Cavernous malformation of the internal auditory canal. A case report.

A 51 year-old male, complaining of progressive left-sided hearing loss, tinnitus, and unsteady gait, underwent surgery with a probable diagnosis of intracanalicular acoustic neuroma, based on neurological, neurotologic, Computed Tomography (CT), and Magnetic Resonance Imaging (MRI) findings. During surgery, the Internal Auditory Canal (IAC) was opened and a reddish-colored, soft, vascular lesion was found within the VII and VIII cranial nerve complex. The lesion, which resulted to be a cavernous malformation, was removed without any postoperative deficits. This report stresses the diagnostic difficulty to differentiate preoperatively the more frequent acoustic neuromas from other lesions that may develop within the IAC.