A labyrinthine, or perilymph, fistula is an abnormal communication between the inner and middle ear. This communication causes perilymphatic fluid to leak from the inner to the middle ear. Patients present with acute vertigo and sensorineural hearing loss. A labyrinthine fistula can occur in adults and children. They are more typically acquired but may also be congenital.

This is considered an otologic emergency due to the possibility of permanent sensorineural hearing loss in the affected ear with or without repair.

Infection, prior ear surgery, and trauma are common causes of fistula formation. In congenital cases, recurrent meningitis may result from the congenital anomaly.

Labyrinthine fistulae are surgically repaired, although rarely they may spontaneously heal. Patients should be instructed to remain on bed rest with an elevated head of the bed.