Objectives This study aimed to investigate the correlation between electrode location, volume of tissue activated (VTA), and clinical outcomes in patients with isolated generalized dystonia (IGD) undergoing deep brain stimulation (DBS) of the globus pallidus internus (GPi), and to identify predictors of treatment efficacy. Methods A total of 17 IGD patients who received bilateral GPi-DBS at Beijing Tiantan Hospital from January 2016 to December 2021 and had complete follow-up data were enrolled. The follow-up duration ranged from 12 to 60 months. Preoperative 3.0T magnetic resonance imaging (MRI) and postoperative computed tomography (CT) were used for electrode localization. Clinical efficacy was evaluated using the Burke–Fahn–Marsden dystonia rating scale (BFMDRS), including the motor subscale (BFMDRS-M) and disability subscale (BFMDRS-D). Additionally, the Hamilton anxiety scale (HAMA), Hamilton depression scale (HAMD), montreal cognitive assessment (MOCA), and mini-mental state examination (MMSE) were used to assess anxiety, depression, and cognitive function. Demographic, clinical, psychological, and cognitive variables were included in statistical analyses. Results Results showed that postoperative BFMDRS-M and BFMDRS-D scores were significantly lower than preoperative scores (both P 0.001), while no significant changes were observed in HAMA, HAMD, MOCA, or MMSE scores. In the Montreal Neurological Institute (MNI) space, the Z -axis coordinates of bilateral active electrode contacts were significantly correlated with the improvement rate of BFMDRS-M (left side: P = 0.004; right side: P = 0.041), with electrode positions closer to the ventral GPi associated with better therapeutic effects. No significant correlation was found between the VTA of the entire GPi or its subregions and BFMDRS-M improvement rate (all P 0.05). Multivariate linear regression analysis identified preoperative HAMA score as an independent predictor of poor motor outcomes ( P = 0.0189). Conclusions GPi-DBS significantly improves motor function in IGD patients. Precise electrode targeting of the ventral GPi and preoperative assessment and intervention for anxiety symptoms are crucial for optimizing DBS treatment outcomes. This study provides clinical evidence for target selection and efficacy prediction in DBS treatment for IGD patients.
Wu et al. (Thu,) studied this question.