Association between choroid plexus susceptibility features and motor outcomes following deep brain stimulation in Parkinson's disease.

Abstract

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an effective therapy for advanced Parkinson's disease (PD), but postoperative motor outcomes show substantial interindividual variability. Recent evidence suggests choroid plexus (ChP) dysfunction in PD pathophysiology. This study aimed to investigate the association between preoperative ChP MRI characteristics and postoperative motor outcomes following STN-DBS in PD patients. Forty-one PD patients who underwent bilateral STN-DBS were included for final analysis. Motor outcomes were assessed using the Movement Disorder Society-Unified Parkinson's Disease Rating Scale part III scores at baseline and 6 months after surgery. ChP dysfunction was evaluated by quantifying volume from T1-weighted imaging and extracting susceptibility histogram features from quantitative susceptibility mapping (QSM). Correlation and receiver operating characteristic (ROC) analyses were performed to evaluate the predictive value of ChP imaging metrics. Preoperative total motor scores were positively associated with maximum ChP susceptibility (r = 0.410, p = 0.008), while tremor and rigidity subscores correlated with kurtosis (r = 0.395, p = 0.011) and the 90th percentile (r = 0.356, p = 0.023), respectively, of the ChP susceptibility values. Postoperative total motor improvement showed significant positive correlations with the 10th percentile (r = 0.406, p = 0.009), mean (r = 0.325, p = 0.038), minimum (r = 0.322, p = 0.040), and skewness (r = 0.344, p = 0.028) of ChP susceptibility histogram features. For specific motor symptoms, bradykinesia improvement was positively associated with the 10th percentile (r = 0.394, p = 0.011), minimum (r = 0.335, p = 0.033), and skewness (r = 0.319, p = 0.042) of the ChP susceptibility values. Gait stability improvement correlated positively with the 10th percentile (r = 0.376, p = 0.016), mean (r = 0.379, p = 0.015), and median (r = 0.349, p = 0.026) values of ChP susceptibility. Combining ChP susceptibility histogram features with clinical characteristics achieved an area under the curve of 0.85 for differentiating superior from moderate responders to STN-DBS in terms of total motor outcomes. This exploratory study suggests that ChP microvascular damage and iron dysregulation are linked to preoperative motor severity in PD, while ChP calcification is significantly associated with motor responsiveness to STN-DBS. Combining the susceptibility histogram features of ChP calcification with clinical characteristics may offer additional value for improving patient-specific prognostication.