抄録
The Difference Limen Test has been employed recently to determine the location of impairment causing difficulty of hearing due to defective auditory system. The results of this test given to the patients who were hospitalized in the author's clinic to undergo the operation to improve hearing show a tendency that the discrimination index for the otitis media chronica perforativa is somewhat smaller than that for the normal ear.
The relation between the differences of discrimination indexes for 250 cycles, 1000 cycles and 4000 cycles before and after the operation and the hearing after the operation, and the case of the small discrimination index at 250 cycles before the operation, are discussed. Also a comparative study was made of the discrimination index before the operation and a great improvement of hearing after the operation.
