Endoscopic Treatment of Lower Pole Stones: is a Disposable Ureteroscope Preferable? Results of a Prospective Case-control Study

Introduction: The best option for lower pole stone management is still under debate. With the recent incorporation of disposable ureteroscopes, discussion on this topic has been renewed. The aim of the present study was to compare the results obtained with flexible disposable ureteroscopes with those obtained using reusable ureteroscopes in the treatment of inferior calyx stones.

Material And Methods: A case-control study was carried out using data registered prospectively in a database at our center. The clinical results obtained in two groups of patients were analyzed. In the first group of patients, a reusable flexible fiber-optic ureteroscope (Cobra, Richard Wolf) was used, and in the second group, a disposable flexible ureteroscope was used (Uscope 3022, Pusen Medical). The variables analyzed included: operative time, fluoroscopy time, need for postprocedure ureteral catheter, stone-free rate (fragments <1 millimeter) and complications. The results were evaluated using a Student's t test, a Mann-Whitney test and a Fisher's test.

Results: There were 31 cases with disposable ureteroscopes and 30 cases with a reusable ureteroscope. Both groups were comparable in their demographic and clinical variables. The characteristics regarding length, width and angle of the infundibulum (measured by retrograde ureteropyelography) were also comparable. There were no differences in the clinical findings with respect to the stone-free rate, need for a ureteral catheter, complications or hospital stay. Significant differences were found in the average surgery time (56.1 vs. 77 minutes; P = 0.01) and in the fluoroscopy time (66.1 vs. 83.4 seconds; P = 0.02), both favoring the use of single use ureteroscopes.

Conclusions: In this study, disposable flexible ureteroscopes have been validated as an option that is in the least equivalent to reusable ureteroscopes based on clinical results. The shorter surgical and fluoroscopy durations are possible advantages considering the high costs associated with time spent in the operating room and the need to reduce ionizing radiation.