[Hearing distribution of idiopathic bilateral sensorineural hearing loss]

We investigated the mode of progression of idiopathic bilateral sensorineural hearing loss diagnosed in patients seen in the Hearing Loss Clinic at the Department of Otolaryngology of Kitasato University Hospital. Entered into the study were 105 patients whose courses could be observed for more than 3 years. Audiograms were taken 1069 times in these 105 patients and were examined with regard to the distribution of hearing levels by frequency. Idiopathic bilateral sensorineural hearing loss was divided into three stages from the aspect of the time of hearing change stages I, II and III. Hearing clustering points of the respective stages were compared with each other. Proceeding from the peak of stage I to that of stage II was found to take place at the same peak as that of stage III. Another peak hearing clustering point was noted at s.o..