Masses in the internal auditory canal and their differential diagnoses

Objective:

Typical symptoms of masses in the internal auditory canal range from tinnitus through hearing loss to sudden deafness and vertigo. Diagnosis of acoustic neuroma explains these symptoms and is the most common cause of masses in the internal auditory canal. Several treatment pathways are possible. In case of untypical imaging the most suitable management can only be chosen considering the differential diagnoses.

Methods:

A 70-year-old patient with sudden deafness on the left, tinnitus and vertigo was referred to our department. Otoscopic examination showed a normal tympanic membrane. A MRI-scan of the head with contrast medium displayed a mass in typical location of an acoustic neuroma intrameatal on the left although with only slight contrast enhancement.

Results:

CT-scans showed a regular internal auditory canal and no calcifications, therefore diagnosis remained unclear. Initially we suggested MRI- and CT-scans in 6 months to assess growth behavior of the mass. Rehabilitation of hearing function had to be postponed for MRI controls.

Conclusions:

Masses in the internal auditory canal are most likely to be acoustic neuromas, although differential diagnoses like meningeomas, metastases and inflammations should be considered. Likewise rarities like lipoma, lipochoristoma and aneurysm come into consideration. However, without suspected malignancy an observing approach might be suitable if recommended after interdisciplinary case discussion.

Publication History

Publication Date:
18 April 2018 (online)