Simple Bedside test to distinguish between a Stroke and innocuous dizziness
To distinguish between a stroke and harmless dizziness is very important and difficult in general. It feels very similar but a stroke can be catastrophic!
It is important to know what is a stroke and what is not… and even in the best of hospitals, this can be difficult in the first instance.
The diagnosis of stroke in patients with severe dizziness, vomiting, difficulty walking and intolerance to head motion is difficult, Newman-Toker says. He estimates there are 4 million emergency department visits annually in the United States for dizziness or vertigo, at least half a million of which involve patients at high risk for stroke. The most common causes are benign inner ear conditions, but many emergency room doctors, Newman-Toker says, find it nearly impossible to tell the difference between the benign conditions and something more serious, such as a stroke. So they often rely on brain imaging – usually a CT scan, an expensive and inaccurate technology for this particular diagnosis.
However, experts can tell the difference by doing three “eye movement tests”.
One of those tests, known as the horizontal head impulse test, is the best predictor of stroke. To perform it, doctors or technicians ask patients to look at a target on the wall and keep their eyes on the target as doctors move the patients’ heads from side to side. But, says Newman-Toker, it requires expertise to determine whether a patient is making the fast corrective eye adjustments that would indicate a benign form of dizziness as opposed to a stroke.
Now a small device will be able to discern if the person is suffering from just dizziness or a stroke.
a small, portable device — a video-oculography machine that detects minute eye movements that are difficult for most physicians to notice. The machine includes a set of goggles, akin to swimming goggles, with a USB-connected webcam and an accelerometer in the frame. The webcam is hooked up to a laptop where a continuous picture of the eye is taken. Software interprets eye position based on movements and views of the pupil, while the accelerometer measures the speed of the movement of the head.
