Flexible ureteroscopy in Chinese air force pilots with renal calculi: a cohort study at a single medical centre.

ABSTRACT

INTRODUCTION: Renal calculi are the predominant urological ailment in air force pilots. Flexible ureteroscopy (FURS) constitutes a valuable approach for renal calculi treatment. This study presents a decade-long exploration of using FURS for renal calculi treatment in air force pilots. Additionally, it investigates the safety and feasibility of granting waiver flights to pilots with renal parenchyma calcification. METHODS: From December 2009 to December 2019, a retrospective review was conducted on Chinese air force pilots undergoing treatment for renal calculi. Among the pilots assessed, a total of 71 individuals underwent FURS. Endoscopic methodology involved the insertion of a flexible ureteroscope into the ureter and renal pelvis, guided by a safety wire. Stone fragmentation was achieved using a holmium laser fibre, followed by extraction using a soft stone basket. Postoperative non-enhanced CT (NECT) scans was used to confirm stone clearance. Furthermore, clinical diagnoses were classified based on endoscopic findings and postoperative NECT results. All data were presented as mean (SD) or median (minimum-maximum) for continuous variables and frequency counts and percentages for categorical variables. RESULTS: FURS identified free kidney stones in 60 cases among all patients. The remaining 11 cases, without free stones detected during ureteroscopy, exhibited persistent high-density spots on postoperative NECT. Of the 60 cases with stones, renal calculi were successfully cleared in 30 pilots, while the remaining 30 exhibited persistent high-density spots on NECT postsurgery. Pilots with completely cleared free stones were deemed fit for flight. Pilots with diagnosed renal parenchyma calcification were granted permission to fly under waivers following a meticulous evaluation. CONCLUSIONS: FURS could not only effectively eliminate renal calculi but also accurately diagnose renal parenchyma calcification, facilitating a prompt return to flight for pilots. A protocol for managing pilot renal calculi, informed by FURS and our experience, is proposed.