Tussive presentation in cervicomedullary junction malformations

Two adult patients with craniocervical junction malformations presented with tussive symptom onset. These patients had acute onset of permanent neurologic symptoms. One patient had basilar invagination with tonsilar herniation and the second, a Type 1 Arnold-Chiari malformation with cord widening. Possible mechanisms include: 1) external compression of cervicomedullary structures by posterior fossa tissue that had descended through the foramen magnum secondary to increased intracranial pressure, and 2) parenchymal shear stress secondary to this caudal repositioning of these structures.