Advances in fragment removal devices in ureteroscopy: up-to-date review

The development of laser lithotripsy for flexible ureteroscopy (fURS) has improved access and the ability to fragment renal stones. A common challenge for endourologists is managing the residual fragments (RF) of these stones. These RFs are associated with higher complication rates and the need for reinterventions and could serve as a focus for future stone formation. We aim to summarize recent technological advancements that increase the likelihood of removing more RFs and ultimately achieving stone-free status (SFS).

New technologies expand upon existing devices or create novel techniques, improving efficiency and increasing the volume of RF that can be extracted. Improvements to stone-grabbing baskets enable more controlled passes, reducing damage and complications. The flexible and navigable suction ureteric access sheath (FANS) builds on the traditional ureteral access sheath (UAS) by offering greater manoeuvrability and RF extraction from difficult anatomical locations. The development of urothelial-safe hydrogels provides an effective way to group and remove fragments. Additionally, magnetic hydrogels show promise for extracting tiny particles from hidden renal structures, advancing toward an ideal SFS. The Spinner-Induced Synergistic Circulation and Spiral Flow device also shows potential for rapidly removing numerous fragments.

Novel technological advancements build upon existing technologies or develop new methods of maximizing RF extraction while maintaining the balance of suction, irrigation, intrarenal pressure, and temperature - the Quadrifecta of retrograde intrarenal surgery (RIRS).