Belt that warns of epileptic seizures
16 May 2013
Rice University students have created a belt that monitors signs of epileptic seizures, by detecting increased electrical conductance in the skin and changes in respiration rate, both signs that a seizure is underway. Though children or adults can wear the belt, the students designed it with kids in mind. They want parents to be aware of when a child is having a seizure, especially during the night.
The SMART (Seizure Monitoring and Response Transducer) belt has two silver / silver chloride electrodes, like those used in lie detectors, positioned on the torso. They sense electrical conductivity. The belt has another sensor that monitors breathing. The sensors are attached to a removable electronic module that acquires and transmits the signals. When the sensors show signs of a seizure, the transmitter sends data via Bluetooth to either a computer or smartphone.
''Our belt is targeted for ages 6 years and up,'' explains one of the developers Tiffany Varughese. ''It works best during the nighttime because there's not a lot of other stimuli, and we can definitely detect changes in the two signs.''
While an electroencephalograph (EEG) is the standard of care for seizure detection, it is expensive and can't be used 24 / 7, Varughese said. The students aimed for an inexpensive, comfortable device that could be worn around the clock under a patient's clothes and not only monitor for seizures but also compile a record of seizure occurrences that would be of value to their doctors, she said.
The students said testing has not been performed on people with epilepsy, but their own tests on healthy volunteers, as approved by Rice's Institutional Review Board (IRB), were promising.
To gather data, volunteers were asked to hyperventilate or they were startled by a loud noise, both of which prompt a ''fight-or-flight'' response similar to what a person with epilepsy experiences during a seizure.
The students said bed-vibration sensors are often used to detect convulsions that occur in 20 per cent of epileptic seizures, but they are prone to false positives. ''You don't want parents waking up too frequently, or they won't use the device,'' Varughese said.
''The main goal of our project was to build the sensors and demonstrate that they work, and show they have the potential to detect seizures,'' says Charles Park, another student involved in the development said.
While it does not stop a seizure in progress, such an early warning device will help parents keep their children safe, Varughese added. ''Having someone there to make sure the person is stable is the most important thing,'' she said.
