When people have nerve problems such as those caused by spinal injuries, they can lose the ability to feel when their bladder is full. This means that they don't know when it needs to be emptied, resulting in a build-up of pressure that can damage both the bladder and their kidneys. Now, a tiny sensor may offer a better way of assessing their condition, to see if surgery is required or if medication will suffice.
Presently, in order to observe how well the bladder is functioning, a catheter is inserted into the patient's urethra and used to fill their bladder with saline solution. This is understandably uncomfortable for the patient, plus it's claimed to provide an inaccurate picture of what's going on, as the bladder fills up much more quickly than would normally be the case.
That's why scientists at Norwegian research group SINTEF are proposing replacing the catheters with tiny pressure sensors. The current prototypes can be injected into the bladder directly through the skin, and could conceivably stay in place for months or even years, providing readings without any discomfort, and without requiring the bladder to be filled mechanically.
Patients would be able to move around normally, plus the risk of infection would reportedly be reduced. Currently readings are transmitted from the prototypes via a thin wire that extents from the senor out through the skin, although it is hoped that subsequent versions could transmit wirelessly – perhaps even to the patient's smartphone.
Next month, a clinical trial involving three spinal injury patients is scheduled to begin at Norway's Sunnaas Hospital. Down the road, plans call for trials involving 20 to 30 test subjects.
Although they're currently about to be tested in the bladder, the sensors could conceivably be used to measure pressure almost anywhere in the body.