One of the first recipients of the Vocare Bladder System by NeuroControl, Kari Krumwiede, mother of four, speaks highly of the device. "The worst part of having a spinal cord injury is the whole bathroom thing. Now that I have the implant I have more time to live life."
This FES system provides individuals with paraplegia control over their bladder and bowel. It operates on a similar principle as the Freehand, however, a patient must undergo spinal surgery to have electrodes attached to the sacral root nerve in the spine--the nerve that regulates the bladder and bowels.
"Walking and hand movement is impressive, but this is the real aspect of spinal cord injury that limits a person," says Geoffrey Thrope, vice president of NeuroControl. "This is a significant issue but one that people don't talk about because society deems it inappropriate. But a person is brought back to a state of infancy. The last time anyone had to worry about this was when they were 18 months old."
Currently, people use a catheter with a digital system, requiring two to three hours per discharge. For a woman, this can be even more difficult. The Vocare requires only 30 minutes a day and the patient decides when he or she needs to use it.
A patient has a silicon-based pacemaker-type stimulator surgically implanted under the skin of the chest or abdomen (see figure). The device sends electrical signals through electrodes to the spinal nerve that lead to the bladder and bowel. These signals cause the muscles of the bladder and urethral sphincter to contract. After the bladder contracts in response to the electrical stimulus, the sphincter muscles relax, allowing the bladder to empty.
The implant is controlled with an external transmitter the size of a hand-held cassette player. The unit consists of a microprocessor and a small transmitter antenna. A person places the antenna over the implant when he or she wishes to stimulate the bladder or bowel. Radio frequency signals travel through the skin to trigger the electrical signal. The transmitter, powered by rechargeable batteries, can be stored and brought out as needed.
Thrope and other engineers at NeuroControl based the Vocare on the Finetech-Brindley Bladder Controller, originally developed by British scientist Giles Brindley. The device, implanted in more than 1,500 Europeans, has been available in Europe for the last 15 years. NeuroControl hopes to have FDA approval in the States by next year.