Cochlear Fistula in Chronic Otitis Media with Cholesteatoma

Objectives: Labyrinthine fistula is a common complication of cholesteatoma. It usually locates to the lateral semicircular canal. Cochlear fistula is extremely rare with only few cases described in the literature. We aimed to report four cases of cochlear fistula complicating cholesteatoma.

Material and methods: We retrospectively reviewed 4 cases of cochlear fistula in chronic otitis media with cholesteatoma. We analyzed preoperative clinical, audiological and radiological aspects, and postoperative course.

Results: All patients had chronic otitis media with cholesteatoma, and 3 had already been operated on. In the four cases, we observed severe vertigo while cleaning the external ear canal, particularly when suction was used at the level of the promontorium. Hearing tests revealed mixed hearing loss in all cases (none of the patients had preoperative total deafness). CT scan showed the cochlear fistula in all cases. The 4 patients underwent surgical resection of the cholesteatoma (canal wall up procedure in 1 case and canal wall down in 3). Immediate postoperative course was marked by severe but transient vertigo and total deafness in the 2 cases where the fistula was opened, despite immediate proper sealing. In 2 cases, the fistula was not opened because of the presence of granulation tissue sealing the fistula medially to the cholesteatoma matrix and hearing did not worsened.

Conclusion: Cochlear fistula is a rare but severe complication of middle ear cholesteatoma. Vertigo while cleaning the ear canal at the level of the promontorium should alert the otolaryngologist. CT scan is the technique of choice to identify the bony erosion of the promontorium. The surgeon should be aware of the main risk of postoperative total deafness and transient vertigo for preoperative patient counseling.