Lhermitte-Duclos

This is a case of Lhermitte-Duclos disease, also known as dysplastic cerebellar gangliocytoma. There is an infiltrative T1 hypointense, T2/FLAIR heterogeneously hyperintense lesion centered within the vermis and right greater than left parasagittal cerebellum with associated gyral swelling and effacement of the fourth ventricle. There is no diffusion restriction, and the postcontrast images demonstrate prominent pial vascularity. The tissue swelling and effacement of the fourth ventricle results in slight downward shift of the cerebellar tonsils. Dysplastic cerebellar gangliocytoma are most likely hamartomatous, although the exact etiology remains unknown. Symptoms are secondary to elevated intracranial pressure and obstructive hydrocephalus. The lesion results from derangement of normal laminar cerebellar cellular organization. Initial treatment includes treating hydrocephalus with surgical resection as definitive treatment.