The forgotten herniation

When grossly describing the autopsied brain, we all comment on uncal, cerebellar tonsillar, and subfalcine herniation -- usually as a pertinent negative. But few of us mention external herniation, which can be more colorfully referred to as 'fungus cerebri'. This results from protrusion of brain parenchyma from the cranial cavity when there is a traumatic or surgical defect in the skull.