[Cochlear pathology following chronic electrical stimulation in cats].

This study is to follow the faults during safe research of chronic electrical stimulation of auditory nerve. They were surgical trauma; electrode excursion from scala tympani in different periods after insertion, direct current trauma to the cochleas during chronic electrical stimulation due to the stimulator fault. Extensive histopathological changes were observed, including widespread hair cell and spiral ganglion loss and new bone growth. These results have important implications both in the use and design of cochlear prostheses.