Stereotactic thalamotomy for medically intractable essential tremor.

Objective surgical symptomatic outcome of ventrolateral (VL) thalamotomy specifically for essential tremor is uncommonly reported and functional outcome has not been investigated previously. In the present series, 7 patients underwent unilateral and 1 patient staged bilateral VL thalamotomies for disabling medically refractory essential tremor. At follow-up examination (mean 17.3 months, range 1-50 months), all patients enjoyed complete ablation or significant amelioration of the targeted tremor. Disability as determined by a modified form of an established rating scale for tremor was reduced from moderate (57%) or severe (43%) to absent (86%) or mild (14%). Interestingly, voice tremor was ablated or significantly improved in 71.4% of patients with preoperative voice tremor.