Left sided asymmetric sensorineural hearing loss. There is an enlarged left vestibular aqueduct. There also appears to be deficient bone overlying the superior semicircular canal. There is a somewhat prominent venous flow void in the cerebellopontine angle cistern, but the cranial nerve 7 and 8 complexes are intact. There is no evidence of mass lesions. The mastoid air cells and middle ears also appear unremarkable.Right: The cranial nerve 7 and 8 complexes are intact. There is no evidence of mass lesions. The inner ear structures, including the cochlea, vestibule, endolymphatic duct, and semicircular canals, appear unremarkable. The mastoid air cells and middle ears also appear unremarkable.
Enlarged left vestibular aqueduct and apparent deficient bone overlying the superior semicircular canal, which may represent dehiscence, but no evidence of retrocochlear or inner ear lesions. A temporal bone CT may be useful for further evaluation.