Lhermitte-Duclos disease presenting with hydrocephalus.

Lhermitte-Duclos disease (LDD) is a rare cerebellar disorder characterized by diffuse or focal enlargement of cerebellar folia. Clinical manifestations are usually related to a mass effect and secondary obstructive hydrocephalus. Increased intracranial pressure symptoms and cerebellar symptoms are the most frequent patient complaints. We describe the case of a patient with LDD who developed secondary obstructive hydrocephalus. A 68-year-old woman was brought to the emergency room for sudden vertigo following several bouts of vomiting and headache. There were no external signs of trauma, serious illness or infection. On admission, the patient was alert and had no neurological deficits. Brain computed tomography (CT) and magnetic resonance imaging (MRI) showed hydrocephalus and a cerebellar mass in the right cerebellar hemisphere compressing the fourth ventricle. Suboccipital craniotomy and subtotal removal of the mass was performed. Pathological study of the surgical specimen showed abnormal ganglionic neurons and an enlarged molecular layer compatible with dysplastic gangliocytoma. Cytoreduction can achieve improvement in symptoms caused by mass effect, but postoperative swelling may aggravate obstructive hydrocephalus. Therefore, if symptoms still remain after removal of the mass, an additional shunting procedure may be needed as a further management option.