Renal ablation by histotripsy--does it spare the collecting system?

Area of Science:

• Nephrology
• Medical Devices
• Ultrasound Technology

Background:

• Histotripsy, a non-thermal mechanical tissue fractionation method, has shown feasibility in vivo.
• Understanding histotripsy's effects on diverse kidney tissues is crucial for its clinical application.

Purpose of the Study:

• To investigate the bio-effects of histotripsy on different porcine kidney tissue types in vitro.
• To assess the differential impact of histotripsy on renal cortex, medulla, and collecting system.

Main Methods:

• Utilized an 18-element focused annular array ultrasound system for histotripsy treatments.
• Treated 5 in vitro porcine kidneys, targeting cortical and corticomedullary regions.
• Evaluated collecting system integrity using methylene blue infusion and assessed tissue damage via gross and histological analysis.

Main Results:

• Histotripsy caused distinct tissue defects in the targeted renal cortex.
• Fractionation occurred in the cortex, with intermediate damage in the medulla.
• Minimal damage was observed in the renal collecting system after treatment.

Conclusions:

• Histotripsy exhibits a differential treatment effect between renal cortex and collecting system.
• The renal collecting system's architecture remained largely intact post-histotripsy.
• This selective bio-effect may guide future ablative treatments for renal pathologies.