Convergence insufficiency in idiopathic Parkinson's disease responsive to levodopa.

We report a patient with pathologically proven idiopathic Parkinson's disease (IPD) who developed diplopia secondary to convergence insufficiency during his motor "off" periods. Diplopia resolved with onset of motor benefit from levodopa. Neuro-ophthalmologic examination demonstrated convergence insufficiency during motor "off" periods that was alleviated after onset of motor benefit from levodopa. This is the first reported case of convergence insufficiency in IPD responsive to levodopa.