Parkinson's disease is usually discovered too late in patients for effective treatment. But now there's a new eye test that could diagnose the devastating condition much earlier. The degenerative condition causes muscle stiffness, slowness of movement, and tremors. Although there is no cure for Parkinsonâs, if the disease can be caught at its beginning stages, medications and other therapy could help control the symptoms. VOAâs Deborah Block has a report.