An in vivo MEMS sensor system for percutaneous measurement of urinary bladder

Abstract

Abstract-An in vivo sensor system for direct measurement of pressure in the human urinary bladder is developed. The core component in the system is a small-sized and highly sensitive piezoresistive MEMS pressure sensor element integrated in a sensor catheter. The sensor catheter is wired to an external module for biasing, sampling, conversion and storage of sensor measurements. Our solution provides a target sensor placed directly into the urinary bladder and a reference sensor placed outside the bladder wall through a suprapubic and minimally invasive technique. Physiological recordings through natural filling and emptying cycles of the bladder are achievable. The case report from the first 17-hours investigation in a patient is presented in this paper. It reveals that the procedure was successful and no complications occurred. The patient expressed good experience during the participation. A functionality test shows that the percutaneous pressure sensor system responds immediately to external pressure stimuli.

Measurement of Urinary Bladder Pressure: A Comparison of Methods

“…The MEMS-based system has been applied in a suprapubic approach for cystometry ( Figure 4 ). The solution is not yet commercially available, but a clinical trial on a sample of convenience is currently carried out [ 9 ].…”

“…Through a multidisciplinary approach, SINTEF Digital and Sunnaas Rehabilitation Hospital have over the past five years developed a new in-target organ pressure sensor system for cystometry [ 9 , 10 ]. The new sensor system is based on Micro Electro Mechanical Systems (MEMS) technology and allows for a suprapubic application of sensors in an ambulatory patient.…”

Ambulatory urodynamic monitoring: state of the art and future directions

“…As the sensor-equipped end of the catheter is in the lumen, vesical pressure is measured directly (similar to intravesical devices). Transdetrusor devices can be implanted surgically through the bladder 51,52 (FIG. 2c) or with a percutaneous approach (FIG.…”

“…The transdetrusor approach has the advantage of separating the pressure sensor element from the larger power supply and data processing unit 51,52 . Thus, the element protruding into the bladder lumen is only 4-14 Fr in diameter.…”

“…An assumption underlying the clinical utility of all but one of these catheter-free pressure monitoring devices is that intravesical pressure alone is sufficient to characterize bladder function. The only device to also measure abdominal pressure was a transdetrusor device that used sensors tunnelled into the bladder and peritoneal cavity 51 . This approach closely mimics the functionality of catheter-based AUM, but it poses an increased risk of complications (such as infections) owing to the need for two transcutaneous wires and peritoneal access.…”