Voxelwise degree centrality alterations and cognitive performance in severe unilateral M1-segment middle cerebral artery stenosis with ipsilateral watershed infarction

Purpose To characterize voxelwise degree centrality (DC) alterations and their exploratory clinical associations in severe unilateral M1-segment middle cerebral artery stenosis with ipsilateral watershed infarction. Methods This cross-sectional study included 40 patients with left-sided disease, 47 with right-sided disease, and 44 healthy controls. Resting-state functional magnetic resonance imaging-derived weighted DC ( r > 0.25) was compared using analysis of covariance with adjustment for educational attainment, Tukey–Kramer testing, and Gaussian random field-corrected patient–control contrasts (two-tailed voxel P < 0.001; cluster P < 0.05). Exploratory clinical associations were assessed using Spearman rank correlation. Results Mini-Mental State Examination (MMSE) scores differed among groups ( P < 0.001), with both patient groups scoring lower than controls; Montreal Cognitive Assessment (MoCA) scores also differed ( P < 0.001), with the left-sided group lowest, the right-sided group intermediate, and controls highest. The left-sided group showed lower DC predominantly in left temporal–opercular and postcentral–inferior parietal regions and higher DC in right medial/subcortical and posterior-midline regions; the largest lower-DC cluster peaked at MNI coordinates −48, −18, 39 ( Z = −5.5420). The right-sided group showed lower DC in right putaminal/insular, temporal, and parietal–sensorimotor regions and higher DC in the left cerebellum; the largest lower-DC cluster peaked at MNI coordinates 48, −27, 36 ( Z = −6.0021). In the right-sided group, exploratory nominal associations were observed between MMSE scores and DC in the left cerebellar, right superior temporal-pole, and right parietal–sensorimotor clusters ( r = −0.300 to 0.421; nominal P = 0.003–0.040). No nominal cognitive–DC correlations were observed in the left-sided group, and no MoCA–DC correlations in the right-sided group. Conclusion Distributed DC alterations accompanied cognitive performance differences, with selective exploratory nominal MMSE associations in right-sided disease. DC may merit further evaluation as a candidate imaging feature of BOLD-based functional alterations associated with cognitive differences.