Presentation
Headache
Patient Data
A well defined right cerebellar soft tissue mass lesion exhibiting hypointense signal in T1 WI and hyperintense signal in T2WI and FLAIR with marked heterogeneous and enhancement in the post-contrast study with minimal diffusion restriction with low ADC value.MRI spectroscopic study showing high choline level with marked reduction of NAA curve. The mass exerting mass effect upon the 4th ventricle and mildly dilated supratentorial ventricles and there is also some degree of trans ependymal migration of CSF surrounding the ventricles on T2/FLAIR sequence.
Additionally, there is also leptomeningeal seeding (best seen in the superior cerebellum) that is well seen n the sagittal T1 with contrast.
Case Discussion
Although histological confirmation is not available in this case, a medulloblastoma is felt to be by far the most likely diagnosis.
Medulloblastomas are the most common malignant brain tumor of childhood. They most commonly present as midline masses in the roof of the 4th ventricle with associated mass effect and hydrocephalus.