Longitudinal multimodal MRI assessment of glymphatic changes after subthalamic nucleus deep brain stimulation in Parkinson disease

Abstract Effects of subthalamic nucleus deep brain stimulation (STN-DBS) on glymphatic-related MRI markers in Parkinson disease (PD) are unclear. We conducted a longitudinal multimodal MRI study on 38 patients with PD who underwent bilateral STN-DBS with a 3T MRI-compatible DBS system and completed paired preoperative and one-year postoperative imaging. Three MRI-derived glymphatic-related markers were evaluated: global BOLD-CSF coupling strength, diffusion tensor imaging along the perivascular space (DTI-ALPS), and MRI-visible perivascular space (PVS) count. gBOLD-CSF coupling strength increased (95% CI, 0.021-0.200; P = 0.0173) significantly after STN-DBS, whereas DTI-ALPS and PVS count did not show statistically significant longitudinal changes. Greater postoperative enhancement of gBOLD-CSF coupling was associated with greater improvement in Parkinson Disease Sleep Scale scores (Spearman rho = 0.531, P = 0.0006; FDR q = 0.0048) and showed a nominal association with LEDD reduction (Spearman rho = 0.389, P = 0.0159; FDR q = 0.0636). In contrast, longitudinal changes in DTI-ALPS and PVS count were not significantly associated with clinical improvement. These findings suggest that functional BOLD-CSF coupling may be a sensitive MRI marker of postoperative glymphatic-related change after STN-DBS.