Defining a national reference level for intraoperative radiation exposure in urological procedures: FLASH, a retrospective multicentre UK study

OBJECTIVES To define reference levels for intraoperative radiation during stent insertion, ureteroscopy (URS), and percutaneous nephrolithotomy (PCNL); to identify variation in radiation exposure between individual hospitals across the UK, between low- and high-volume PCNL centres, and between grade of lead surgeon. PATIENTS/SUBJECTS AND METHODS In all, 3651 patients were identified retrospectively across 12 UK hospitals over a 1-year period. Radiation exposure was defined in terms of total fluoroscopy time (FT) and dose area product (DAP). The 75th percentiles of median values for each hospital were used to define reference levels for each procedure. RESULTS Reference levels: ureteric stent insertion/replacement (DAP, 2.3 Gy/cm2 ; FT, 49 s); URS (DAP, 2.8 Gy/cm2 ; FT, 57 s); PCNL (DAP, 24.1 Gy/cm2 ; FT, 431 s). Significant variations in the median DAP and FT were identified between individual centres for all procedures (P 50 cases/annum), at a median DAP of 15.0 Gy/cm2 vs 4.2 Gy/cm2 (P