FENESTRA NOV-OVALIS: A NEW OVAL WINDOW FOR THE IMPROVEMENT OF HEARING IN CASES OF OTOSCLEROSIS

Practical, serviceable physiologic hearing of air-borne sound can be surgically restored to the deafened person by fenestrating the external semicircular canal with the technic which I 1 have described, and the improvement, once obtained, can be maintained postoperatively provided: That the fenestration operation is performed in a properly selected case of deafness. That complete or partial closure of the newly created fenestra as a result of osteogenesis or fibrosis does not take place. The fenestra must remain widely patent. After having performed 375 fenestration operations and observed and studied the end results, I am convinced that fenestration of the labyrinth is indicated only in those cases in which air conduction deafness has resulted from stapedial fixation and degeneration of the cochlear nerve has not yet produced impairment of hearing for the conversational frequencies 512, 1024 and 2048. I am equally convinced that desirable late end results cannot be obtained in