Every 40 seconds, someone in the US suffers a stroke according to the CDC. Someone in the U.S. dies of a stroke every 4 minutes. A patient’s chance of full recovery from a stroke depends on how quickly treatment begins: the faster the better. Statistically, patients who get to an emergency room within three hours of the onset of the stroke have less disability after three months than those who don’t arrive within the time window.

Unfortunately, because the two major causes of stroke involve opposite problems, healthcare professionals can’t begin treatment until they know which type of stroke occurred. Ischemic stroke (too little blood to the brain) accounts for about 85% of strokes. Hemorrhagic strokes (too much blood to the brain) are much less frequent. There is an established successful treatment for ischemic stroke, but playing the odds and treating someone for ischemic stroke by increasing blood flow can be fatal if the individual has suffered a hemorrhagic stroke.

A group of scientists and researchers from China’s Army Medical University and the China Academy of Engineering Physics developed a hybrid mobile device to differentiate strokes in the field. The device combines two types of near-infrared spectroscopy to monitor a stroke victim’s hemoglobin concentration, tissue oxygen saturation, and blood flow. Because the device is sensitive to abnormal hemodynamic changes in the brain, the team believes it has significant potential for on-site differential diagnosis with stroke victims. Conventional medical testing following a stroke includes neurological exams and imaging to rule out hemorrhagic stroke. Mobile stroke units using X-ray computed tomography are speeding the traditional diagnostic time in Germany and the U.S., according to the Chinese research team, but the mobile units are large and expensive. The scientists combine diffuse correlation spectroscopy (DCS) and near-infrared diffuse optical spectroscopy in the single, hybrid device. The research team states the hybrid device is compact, inexpensive, and easy to manufacture.

Results of the team’s preliminary testing were published in the journal AIP Advances. Initial tests showed the device can measure total hemoglobin, oxygen saturation, and tissue blood flow. The research team is currently working on improving device sensitivity. If hybrid near-infrared spectroscopy for hemodynamic testing clears further development goals and clinical-testing, devices that use the technology could potentially aid emergency response personnel in stroke diagnosis in the field. Even if treatment can’t start until the patient reaches a hospital, arriving with the right diagnosis would speed the treatment.