先天性外耳道閉鎖症の聴力改善について

抄録

Operation was carried out on 34 patients (38 ears) with congenital atresia of the external audiotory canal. Among these audiogram was accurately recorded before and after operation in 9 ears receiving Pattee's operation, 8 ears receiving Wullstein I and 9 ears receiving Wullstein III. Only 7 ears reached within 30 db in practical speech frequencies. The results obtained by Wullstein I (3 ears) proved to be poor, and the reason for this phenomenon was pursued with the otoscope and Schall's sound.
It was noted that even in the cases in whom both the malleus and incus were mobile and in whom subjective hearing had improved during operation, there were some not showing improvement of hearing after operation because of dissociation of the incus-stapes article or hypoplasia. By hypoplasia here means no formation of article although the crus longum ofincus and capitulum of stapes are located adjacent to each other. Sound cannot be fully transmitted under such conditions. In the literature such a report has never been reported excepting for Hough's paper on this subject.