Due to problems with the nerves, brain or spinal cord, millions of patients no longer feel the bladder, do not know when it is full, and urgently need to empty it.
Researchers at Northwestern University have developed a soft, flexible, battery-free implant that they can attach to the bladder wall for these patients. It consists of ultra-soft, ultra-thin, stretchable manometers placed around the outside of the bladder, without imposing mechanical constraints on its normal filling and emptying behaviour. The sensors work together to measure tension in the bladder. The fuller the bladder is, the more it expands. The emptyer it is, the more elasticity it loses.
Built-in Bluetooth technology allows the implant to transmit information about these different levels of distension wirelessly and in real-time to an app on a smartphone or tablet so users can continually monitor bladder filling.
The new device is the first example of a bioelectronic sensor that allows continuous monitoring of bladder function over a long period of time. This could be a major advance for people whose bladder nerves have been temporarily or permanently damaged by surgery or whose bladder function has been temporarily or permanently affected by conditions such as spina bifida, bladder cancer, or paralysis.
It can also enable doctors to monitor their patients remotely and continuously and make more informed – and faster – treatment decisions. If left untreated, severe bladder problems can lead to routine infections, urinary tract problems, and eventually to kidney damage that affects the entire body. Patients' recovery after bladder surgery can also be monitored remotely.
Depending on the application, researchers can design the technology so that it remains in the body permanently or can be removed without problems after the patient has fully recovered.
The system has already been tested on small laboratory animals and non-human primates. The researchers showed that the sensors work and that they are sensitive enough to detect the electrical voltage of very small amounts of urine.
