Retrograde intrarenal surgery in lateral position for lower pole stone: an initial experience from Single Academic Hospital.

Retrograde intrarenal surgery (RIRS) was generally challenging in management of lower pole stone (LPS) since the unfavorable anatomy. Theoretically, LPS was prone to fall out and down to renal pelvis when patients turned to lateral position, thus to facilitate lithotripsy. The aim of the present study was to report our initial experience of RIRS in lateral position for LPS. From January 2020 to February 2021, 21 patients with LPS received RIRS in lateral position. The intraoperative finding, operation time, complications and stone-free rate (SFR) were recorded and analyzed. The mean stone size was 16.7 ± 2.4 mm, multiple stones in lower pole were noted in 38.1% (8/21) cases. The mean infundibular-pelvic angle (IPA) was 35.2 ± 6.9°, IPA less than 30° was noted in six cases (28.6%, 6/21). Mean operation time was 43.5 ± 6.3 min. Obvious stone fragments dropping from the lower calyx to renal pelvis during the lithotripsy were noted in 17 cases (81.0%). Only one case (4.8%) suffered postoperative fever (Clavien I), no severe complication (> Clavien II) was noted. Hospital stay was 1.1 ± 0.3 days, the SFR in postoperative 1 month was 85.7%. LPS was prone to fall out and down to renal pelvis when patients in lateral position, thus to facilitate the lithotripsy. RIRS in lateral position was feasible for the management of LPS; however, RCT with large sample was required to certify our initial finding.