Outcome after stereotactic thalamotomy for parkinsonian, essential, and other types of tremor.

A better understanding of the mechanisms underlying movement disorders, coupled with refinements in surgical technique, has led to a resurgence of interest in the surgical treatment of patients with tremor. We retrospectively analyzed the outcomes of 60 patients (62 patient sides) with medically intractable tremor who underwent stereotactic thalamotomy. Of these 60 patients, 42 had Parkinson's disease (of whom 2 patients underwent bilateral surgery for a total of 44 patient sides), 6 had essential tremor, 6 had cerebellar tremor, and 6 had post-traumatic tremor. The patients received follow-up for as long as 13 years (mean, 53.4 mo) after their operations. At the most recent follow-up visit, 86% of the patients with Parkinson's disease, 83% of the patients with essential tremor, 67% of the patients with cerebellar tremor, and 50% of the patients with post-traumatic tremor had cessation of or moderate-to-marked improvement in their contralateral tremor, with a concomitant improvement in function. The mean daily dose of levodopa for those patients preoperatively taking levodopa (n = 35) was reduced by approximately 156 mg at a mean of 53.4 months after thalamotomy. Immediate postoperative complications were common, occurring in 58% of patients. The most common complications were contralateral weakness (34%), dysarthria (29%), and confusion (23%). These complications generally resolved rapidly during the postoperative period.