Changes in Working Memory Structural Connectomes During Reduced Intensity Therapy for WNT-subtype Medulloblastoma

Motivation: Cognitive impairment following treatment of medulloblastoma has been associated with white matter structural changes and altered structural brain connectivity. Goal(s): We hypothesized that decreased intensity therapy would reduce acute change in the working memory structural connectome. Approach: Working memory structural connectomes were assessed relative to baseline after 15 Gy craniospinal irradiation (RT), after subsequent reduced-intensity chemotherapy, and during follow-up for 24 children treated for WNT-subtype (WNT) medulloblastoma. Results: Changes after RT or chemotherapy showed small increases in connectivity strength in frontal striatal edges indicating little acute change. Follow-up revealed significant decreases in connectivity of the bilateral connections between caudate/thalamus. Impact: Increased connectivity of frontal striatal edges after therapy and decreased connectivity of caudate/thalamus edges in follow-up for patients receiving reduced intensity therapy for WNT medulloblastoma may indicate a low incidence of acute changes.