The majority of strokes are caused by a blood clot in the brain which cuts off blood flow. The recommended treatment for this type of stroke is to quickly use drugs (within 90 minutes) which help to clear the blood clot. This, however, is not the only way a stroke can occur. In about one in five cases, the stroke is caused not by a blood clot, but by a burst blood vessel. In these cases, if the medication to treat the blood clot were to be administered, it would cause catastrophic bleeding in the patient, which would likely result in death. This is why it’s so important for the doctors to quickly determine the correct cause of the stroke.
Currently the only way to determine what type of stroke has taken place is to use a CT scan. While there are a few of these devices which are carried by ambulances, they are extremely expensive, and it’s not practical for every ambulance to be equipped with one. That means the patient needs to be taken to a hospital, and given a CT scan which can waste a lot of precious time in determining the cause of the stroke. There’s a new device being developed in Sweden which may one day change how quickly a stroke diagnosis can be made.
The new device, which currently is only a prototype and has been nicknamed the “StrokeFinder” by researchers, has 12 antennas arranged around the head in the shape of a helmet. One at a time, each of the antennas sends a low-powered microwave signal through the persons skull while the other 11 antennas analyze changes which have occurred as the signal has passed through the patient’s brain. By looking at the microwave patterns, the device is able to detect bleeding in the brain. The best part is the device is portable and only takes a few seconds to work.
The microwave helmet isn’t perfect, but it shows a lot of promise. The first pair of clinical trials tested 45 stroke patients, and the results from the stroke finder were compared with CT scans. The findings from these trials were published online by IEEE Transactions on Biomedical Engineering.
The trials showed the device was able to correctly identify all 19 patients out of the 45 who were suffering from cranial bleeding. While this was wonderful news, the device also gave a number of false-positives. The stroke finder indicated five patients who were suffering from blood clots might have cranial bleeding. The researchers plan to work on the algorithms to decrease the number of false-positive detections in future trials. The first trials with the device being used in ambulances are planned for this fall.
(Photo courtesy of Gunilla Brocker)