Novel Technologies to Improve Bladder Surgery and Monitoring

In cases where bladder capacity needs to be increased, bladder augmentation is often performed using a segment of the patient's bowel tissue. This procedure is also common among individuals with spinal injuries or congenital conditions like spina bifida or bladder exstrophy. Although bladder augmentation can significantly enhance a patient's quality of life, it carries a high risk of complications, necessitating extensive postoperative monitoring. To address these challenges, a team at Northwestern University (Evanston, IL, USA), supported by the National Institutes of Health (NIH, Bethesda, MD, USA), is exploring two innovative technologies—one to improve bladder function through a cell-seeded, biodegradable construct that aids tissue regeneration, and another to enhance patient monitoring via an implantable bladder sensor.

Historically, bowel tissue has been the standard material for bladder augmentation despite the clinical complications arising from the physiological and anatomical differences between bowel and bladder tissues. These differences often leave patients with a dysfunctional, infection-prone, and failure-susceptible bladder. The researchers are investigating an alternative approach involving a synthetic scaffold that supports the regeneration of native bladder tissue. This scaffold, seeded with the patient’s own stem cells, supports tissue growth and eventually biodegrades, leaving behind newly formed bladder tissue. Previous attempts to create such scaffolds have not succeeded in clinical trials. For this project, the researchers used citric acid, a naturally occurring molecule, to create a scaffold with customizable properties. In their study, the team used a baboon model to compare the effects of augmenting bladders with the new scaffold versus traditional ileum grafts. Over two years, they observed significantly fewer complications such as urinary tract infections and kidney issues in the baboons implanted with the scaffold compared to those with ileum grafts. Analysis of the regenerated tissue showed that it closely resembled normal bladder tissue in its composition, unlike the predominantly muscular ileum tissue which does not mechanically match bladder tissue.

For post-operative monitoring, typically done through invasive urodynamic testing that only offers a snapshot of bladder function, the researchers developed an implantable sensor. This sensor is designed to provide continuous, remote monitoring of the bladder by transmitting data wirelessly about bladder expansion and contraction, which could potentially alert healthcare providers to complications much earlier. The sensor system includes a strain gauge, a base station with a Bluetooth chip for communication, and a helical coil wire connecting the two. When tested in a baboon model, this sensor effectively transmitted bladder function data for eight weeks, demonstrating its potential to enhance patient care by providing ongoing, real-time insights into bladder health post-surgery. Together, these advances not only promise to improve the management of bladder surgeries but also represent significant progress in regenerative medicine and bioelectronics, offering new ways to treat and monitor patients effectively.

“As biotechnologies advance, they will need to integrate more seamlessly with the human body,” said Jessica Falcone, Ph.D., a program director in the Division of Discovery Science and Technology at the National Institute of Biomedical Imaging and Bioengineering (NIBIB). “This research team has successfully navigated interfacing with the bladder without interfering with its function, bridging the fields of tissue regeneration and flexible bioelectronics. Such advances could enhance the lives of future patients requiring bladder surgery.”

Related Links:
Querrey Simpson Institute, Northwestern University
NIBIB