A Novel Distal Active Flexible Vacuum-assisted Ureteric Access Sheath in Retrograde Intrarenal Surgery

Introduction Retrograde intrarenal surgery (RIRS) is one of the primary treatments for renal stones. The ureteral access sheath (UAS) was widely used in RIRS. 1 Gauhar V. Chew B.H. Traxer O. et al. Indications, preferences, global practice patterns and outcomes in retrograde intrarenal surgery (RIRS) for renal stones in adults: results from a multicenter database of 6669 patients of the global FLEXible ureteroscopy Outcomes Registry (FLEXOR). World J Urol. 2023; 41: 567-574 Crossref PubMed Scopus (14) Google Scholar , 2 Breda A. Territo A. López-Martínez J.M. Benefits and risks of ureteral access sheaths for retrograde renal access. Curr Opin Urol. 2016; 26: 70-75 Crossref PubMed Scopus (58) Google Scholar The aim of this paper is to introduce a new UAS, the distal active flexible vacuum-assisted ureteral access sheaths (DAFV-UAS), for the renal calculus during RIRS. Case Presentation A 56-year-old female presented to the outpatient clinics of our hospital with a left renal lower calyx stone. Abdominal CT demonstrated that the left kidney's lower calyx stone size was 10.54 × 10.38 mm, and the mean Hounsfield density was 965HU. After adequate anti-infective treatment, the DAFV-UAS was used in RIRS. No perioperative complications were observed. The left renal stone had been cleared completely. Discussion The DAFV-UAS (10/12.5 Fr, 38 cm, creek, Jiangsu, China) includes a good flexibility and deformability tube at the tip, about 10 cm long. It has an active bending function, negative pressure suction function, and the function of convenient flexible ureteroscopy (f-URS) entry and exit of the ureter. 3 Qian X. Liu C. Hong S. et al. Application of suctioning ureteral access sheath during flexible ureteroscopy for renal stones decreases the risk of postoperative systemic inflammatory response syndrome. Int J Clin Pract. 2022; 20229354714 Crossref Scopus (10) Google Scholar In this case, the f-URS adopted a 7.5 Fr single-use digital f-URS. The Irrigation method was automated irrigation system, and the flow was 30 mL/min. The suction level was 0.02 mpa. With the help of DAFV-UAS, the field of view is always clean, the small gravel particles can be sucked out from the sheath gap, and the larger gravel particles are sucked out by withdrawing the scope intermittently. Conclusion DAFV-UAS is a promising new device which allows for negative pressure suction directed right at a renal stone and efficient and effective stone clearance.