Visor-like device detects severe strokes in 30 seconds

A visor-like wearable device detected emergent large vessel occlusion (ELVO) with 92 percent accuracy in a study of 248 individuals, outperforming standard neurologic assessment tools based on physical examination.

Endovascular therapy (EVT) is the standard of care for ELVO within 24 hours, but good outcomes are more likely the earlier a patient is treated. Considering only about 10 percent of stroke centers are capable of performing EVT, it is crucial to accurately and quickly triage patients with severe strokes, wrote lead author Christopher P. Kellner, MD, and colleagues in the Journal of NeuroInterventional Surgery.

The volumetric impedance phase shift spectroscopy (VIPS) device (Cerebrotech Medical Systems, Pleasanton, California) is placed around a suspected stroke victim’s head and takes roughly 30 seconds to complete a scan.  

“Radio waves of different frequencies are modified differently as they pass through the tissue, depending on the type and fluid properties of the tissue, producing a unique signature for varied brain pathologies,” the researchers noted. Then, results are transmitted to a laptop via Bluetooth.

The VIPS device detected stroke with 92 percent accuracy and with a false positive rate of 7 percent. Traditional tools based on physical evaluation achieved 40 to 89 percent accuracy in identifying ELVO. All patients were later diagnosed definitively using neuroimaging.

Kellner and colleagues likened the device to portable ECGs for heart attacks; both could be easily transported in ambulances and used to triage patients in emergency cases.

“Future testing is necessary to validate this device as a diagnostic tool in specific patient populations and settings,” they wrote. “With such a high diagnostic accuracy for severe stroke, other potential settings where triage is necessary might include locations with people at a higher than usual risk for stroke, such as nursing homes, in operations with increased stroke risk such as cardiothoracic surgery or carotid endarterectomy, and settings removed from standard medical care, such as cruise ships, flights, and third world settings where neuroimaging is not readily available.”

The researchers next plan to evaluate whether the device can use machine learning algorithms to allow laypeople to discriminate between minor and severe stroke without the aid of neurologists. If this were the case, study coauthor Raymond D. Turner, MD, said he could envision the devices being kept in public spaces similar to defibrillators.

"You can find out if a patient is having a stroke, just like you can put a defibrillator on a patient to see if they're having a heart attack,” Turner said in a press release issued by the Medical University of South Carolina, where he is the chief of the Neuroscience Integrated Center for Clinical Excellence.

Cerebrotech Medical Systems, the maker of the VIPS product, funded the study.