Neurologic impairment and brain microstructural-functional alterations in infantile spasms: A multimodal magnetic...

Infantile spasms (IS) are associated with significant neurodevelopmental impairments, yet the underlying brain microstructural and functional alterations remain poorly understood. This study aimed to investigate gray and white matter abnormalities in IS patients and their correlations with neurological dysfunction using advanced neuroimaging techniques.

Thirty-four IS patients (21 males, age = 2.8-64.4 months) and 32 age- and sex-matched healthy controls (HC) underwent high-resolution magnetic resonance imaging. Voxel-based morphometry (VBM) and surface-based morphometry (SBM) were employed to analyze gray matter volume (GMV) and cortical thickness, respectively. Diffusion tensor imaging (DTI) assessed white matter integrity. Cognitive and motor functions were evaluated using the Bayley Scales of Infant Development-II.

IS patients exhibited significantly lower Mental Development Index (MDI; 50 vs. 99, p < .001) and Physical Development Index (50 vs. 106, p < .001) compared to HC. VBM revealed reduced GMV in bilateral inferior temporal gyri (BA20/37), left middle occipital gyrus (BA19), right precentral gyrus (BA6), posterior cingulate gyrus, and parahippocampal regions (p < .001). Cortical thinning (by SBM) was observed in the right parahippocampal gyrus, supramarginal gyrus, and left middle temporal gyrus. DTI demonstrated decreased fractional anisotropy in corticospinal tracts and hippocampal-cingulum pathways (p < .05). GMV in the left middle occipital gyrus correlated positively with MDI scores (r = .42, p = .02).

IS patients exhibit widespread microstructural abnormalities in brain regions critical for visual, auditory-language, motor, and limbic functions. These structural deficits, particularly in the occipital and temporal cortices, may underlie the neurodevelopmental impairments observed in IS. The findings highlight the importance of early neuroimaging to identify anatomical correlates of dysfunction and guide targeted interventions.