paediatrics Brussels 17

Medulloblastomas

1-5 yr: • Often arise from inferior medullary velum of the vermis • Usually presents as a midline tumor • Spherical pattern of growth, projecting into enlarged 4V • Hydrocephalus at diagnosis in 95% of case

6-9 yr + older: • Sometimes mimics cerebellopontine angle tumor • More often in cerebellar hemispheres