Correlation between brain structural features and early motor outcomes from deep brain stimulation in patients with...

Subthalamic nucleus deep brain stimulation (STN-DBS) is an effective neuromodulation therapy for patients with mid-to-late-stage Parkinson disease (PD), demonstrating significant efficacy at the group level. However, therapeutic outcomes across individual patients vary. This study investigated the correlation between brain structural characteristics and the early motor outcomes after administration of bilateral STN-DBS in patients with PD.

A total of 26 patients with PD were assessed 3-6 months after surgery according to Unified Parkinson's Disease Rating Scale Part III (UPDRS-III) score. Patients were stratified into a high-improvement group (HMI; n=19) and a low-improvement group (LMI; n=7) based on a 30% improvement rate. Structural magnetic resonance imaging (MRI) analysis methods were used to compare the two groups' gray-matter volume (GMV) and white-matter (WM) tract integrity. Least absolute shrinkage and selection operator (LASSO) regression was applied to identify potential neuroanatomical predictors of response to DBS.

All patients showed significant motor improvement (P<0.001), with a median reduction of 9.20 points in UPDRS-III score. Compared with the HMI group, the LMI group exhibited greater GMV atrophy in the bilateral middle frontal gyrus, left dorsolateral superior frontal gyrus, anterior cingulate gyrus, orbital part of the inferior frontal gyrus, medial superior frontal gyrus, posterior orbital gyrus, right globus pallidus, gyrus rectus, precuneus, and middle cingulate gyrus (P<0.05). The GMV in the bilateral supplementary motor areas (SMAs), bilateral putamen, left supracallosal anterior cingulate cortex (ACC), and left lateral geniculate body was positively correlated with the postoperative UPDRS-III score (P<0.05). Tract-based spatial statistics revealed decreased WM tract integrity in the right anterior thalamic radiation, inferior frontal-occipital fasciculus, superior longitudinal fasciculus, and forceps minor (P<0.05). Notably, although LASSO analysis identified the GMVs of the right globus pallidus, precuneus, and left supracallosal ACC as predictors of DBS response, these variables were excluded from the final model due to nonsignificant P values (P>0.05) in multivariate logistic regression.

This study examined the relationship between the GMV and WM microstructure of certain brain regions in patients with PD and early motor improvement after DBS. Our findings clarify the importance of these brain regions in the pathophysiological mechanism of PD and their potential predictive value for DBS motor efficacy and offer new perspectives for promoting the individualization of DBS treatment.