Neuropsychological and quality of life outcome after thalamic stimulation for essential tremor

Objective: To evaluate short-term effects of unilateral thalamic deep brain stimulation (DBS) on cognition, mood state, and quality of life in patient s with essential tremor (ET). Background: Unilateral thalamotomy and thalam ic DBS are effective in alleviating refractory tremor contralateral to the side of surgery. Thalamotomy can lead to cognitive morbidity, and DBS might be a preferable surgical intervention given potential avoidance or reversi bility of such morbidity. Although unilateral thalamic DBS is cognitively s afe and leads to quality of life improvement in PD, its neurobehavioral eff ects in ET are unknown. Methods: Forty patients with ET were administered a broad neuropsychological test battery, measures of mood state, and generic and disease-specific quality of life measures approximately 1 month before and 3 months after surgery (left hemisphere, 38 patients). Results: Unilat eral thalamic DBS was associated with significant improvements in tremor an d dominant-hand fine visuomotor coordination. Statistically significant but clinically modest gains were observed on tasks of visuoperceptual and cons tructional ability, visual attention, delayed word list recognition, and pr ose recall. Only lexical verbal fluency declined significantly after surger y. Patients rated themselves as less anxious after surgery, and they percei ved their quality of life as improved significantly. In particular, patient s reported improved quality of life with respect to activities of daily liv ing, stigma, emotional well-being, and communication. Conclusions: Unilater al thalamic DBS for ET is cognitively safe and associated with improvements in anxiety and quality of life in the near term and in the absence of oper ative complications. Patients were better able to carry out activities of d aily living after surgery, and they reported improvement in several psychos ocial domains of quality of life.