Thalamic stimulation alleviates levodopa-resistant rigidity in a patient with non-Parkinson’s disease parkinsonian syndrome

Abstract

Deep brain stimulation (DBS) to the thalamic ventrointermediate nucleus (Vim) is a useful treatment in patients with tremor-dominant Parkinson’s disease (PD). Efficacy to alleviate rigidity remains controversial. We report a 65-year-old right-handed man with persistent severe rigidity and bradykinesia on the right side despite daily administration of levodopa/carbidopa (600/60mg). His right-hand tremor was continuous at rest and present at action. His antiparkinsonian medications appeared ineffective and he reported difficulties with writing and eating. Repeated 123I-meta-iodobenzylguanidine myocardial scintigraphy studies demonstrated a non-PD pattern. He underwent the stereotactic implantation of a DBS electrode into the left Vim. Using contacts 1 and 2 we started continuous unipolar stimulation with a pulse generator implanted in a subclavian pocket. This improved the tremor and the rigidity and bradykinesia of his right hand. Postoperative image analysis revealed the likelihood of simultaneous stimulation of the Vim and the nucleus ventralis oralis posterior. Our findings suggest thalamic stimulation as a therapeutic option for drug-resistant rigidity (and tremor) in patients with parkinsonian syndromes ineligible for DBS targeted at the globus pallidus internus or subthalamic nucleus.