The Comparison of the Efficacy and Safety of Vacuum-Assisted and Conventional Ureteral Access Sheath in Retrograde Intrarenal Surgery: A Randomized Controlled Prospective Multicenter Study

The use of ureteral access sheath (UAS) during Retrograde Intrarenal Surgery (RIRS) has been proven effective and reliable in recent years, and publications indicate that it reduces stone-free rates (SFR). Their use is also recommended in the European Urology Guidelines because it improves image quality, reduces intrarenal pressure, and shortens the operation time. For this reason, it has been routinely used in many RIRS cases. In cases where non-vacuum-assisted UAS is used, fragments during stone fragmentation remain in the kidney, and since it is not possible to remove the stones simultaneously, the image may be distorted, and the operation duration may be prolonged. All these may pave the way for postoperative infectious complications. In addition to non-vacuum-assisted UAS, new UASs with flexible ends and vacuum-assisted aspiration have been introduced in the last few years (ClearPetra). Thanks to the aspiration connected to the system, stone fragments can be removed from the body with negative pressure during stone fragmentation. Continuous circulation prevents bleeding during fragmentation and blurring of the visual field due to stone fragments. In addition, since the stone fragments pass through the edges of the sheath without breaking and are removed, a perfect field of view can be provided. Unlike the classical UAS, the tip is flexible, allowing for the safe removal of lower pole stones. Many studies in the literature compare the success and complications of RIRS in cases where conventional UAS was used and not used. In addition, there are publications related to using the newly introduced aspiration access sheath in percutaneous nephrolithotomy. In retrospective publications on using this UAS in RIRS, it has been shown that stone-free rates, operation time, hemoglobin loss, and postoperative infective complications are more successful on the 1st and 30th postoperative days compared to cases where non-vacuum-assisted UAS was used. There is no randomized controlled prospective publication on this subject. This study aims to compare the complications and stone-free rates of RIRS cases where non-vacuum-assisted UAS and new vacuum-assisted UAS were used.