Low-Dose Fluoroscopy Technique Drastically Decreases Patient Radiation Exposure during Percutaneous Nephrolithotomy

Abstract

IntroductionFluoroscopy is essential in percutaneous nephrolithotomy (PCNL) but exposes patients and operating room staff to radiation. We investigated whether a low-dose (LD) protocol could reduce radiation exposure during fluoroscopy-guided access without compromising clinical outcomes.MethodsPatients undergoing PCNL with fluoroscopy-guided access at a tertiary care stone center between January 2019 to July 2021 were identified. Prior to September 3, 2020, the Philips Veradius C-arm’s default settings were used: standard per-frame dose, 15 pulses per second (PPS) frame rate. After this date, a low-dose protocol was used: reduced per-frame dose, reduced frame rate of 8 PPS for needle puncture and 4 PPS for all other steps. Clinical and radiographical data were retrospectively collected. The primary outcome was cumulative radiation dose. Secondary outcomes were stone-free status (SFS; defined as no fragments ³2mm) and complications. Multivariate regression analysis was performed.Results100 patients were identified; 31 were in the LD group. The LD cohort was exposed to a significantly lower mean cumulative radiation dose of 11.68 mGy compared to 48.88 mGy (p<0.0001). There were no differences in operative time, fluoroscopy time, stone burden, SFS or complications. In a multivariable regression model adjusting for several variables, LD protocol was associated with lower radiation dose while skin-to-calyx-distance (STCD) was positively associated with cumulative radiation dose. Higher preoperative stone burden was associated with longer operative time (p=0.0001) and lower odds of postoperative SFS (odds ratio=0.959, p=0.0007).ConclusionsLow-dose fluoroscopy and decreased frame rate during PCNL decreased radiation exposure four-fold without affecting SFS or complication rates.