Strokes are not always the dramatic medical emergency we all fear.
Many strokes are minor — though still dangerous — and are often mistaken by practitioners for less severe conditions, such as inner ear disturbances.
Researchers from Johns Hopkins University School of Medicine took note of these hard-to-diagnose episodes and conducted a study to see if special diagnostic goggles worn by patients could improve accuracy.
About 50,000 to 70,000 undiagnosed stroke victims are being treated for ear problems each year. The United States also spends about $1 billion annually on magnetic-resonance imaging and other procedures to make sure dizziness is not the aftermath of a stroke, said John Hopkins neurology professor David Newman-Toker.
Some doctors order these tests out of confusion over what the symptoms are telling them, while many others act out of caution to rule out stroke.
“You are talking about four million hospital visits a year in the United States for patients suffering vertigo,” Newman-Toker said. “Only 5 percent of those patients had suffered a stroke.”
Seeing signs of stroke
Specialists can visually administer three eye-movement tests to separate stroke sufferers from everyone else because strokes impair eye movement differently than vertigo.
They tell patients to stare at a fixed point on a wall while they move their head from side to side. It’s the tiny eye movements during the test that tell caregivers what has happened.
When performed by a qualified caregiver, this test is even better at diagnosing than rushing a patient for an immediate MRI scan. But here’s the problem: Not everyone is expert enough to reliably carry out the tests.
Newman-Toker said his team’s study suggests that goggles equipped with a high-speed webcam to record eye movements and an accelerometer to track head movements may be the solution.
The goggles, when connected to a standard laptop running special software, can produce a continuous picture of the eye.
“This takes away the need for extreme expertise or guesswork,” Newman-Toker said.
The goggles resemble the kind used for swimming, and Newman-Toker allows that they do look dorky. They’re also expensive — upwards of several thousands of dollars in Europe and $18,000 in the United States because of a lack of competition among manufacturers.
Patient outcomes could improve
But Newman-Toker says the goggles could be easily used to prevent misdiagnosis of as many as 100,000 strokes a year, leading to earlier stroke diagnosis and more efficient treatment decisions for patients with dizziness.
He is optimistic that the goggle test can evolve onto smaller platforms and expand into more roles, such as helping doctors diagnose concussions.
A mobile version is being looked at, but there is a fair bit of complexity involved in transferring the goggle’s capabilities to a smartphone.
A product along the lines of Google Glass seems a natural avenue to explore, he said.
“No doubt, the technology for accomplishing this test could end up being much more ubiquitous than what we have today,” he said.
Jim Nash is an award-winning business, tech and science journalist whose work has appeared in The New York Times, The Economist Group and Scientific American.Tags: Gadgets & Devices,Healthcare