Levodopa Effective Parkinsonism Associated with Aqueductal Stenosis：a case report and review of the literature

　A case of aqueductal stenosis（AS）associated with marked parkinsonism is described．A ventriculoperi-toneal（V-P）shunt was performed in an 18-year-old female because of hydrocephalus associated with non-neoplastic aqueductal stenosis．The patient developed acute parkinsonism with Parinaud's sign after theshunt revision．

　She had a marked response to levodopa and the parkinsonism improved．Subsequently, levodopa therapywas gradually discontinued without any manifestation of parkinsonism．

The pathophysiology of this type of parkinsonism probably involved presynaptic dopaminergic dysfunc-tion. However, the etiology of this complication has not been confirmed.