Outcome after stereotactic thalamotomy for dystonia and hemiballismus.

The outcome after single or staged stereotactic thalamotomies in 17 patients with dystonia and 2 patients with hemiballismus is reviewed. All patients were severely disabled by their movement disorders despite optimal pharmacological therapies. Eight of the patients with dystonia (47%) showed moderate improvement immediately after the procedures. Six of these eight patients maintained their improvement, and two other patients with dystonia improved significantly, during the follow-up period (mean, 37.6 mo). The long-term outcome was better in patients with secondary dystonia (50% moderately or markedly improved at a mean of 41.0 mo) than in patients with primary dystonia (43% moderately or markedly improved at a mean of 32.9 mo). Excellent control was achieved in both of the patients who underwent thalamotomies for hemiballismus.