Pericallosal lipoma and middle cerebral artery aneurysm: a coincidence?

Intracranial lipomas are rare congenital malformations that can often be seen in association with other brain malformations; agenesis or dysgenesis of the corpus callosum is the most frequently associated brain anomaly. They are usually pericallosal asymptomatic midline lesions. Intracranial lipomas associated with a non-contiguous cerebral aneurysm are extremely rare. We report an infant with partial agenesis of the corpus callosum and pericallosal lipoma associated with cerebral haemorrhage due to a distal middle cerebral artery aneurysm. Such an association is probably not fortuitous and could suggest a pathogenic relationship.