Deep brain stimulation in the caudal zona incerta in patients with essential tremor: Effects on cognition 1 year after surgery

Abstract

OBJECTIVE The ventral intermediate nucleus (VIM) of the thalamus is currently the established target in the use of deep brain stimulation (DBS) to treat essential tremor (ET). In recent years, the caudal zona incerta (cZi), a brain target commonly used during the lesional era, has been revived as the primary target in a number of DBS studies that show evidence of the efficacy of cZi targeting in DBS treatment for controlling the symptoms of ET. The authors sought to obtain comprehensive neuropsychological data and thoroughly investigate the cognitive effects of cZi targeting in patients with ET treated with DBS. METHODS Twenty-six consecutive patients with ET who received DBS with cZi as the target at our department from December 2012 to February 2017 were included in this study. All patients were assessed using a comprehensive neuropsychological test battery covering the major cognitive domains both preoperatively and 12 months postoperatively. RESULTS The results show no major adverse effects on patient performance on the tests of cognitive function other than a slight decline of semantic verbal fluency. CONCLUSIONS This study indicates that the cZi is a safe target from a cognitive perspective in the treatment of ET with DBS.