This is a report of cochleo-saccular degeneration found in temporal bones from a patient who had suffered from slowly progressive and total sensorineural deafness which had an inherited origin. At age 8, this patient began to complain of hearing loss, and by age 10 she was totally deaf. The patient was 1 of 3 female siblings who have suffered from an exactly identical progressive disease: deafness, absent gastric motility, small bowel diverticulitis and ulceration, and sensory neuropathy. The temporal bone pathology found in this case was the degenerative change in the cochlear duct and sacculus. No pathology was found in the utriculus and semicircular canals.