The Many Faces of Blurry Vision in Parkinson's Disease: An Illustrative Case Series.

Ocular disorders constitute a major component of the non-motor symptoms of Parkinson's disease (PD). Blurry vision is commonly associated with PD, but often challenging to interpret. The clinical spectrum of blurred vision is broad, and finding the underlying aetiology can be challenging. An incomplete diagnosis impedes therapeutic successes. We report two persons with PD who both experienced blurry vision, but each with a different underlying pathology that called for specific ophthalmological and neurological treatments. In case 1, the blurry vision was presumably caused by strabismus and convergence insufficiency, while case 2 had blurry vision partly due to palinopsia, a higher order visual processing deficit. Adequate treatment improved vision in both cases. Neurologists should be aware of the different underlying causes of blurred vision, should master the basic therapeutic approaches, and know when to refer a patient to the ophthalmology department.