A magnetic hydrogel for the efficient retrieval of kidney stone fragments during ureteroscopy

Only 60-75% of conventional kidney stone surgeries achieve complete stone-free status. Up to 30% of patients with residual fragments <2mm in size experience subsequent stone-related complications. Here we demonstrate a stone retrieval technology in which fragments are rendered magnetizable with a magnetic hydrogel so that they can be easily retrieved with a simple magnetic tool. The magnetic hydrogel facilitates robust in vitro capture of stone fragments of clinically relevant sizes and compositions. The hydrogel components exhibit no cytotoxicity in cell culture and only superficial effects on ex vivo human urothelium and in vivo mouse bladders. Furthermore, the hydrogel demonstrates antimicrobial activity against common uropathogens on par with that of common antibiotics. By enabling the efficient retrieval of kidney stone fragments, our method can lead to improved stone-free rates and patient outcomes. The success of surgical kidney stone removal is limited by the ability to efficiently retrieve stone fragments, resulting in incomplete stone clearance and subsequent morbidity. Here, the authors show the efficacy and biocompatibility of a magnetic hydrogel that selectively coats human kidney stone fragments in vitro allowing their total extraction using a magnetic wire.

Automated summary

The researchers demonstrate a magnetic hydrogel that selectively coats kidney stone fragments for easy retrieval. The hydrogel shows good biocompatibility and antimicrobial activity, leading to improved stone clearance rates and patient outcomes.