Imaging of the Hyrtl Fissure: A Rare Cause of Congenital CSF Otorrhea.

Hyrtl fissure is a rare cause of congenital CSF otorrhea in infants, with only a few cases previously described in the English literature. Given the predisposition to repeated ear and intracranial infections, identification of this bony anomaly is critical in the diagnosis and management of recurrent meningitis or otitis media in a child, especially in the presence of CSF otorrhea. We describe 3 cases of this entity with a specific focus on the embryologic basis of the etiology and conventional and advanced imaging features of this unique entity.