Brain step tumor and otoneurologic manifestations: report of a case with autopsy.

The otoneurologic findings in a 30-year-old male patient who died of a brain stem tumor have been correlated with the histopathology of the temporal bones and brain. The patient was examined on two occasions. A sensorineural hearing loss, which was moderate in the right ear and mild in the left ear, was found. Abnormal vestibular function, indicative of central pathology, was also demonstrated. The right side of the medulla oblongata and pons was largely replaced by the tumor. The cochlear and vestibular nuclei and their connecting fibers were involved with the tumor. Histopathological changes were more prominent in the right cochlea and VII nerve than in the left and were minimal in the vestibular portion of the labyrinths. The otoneurological finding suggested a central nervous system (CNS) lesion, and the morphologic observations confirmed the central origin of the symptoms and signs. Manifestations of lesions of the central auditory and vestibular pathways are discussed.