Comparative performance of single-use flexible ureteroscopes with and without direct in-scope suction: a...

Ureteroscopy represents the primary therapeutic approach for a broad spectrum of upper urinary tract stones. The aim of this study was to compare the efficiency of various models of single-use flexible ureteroscopes, some of them with direct in-scope suction (DISS) capabilities. A retrospective study was conducted over a 16-month period, including 75 consecutive patients who underwent retrograde intrarenal surgery for renal lithiasis. Patients were allocated into three groups according to the flexible ureteroscope used: a 7.5 Fr single-use ureteroscope without suction (Group A), a 7.5 Fr single-use ureteroscope with direct in-scope suction (Group B), and a 9.2 Fr single-use ureteroscope with a 5.1 Fr working channel and direct in-scope suction (Group C). Perioperative outcomes, residual stone fragments, and subjective intrarenal visualization were evaluated and compared among groups. A total of 75 patients were included, with stones most frequently located in the renal pelvis (40.0%), followed by the inferior (30.6%), middle (21.3%), and superior calyces (8.0%). Residual stone fragments were observed in 24.0% of cases in Group A, 16.0% in Group B, and 4.0% in Group C; although these differences did not reach statistical significance (P = 0.132), a numerical trend toward improved stone clearance was noted with increasing ureteroscope caliber and the use of direct in-scope suction. Subjective intrarenal visualization differed significantly among groups, with the 5.1 Fr working-channel ureteroscope (Group C) achieving significantly higher visualization scores compared with both 7.5 Fr devices (P < 0.001). Operative time, hospitalization duration, and postoperative complication rates were comparable across groups. In this retrospective comparative analysis, single-use suction-enabled flexible ureteroscopes demonstrated safety and operative efficiency comparable to those of conventional single-use devices. Although differences in residual fragment rates did not reach statistical significance, improved stone clearance seems to correlate with increasing ureteroscope caliber and the integration of DISS. The 9.2 Fr ureteroscope with a 5.1 Fr working channel provided significantly superior intrarenal visualization, potentially facilitating more efficient lithotripsy.