Ex-Vivo Testing of Smart Ureteral Stent Toward Hydronephrosis Monitoring via Standard Stenting

This work presents a telemetric “smart” ureteral stent that offers, for the first time, compatibility with the standard stenting procedure to enable real-time sensing of ureteral obstruction and resultant kidney swelling at an early stage. This advanced ureteral stent integrates micro pressure sensors and a radiofrequency antenna to configure a resonant circuit for noninvasive kidney pressure monitoring via the indwelling stent. The stent prototype, electrically and biologically passivated by Parylene C, is tested in a harvested swine kidney-ureter model filled with artificial urine, demonstrating wireless pressure tracking with a response of 1.3 kHz/mmHg in cycled pressure variations up to 37 mmHg representing a reported average pressure rise due to chronic occlusion. The successful measurement enabled via prototype's placement into the model using today's stenting method and tools indicates potential clinical compatibility of the technology.