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

Abstract

Abstract Surgical management of stone disease aims for complete clearance, yet only 60–75% of ureteroscopic laser lithotripsy treatments achieve complete stone-free status. Up to 30% patients with residual fragments < 2 mm in size experience stone-related complications. We demonstrate a method of stone fragment retrieval in which fragments are coated with a magnetic hydrogel and retrieved en masse with a magnetic guidewire. The magnetic hydrogel facilitated robust in vitro capture of stone fragments up to 4 mm in size across a wide range of stone compositions. The components exhibited no cytotoxicity in cell culture and only superficial effects on the urothelium in ex vivo human urothelium and in vivo mouse bladders. Furthermore, the hydrogel demonstrated antimicrobial activity against common uropathogens on par with that of common antibiotics. By enabling the efficient retrieval of kidney stone fragments, our method could lead to improved stone-free rates and patient outcomes.