Incomplete partition type 1 on CT: right sensorineural hearing loss. Internal Auditory Canal: The right cochlea is bulbous and there is deficiency of the modiolus and interscalar septations and communicates widely with the dysplastic vestibule. In addition, the semicircular canal bone island is diminutive with dysmorphic semicircular canals. There also appears to be mild thinning of the cochlear nerve caliber, but the vestibular nerves are intact. The left cranial nerve 7 and 8 complexes are intact. There is no evidence of mass lesions. The left inner ear structures, including the cochlea, vestibule, endolymphatic duct, and semicircular canals, appear unremarkable. The bilateral mastoid air cells and middle ears also appear unremarkable.Brain: There is no evidence of intracranial hemorrhage, mass, or acute infarct. A few scattered foci of cerebral white matter T2 hyperintensity may represent slightly prominent perivascular spaces. The brain parenchyma and pituitary gland otherwise appear unremarkable. There is no abnormal intracranial enhancement. The ventricles and basal cisterns are normal in size and configuration. There is no midline shift or herniation. The major cerebral flow voids are intact. The orbits, skull, and scalp soft tissues are grossly unremarkable. There is minimal scattered paranasal sinus mucosal thickening.
1. Findings compatible with right side incomplete partition type 1 and what appears to be mild cochlear nerve deficiency.2. The intracranial structures are otherwise unremarkable.