The neuronal basis of hyperkinetic movement disorders has long been unclear. We now test the hypothesis that changes in the firing pattern of neurons in the globus pallidus internus (GPi) are related to dyskinesias induced by low doses of apomorphine in patients with advanced Parkinson's disease (PD). During pallidotomy for advanced PD, the activity of single neurons was studied both before and...

DYSKINESIAS are the most common motor complication of drug therapy for Parkinson disease (PD). Propofol may induce dyskinesias and choreoathetoid movements in patients with PD and without PD. We describe a patient with PD who developed propofol-induced dyskinesias during bilateral subthalamic nucleus deep brain stimulator (DBS) placement for PD. Dyskinesias were effectively controlled with dexm...

BACKGROUND The effect of dopaminergic therapy on balance in Parkinson's disease (PD) remains unclear, including previous studies that excluded the effect of dyskinesias or other involuntary movements on postural sway. Additionally, medication's effects may differ between fallers and non-fallers. In this study, the authors quantify the effect of dopaminergic medication on postural balance (sway)...

OBJECTIVE In Parkinson disease (PD), long-term treatment with the dopamine precursor levodopa gradually induces involuntary "dyskinesia" movements. The neural mechanisms underlying the emergence of levodopa-induced dyskinesias in vivo are still poorly understood. Here, we applied functional magnetic resonance imaging (fMRI) to map the emergence of peak-of-dose dyskinesias in patients with PD. ...

Haloperidol was used in 12 patients in an attempt to improve l-dopa induced dyskinesias. In eight patients any improvement in dyskinesias was associated with increased Parkinsonism. In four patients the dyskinesias initially improved without clinical deterioration. Within several weeks, however, the disability due to Parkinsonism increased in these four patients as well. These observations sugg...

The objective of this study was to characterize levodopa (l-dopa)-induced dyskinesias in patients with tyrosine hydroxylase deficiency. Clinical observation was carried out on 6 patients who were diagnosed with tyrosine hydroxylase deficiency and were treated with escalating doses of l-dopa. All 6 patients showed l-dopa-induced dyskinesias of variable intensity early in the course of treatment ...

BACKGROUND Motor fluctuations and dyskinesias can cause disability and reduce quality of life for patients with Parkinson disease (PD). OBJECTIVES To evaluate factors associated with the development of motor fluctuations and dyskinesias and to assess the sequence in which they occur in individual patients. DESIGN We performed a retrospective analysis of data from a randomized clinical trial...