人工内耳におけるｐｒｏｍｏｎｔｏｒｙ ｔｅｓｔの問題点 ｒｏｕｎｄ ｗｉｎｄｏｗ ｔｅｓｔの試み

Abstract

The electric stimulating threshold of the preoperative promontory test was compared with the postoperative threshold in the electrode of the cochlear implant and with the threshold of the warble-tone audiometry, vowel confusion test, consonant confusion test and the speech tracking test with the use of a speech processor postoperatively. In one patient in whom the reactivity of the promontory test was insufficient, tympanotomy was performed under local anesthesia before the cochlear implant operation, and the stimulating threshold was measured with the electrode placed directly on the round window membrane (round window test). There was no correlation between the result of the promontory test and the postoperative performance of the cochlear implant. The round window test is better than the promontory test for evaluating the performance of a cochlear implant.