Globus pallidus internus versus subthalamic nucleus deep brain stimulation for isolated dystonia: A 3‐year follow‐up

Abstract

Background and purpose Bilateral deep brain stimulation (DBS) surgery targeting the globus pallidus internus (GPi) or the subthalamic nucleus (STN) is widely used in medication‐refractory dystonia. However, evidence regarding target selection considering various symptoms remains limited. This study aimed to compare the effectiveness of these two targets in patients with isolated dystonia. Methods This retrospective study evaluated 71 consecutive patients (GPi‐DBS group, n = 32; STN‐DBS group, n = 39) with isolated dystonia. Burke–Fahn–Marsden Dystonia Rating Scale scores and quality of life were evaluated preoperatively and at 1, 6, 12, and 36 months postoperatively. Cognition and mental status were assessed preoperatively and at 36 months postoperatively. Results Targeting the STN (STN‐DBS) yielded effects within 1 month (65% vs. 44%; p = 0.0076) and was superior at 1 year (70% vs. 51%; p = 0.0112) and 3 years (74% vs. 59%; p = 0.0138). For individual symptoms, STN‐DBS was preferable for eye involvement (81% vs. 56%; p = 0.0255), whereas targeting the GPi (GPi‐DBS) was better for axis symptoms, especially for the trunk (82% vs. 94%; p = 0.015). STN‐DBS was also favorable for generalized dystonia at 36‐month follow‐up (p = 0.04) and required less electrical energy (p < 0.0001). Disability, quality of life, and depression and anxiety measures were also improved. Neither target influenced cognition. Conclusions We demonstrated that the GPi and STN are safe and effective targets for isolated dystonia. The STN has the benefits of fast action and low battery consumption, and is superior for ocular dystonia and generalized dystonia, while the GPi is better for trunk involvement. These findings may offer guidance for future DBS target selection for different types of dystonia.

Architecture of the subthalamic nucleus

“…Comparative reports of dystonia cases found that targeting of either STN or GP interna (GPi) is effective for dystonia. However, STN-DBS was superior for generalized dystonia and GPi-DBS was effective for truncal dystonia 27,28 . A comparison of adverse impact between brain regions indicated that targeting the STN relatively worsened the condition of apathy compared to GPi-DBS 29 .…”