Irazoqui received the funding for a two-year project in partnership with Thelma Lovick of the University of Bristol. Irazoqui and Lovick lead a team that is creating an implantable device, coupled wirelessly with a bladder pressure sensor and mobile phone application, to assist in bladder control.

One-quarter to one-third of men and women in the U.S. suffer from urinary incontinence, according to the Urology Care Foundation of the American Urological Association. Aging, pregnancy, prostate problems and obesity increase the risk for incontinence, which is defined as a leaking of urine that one cannot control.

‘Electroceutical’ treatment

The bladder-control device is among a trio of “electroceutical” devices Irazoqui is pursuing as an alternative treatment to pharmaceuticals. The implantable devices use electrical stimulation of nerve fibers to relieve symptoms of urinary incontinence, digestion problems and post-traumatic stress disorder. The other two projects are funded by the National Institutes of Health and the Defense Advanced Research Projects Agency, respectively.

“We are creating implantable devices that deliver electrical therapies that reset faulty nerve wiring,” says Irazoqui, who also is the director of Purdue’s Center for Implantable Devices (a Purdue College of Engineering Preeminent Team) and a professor of electrical and computer engineering. “The tiny devices provide a targeted therapy that precisely regulates bodily functions with minimal side effects.”

The implanted devices, called “bionodes,” can be paired with monitors that measure the body’s response and adjust treatment accordingly.

“The devices are fully automatic, but a physician also can modify them to optimize a patient’s treatment,” he says.

The bladder-control bionode uses a small electric current to block the pelvic nerve and prevent voiding of the bladder. It is coupled with a pressure sensor implanted in the bladder wall. The sensor wirelessly communicates with the bionode to trigger the nerve stimulation at a bladder pressure that would otherwise initiate urination.

Wireless communication

The bionode also wirelessly communicates with a mobile phone application that allows the patient to turn off the stimulation, removing the block on the pelvic nerve, when he or she is ready to go to the bathroom.

Irazoqui created a power source to replace the need for a battery in the devices. The power source can be charged by a resonant magnetic field generated by an external device. The charging device could be placed on a bedside table — to charge the electroceutical while a patient sleeps — or could be worn to charge the device continuously, Irazoqui says.

The power source does not need to be replaced, which eliminates the need for battery-replacement surgeries. It also allowed Irazoqui and his team to shrink the size of the bionodes to 3.5 millimeters by 3.8 millimeters in size.

“We have eliminated the bulk of these devices, and they now could fit on the face of a penny,” he says. “This allows the initial implant surgery to be less invasive, and potentially faster and safer.”

An evaluation in an animal model showed the resonant magnetic field could be picked up by the power source through 30 centimeters of tissue, he says.

“Previously, this method of power supply would not work with a device implanted beyond a depth of several millimeters,” Irazoqui says. “That shallow depth greatly limited where a bionode could be implanted and what it could treat. This advance means the device could be placed nearly anywhere it is needed within a patient.”

The devices will require additional testing and approval from the Food and Drug Administration before they could be made available to patients.

“This is the result of 11 years of many people working in the Purdue Center for Implantable Devices,” Irazoqui says.