Neurovascular coupling alterations in children with acute lymphoblastic leukemia after chemotherapy: an ASL and rs-fMRI study.

OBJECTIVE: To investigate neurovascular coupling (NVC) alterations in pediatric acute lymphoblastic leukemia (ALL) patients following chemotherapy using multimodal neuroimaging. METHODS: We combined arterial spin labeling (ASL) and resting-state functional MRI (rs-fMRI) to assess the relationship between cerebral blood flow (CBF) and blood oxygenation level-dependent (BOLD)-derived resting-state metrics, including amplitude of low-frequency fluctuations (ALFF), fractional amplitude of low-frequency fluctuations (fALFF), regional homogeneity (ReHo), and degree centrality (DC), in 23 children with ALL (age range, 7-15 years) and 30 healthy controls (age range, 6-13 years). RESULTS: Children with ALL assessed after chemotherapy showed significant regional differences in NVC indices compared with healthy controls. The ALL group demonstrated significantly lower Perceptual Reasoning Index (PRI) and Full-Scale Intelligence Quotient (FSIQ) scores after adjustment for education (p < 0.05). No significant between-group differences were found in the whole-brain CBF-ALFF, CBF-fALFF, CBF-ReHo, or CBF-DC coefficients (all p > 0.05). Regional NVC analysis revealed consistently reduced ratios in the right middle temporal gyrus and increased ratios in several left-sided cortical and subcortical regions, including the hippocampus, thalamus, and lingual gyrus. After false discovery rate (FDR) correction, no significant correlations were found between regional NVC metrics and cognitive scores (all corrected q > 0.05). CONCLUSION: Children with ALL show altered NVC in multiple brain regions after chemotherapy. However, no direct associations with cognitive scores survived stringent correction, and these findings should be considered preliminary imaging evidence of regional brain functional differences in this population.