LG-77: BRAIN PLASTICITY IN PEDIATRIC LOW-GRADE GLIOMAS

BACKGROUND: Neural plasticity (NP) is a well-known phenomenon in the brain, especially in the context of long-existing lesions. Young age and immaturity are associated with high NP. Low-grade gliomas (LGGs) are slow-growing tumors with good prognosis and are therefore an ideal tumor type to study NP. METHODS: We conducted a retrospective review of 5 patients with LGGs and studied clinical, radiologic, and pathological data for switching handedness. RESULTS: The median age of patients at diagnosis was 51 months (range, 23-93 months). Their median time from switching handedness to diagnosis was 1 month (range, 0.75-60 months). All 5 patients had pilocytic astrocytoma, and none of them had a genetic disorder. Tumors were located in the posterior fossa (n = 2), left basal ganglia (n = 2), and left thalamus (n = 1). Two patients had paralysis, and three had paresis in the dominant hand. All the patients continued to prefer using the non-dominant hand, even though function of the dominant hand had recovered fully in only 1 patient after rehabilitation. CONCLUSION: Switching handedness is a major form of NP identified in 5 of our patients with same tumor type but interestingly diverse locations. Further studies of NP in LGGs are required to better understand these findings. Functional MRI studies at diagnosis and follow-up can provide further insight on the phenomenon of NP in patients with LGGs.