Graph Theoretical Analysis of Structural Covariance Reveals the Relevance of Visuospatial and Attentional Areas in Essential Tremor Recovery After Stereotactic Radiosurgical Thalamotomy

• Published in: Frontiers in aging neuroscience Vol. 14; p. 873605
• Main Authors: Bolton, Thomas A W, Van De Ville, Dimitri, Régis, Jean, Witjas, Tatiana, Girard, Nadine, Levivier, Marc, Tuleasca, Constantin
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Research Foundation 23-05-2022; Frontiers; Frontiers Media S.A
• Subjects: Activities of daily living; Aging Neuroscience; Analysis of covariance; Brain; cortical thickness; Drug resistance; Efficiency; Frontal gyrus; graph theory; Human health and pathology; Life Sciences; Magnetic resonance imaging; mean curvature; Neural plasticity; Patients; Precentral gyrus; stereotactic radiosurgical thalamotomy; structural covariance analysis; surface area; Thalamus; Tremor; Tremor (Muscular contraction); surface area; graph theory; cortical thickness; mean curvature; essential tremor; structural covariance analysis; stereotactic radiosurgical thalamotomy; radiosurgery
• ISSN: 1663-4365; 1663-4365
• DOI: 10.3389/fnagi.2022.873605

Essential tremor (ET) is the most common movement disorder. Its pathophysiology is only partially understood. Here, we leveraged graph theoretical analysis on structural covariance patterns quantified from morphometric estimates for cortical thickness, surface area, and mean curvature in patients with ET before and one year after (to account for delayed clinical effect) ventro-intermediate nucleus (Vim) stereotactic radiosurgical thalamotomy. We further contrasted the observed patterns with those from matched healthy controls (HCs). Significant group differences at the level of individual morphometric properties were specific to mean curvature and the post-/pre-thalamotomy contrast, evidencing brain plasticity at the level of the targeted left thalamus, and of low-level visual, high-level visuospatial and attentional areas implicated in the dorsal visual stream. The introduction of cross-correlational analysis across pairs of morphometric properties strengthened the presence of dorsal visual stream readjustments following thalamotomy, as cortical thickness in the right lingual gyrus, bilateral rostral middle frontal gyrus, and left pre-central gyrus was interrelated with mean curvature in the rest of the brain. Overall, our results position mean curvature as the most relevant morphometric feature to understand brain plasticity in drug-resistant ET patients following Vim thalamotomy. They also highlight the importance of examining not only individual features, but also their interactions, to gain insight into the routes of recovery following intervention.