Functional outcomes after gamma knife thalamotomy for essential tremor andMS-related tremor

Twelve patients with a median age of 75 years underwent gamma knife thalamo tomy for essential tremor (ET) (n = 9) or MS-related tremor (n = 3). All 11 evaluable patients noted improvement in action tremor. Six of eight ET pat ients had complete tremor arrest, and the violent action tremor in all thre e patients with MS was improved. One patient developed transient arm weakne ss. Stereotactic radiosurgery for ET and MS-related tremor is safe and effe ctive for patients who may be poor candidates for other procedures.