Wireless Device Developed to Monitor Kidney Pressure in Stent Patients

A research team from the University of British Columbia has published a study on a new wireless device designed to monitor pressure in the kidneys of patients with ureteral stents. The device, named UroSleeve, is a modular sleeve that fits over standard stents without changing their design. Initial testing of the concept was performed ex vivo, as detailed in the 2026 study published in Microsystems & Nanoengineering.

The modular add-on platform could enable continuous, non-invasive monitoring of kidney pressure, aiming for earlier detection of stent obstruction.

About the Device and Study

The study, "Ureteral stent sleeve for early detection of hydronephrosis" (DOI: 10.1038/s41378-026-01224-1), describes the UroSleeve as an add-on platform. It integrates a flexible spiral antenna with a microfabricated capacitive pressure sensor to form a passive LC tank circuit, which requires no battery.

The system wirelessly transmits data via near-field inductive coupling to an external antenna. The sensor uses a specialized Tesla-valve-enabled touch-mode design, which the researchers report was developed to generate stronger signals than conventional sensors.

Ex Vivo Testing and Results

The team tested the concept using a swine kidney and ureter model. They simulated hydronephrosis—kidney swelling from urine buildup—by increasing fluid pressure in the renal pelvis.

The wireless system tracked pressure rises by detecting downward shifts in the device's resonant frequency. Key test results included:

• A baseline phase-dip frequency of 15.234 MHz at a pressure of 8.5 mmHg.
• A reported sensitivity of −5.3 ± 0.74 kHz/mmHg over a tested pressure range up to 56 mmHg.

A post-test inspection noted visible distension of the ureter and renal capsule, changes the researchers stated were consistent with hydronephrosis.

Clinical Need and Potential Advantages

Ureteral stents are commonly used to relieve urinary obstruction but can themselves become blocked. Current clinical practice relies on intermittent imaging like X-rays, CT scans, or ultrasound to monitor stent function.

The researchers suggest their sleeve approach has potential advantages over earlier "smart-stent" concepts that required direct modification of the stent. The add-on design could ease adaptation to various commercial stents and simplify manufacturing and regulatory processes.

Next Steps for Development

The paper identifies several required steps before clinical use. The researchers indicate that in vivo studies are necessary to validate performance under real physiological conditions.

Future work outlined includes:

• Long-term reliability testing.
• Biocompatibility assessments.
• Development of improved readout strategies.
• Calibration for real-world clinical use.

The technology's stated goal is to allow for earlier detection of stent blockage, help guide the timing of stent exchanges, and reduce dependence on episodic imaging.