Eye Exams Can be Used to Predict Stroke Risk

A study done at the University of Zurich has shown that Strokes caused by carotid artery stenosis (CAS) can be detected with a simple eye exam. The condition blocks or clogs the arteries that feed the front of the brain. It often goes undetected until after a patient starts showing signs of a stroke because the symptoms associated with CAS have not yet been identified.

There are high-tech test available that can detect the condition but they are expensive, not seen to be worth the cost and therefore not widely used. The U.S Preventive Services Task Force said in a research review that finding a simple inexpensive screening test for CAS could significantly reduce strokes and the resulting disabilities and fatalities.

The new ocular pulse amplitude (OPA) exam could be performed even during a routine eye exam. It uses a device called a dynamic contour tonometer which measures the systolic and diastolic pressure levels in the eye. It then measures the difference between the two to compute the OPA score. Because in CAS the blood flow is blocked there isnt much difference in the pressure levels, and therefore a low OPA score indicates blockage.

The study was done on 67 patients thought to have CAS. After the test was given the findings were verified using ultrasound exams and the severity of the condition was measured. Lower scores were found in those with more severe blockage.

"Our results show that ocular pulse amplitude is a reliable, safe screening test for carotid artery stenosis. We recommend further study to confirm the value of using OPA to detect and assess the severity of CAS and to define its use in stroke prevention," said lead researcher Pascal Bruno Knecht, M.D.

The Study Published in the June Issue of Opthamology

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