Alterations in the gray matter volume in transient ischemic attack: a voxel-based morphometry study

Background: Several studies have emphasized that transient ischemic attack (TIA) patients suffered functional impairments, but whether underlying morphological alterations exist remains unclear. This study aims to detect possible gray matter volume (GMV) alterations in patients with TIA using voxel-based morphometry (VBM) method. Methods: High-resolution T1-weighted anatomical images of 21 patients were compared with 21 healthy controls of matching age, gender, and education. Changes in the GMV were observed using VBM technique, followed by two-sample t-test analysis to detect the differences in the GMV between TIA patients and healthy controls. Correlations between the clinical parameters and the Montreal cognitive assessment (MoCA) scores, and the altered GMV in TIAs, were investigated. Results: Two-sample t-test analysis revealed a significant GMV reduction in specific regions in the default mode network (DMN) in TIA patients, including the bilateral medial frontal gyrus, anterior cingulate cortex (ACC), and precuneus. No correlation was found between the reduced GMV and MoCA scores and clinical parameters. Conclusion: Transient ischemic attack patients showed widespread morphology atrophy in DMN, suggesting that, despite the absence of a cerebral infarction, ischemic injury may induce structural abnormalities and eventually contribute to functional impairments in TIA patients. Our results may provide a valuable basis for the pathophysiological mechanism related to the cognitive dysfunction of TIA from the view of brain morphology.