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On February 23, 2000 an 88-year old woman presented with complaints of vertigo with associated nausea & vomiting, and pressure in the right ear. She had dizzy spells years ago but claimed they had stopped. She had seen other specialists she stated did not help her. She had a Doppler ultrasound of the carotid arteries, MRI of the head, CT scan, which were negative, and an ENG which was inconclusive. She was placed on Antivert. Except for the bilateral hearing loss, no abnormalities were noted in the ears, nose or throat. Audiometry revealed bilateral moderate to severe senorineural hearing loss. SRT for the right ear was 55dB, 50dB for the left. Discrimination 40% right ear, 60% left ear. ENG revealed diminished caloric response right ear 36% with normal post caloric optic fixation. ECOG revealed increased SP/AP ratio right ear 64%. Increased SP/AP ratio is suggestive of right cochlear dysfunction, consistent with endolymphatic hydrops. Patient was placed on a no CATS diet. Repeat calorics showed reduced vestibular response right ear 34%. Repeat ECOG showed SP/AP ratio was still increased 56%. Four gentamycin infusions were performed in one-week intervals, beginning April 21, 2000 and ending May 12, 2000. Post-infusion, audiometry revealed further threshold elevation for 4,000-8,000Hz. Repeat caloric testing showed no response right ear, including prone position. ECOG within normal limits. Skew deviation 15 degrees to the right. Findings were consistent with vestibular afferent pathways ablation from the right ear. Patient did not have any further dizziness, however, for 4-6 weeks had some imbalance. Patient died of cardiac failure on December 7, 2000 at 3:20 am and the temporal bones were removed six hours later during the autopsy. Temporal Bone Histopathology: Mastoid air cell system and middle ear were unremarkable. There was complete degeneration of superior and inferior vestibular nerves as well as the cristae and maculae. Partial to total cochlear neuronal loss from the 10mm region to the basal end with similar pattern for the hair cells. Gentamycin therapy resulted in complete ablation of vestibular nerves and their sense organs, which is equivalent to surgical sectioning of superior and inferior vestibular nerves.