This may be related to the complexity of the cases. The tube potential and current for endourology cases were recorded as 91.34 kV and 1.81 mA (p1⁄40.11). The total number of endourology cases over the past year was 131. Using this data, we then calculated the estimated radiation dose to the eyes for the most highly exposed urologists at our institution to be 5.64 mGy per case. For the past year, the total estimated cumulative dose would then be 738.84 mGy. CONCLUSIONS: Yearly eye exposure limits are currently defined at 150 mSv by the NCRP. Over the past year, our highest exposed urologists compiled an estimated dose of 0.5% of the annual limit. We conclude that fluoroscopy is a safe method in the urological field. With the use of newer radiation technologies and sensible radiation principles, the risk to the surgeon is diminishing.