WHAT’S KNOW?
Parallel to the improvements in technology during past decades retrograde intrarenal surgery (RIRS) has become an efficient and safe option in the management of urinary system stone disease with a gradually increasing popularity. Ureteral access sheath (UAS) decreases intrapelvic pressure, helps with access for multiple instruments, and facilitates drainage and removal of the fragmented stones. Therefore UAS placement is a crucial step of RIRS. Although it has several advantages, UAS also remains a controversial tool in endourology due to the increased risk of ureteral injury.