A systematic review of brain morphometry related to deep brain stimulation outcome in Parkinson’s disease

Abstract

While the efficacy of deep brain stimulation (DBS) is well-established in Parkinson’s Disease (PD), the benefit of DBS varies across patients. Using imaging features for outcome prediction offers potential in improving effectiveness, whereas the value of presurgical brain morphometry, derived from the routinely used imaging modality in surgical planning, remains under-explored. This review provides a comprehensive investigation of links between DBS outcomes and brain morphometry features in PD. We systematically searched PubMed and Embase databases and retrieved 793 articles, of which 25 met inclusion criteria and were reviewed in detail. A majority of studies (24/25), including 1253 of 1316 patients, focused on the outcome of DBS targeting the subthalamic nucleus (STN), while five studies included 57 patients receiving globus pallidus internus (GPi) DBS. Accumulated evidence showed that the atrophy of motor cortex and thalamus were associated with poor motor improvement, other structures such as the lateral-occipital cortex and anterior cingulate were also reported to correlated with motor outcome. Regarding non-motor outcomes, decreased volume of the hippocampus was reported to correlate with poor cognitive outcomes. Structures such as the thalamus, nucleus accumbens, and nucleus of basalis of Meynert were also reported to correlate with cognitive functions. Caudal middle frontal cortex was reported to have an impact on postsurgical psychiatric changes. Collectively, the findings of this review emphasize the utility of brain morphometry in outcome prediction of DBS for PD. Future efforts are needed to validate the findings and demonstrate the feasibility of brain morphometry in larger cohorts.

The Related Factors and Effect of Electrode Displacement on Motor Outcome of Subthalamic Nuclei Deep Brain Stimulation in Parkinson’s Disease

“…Decreased brain volume and increased electrode displacement were associated with reduced motor improvements following STN-DBS. The brain atrophy results were consistent with previous studies, which found that the ventricular volume and atrophy of the motor cortex and thalamus were associated with poor motor improvement after DBS [34,35]. In terms of electrode displacement, Choi et al [36] analyzed the impact of brain shift on subcallosal cingulate DBS and found that electrode displacement decreased the connectivity between the electrode and ventral striatum.…”

Revealing Connectivity Patterns of Deep Brain Stimulation Efficacy in Parkinson’s Disease

“…High beta and gamma cortical synchronization were shown to be increased by DBS as evaluated by MEG, especially in the motor, occipitoparietal, temporal, and prefrontal regions. This was discussed as non-normalizing functional connectivity caused by DBS 34 . The low gamma band displays the whole brain increases in DBS ON.…”

Brain morphometry is not associated with non-motor outcomes after deep brain stimulation in Parkinson’s disease

“…4,5 Their widespread clinical application, however, is limited by the need for additional and sometimes time-consuming scanning protocols and the expertise to analyse and translate their results. 6 Therefore, the association of postoperative outcomes with metrics based on T1weighted sequences obtained in clinical routine during surgical planning has been investigated. Particularly, analyses focussing on morphometric tissue features, such as voxelbased morphometry (VBM), have lately received increasing attention to monitor clinical progression and treatment effects.…”

“…Particularly, analyses focussing on morphometric tissue features, such as voxelbased morphometry (VBM), have lately received increasing attention to monitor clinical progression and treatment effects. 6 In a recent meta-analysis including 1253 patients enrolled in 24 studies, Wang and colleagues identified specific areas whose morphometric features were associated with outcomes following STN-DBS. 6 Here, atrophy of the motor cortex and thalamus was associated with below-average improvement in motor symptoms.…”

“…6 In a recent meta-analysis including 1253 patients enrolled in 24 studies, Wang and colleagues identified specific areas whose morphometric features were associated with outcomes following STN-DBS. 6 Here, atrophy of the motor cortex and thalamus was associated with below-average improvement in motor symptoms. On the other hand, outcome prediction of non-motor symptoms has received little attention, with studies focusing on cognitive decline and immediate psychiatric alterations such as postoperative confusion, delirium, and impulsivity.…”