Obliterative otosclerosis症例の検討

抄録

There have been few reports on Obliterative otosclerosis in Japan, in which the footplate is thickened, the oval window niche is filled-in in varying degrees. A drill-out procedure is usually required to perform a stapes surgery. Computed tomography (CT) of the temporal bone is useful as a preoperative evaluation of obliterative otosclerosis in some cases. But, in others, preoperative diagnosis is difficult, and the thickened footplate is identified only at surgery.
In the present study, 7 ears of obliterative otosclerosis of 5 patients were reported. The preoperative CT detected the thickened footplates in 6 ears of 4 patients (85.7%). Stapedotomy with the Skeeter drill was successfully performed in all cases, with an improvement more than 15dB in air conduction and preserved bone conduction threshold. Cases that have air-bone gap with bone-conduction threshold elevation at 4kHz, early onset of hearing loss and rapid progression may be related to obliterative otosclerosis.