A method of distinguishing conductive deafness from perceptive deafness; preliminary report.

REPORTS have already been made on various methods of distinguishing conductive deafness from perceptive deafness in the hearing test. Especially in recent years, examinations applying Fowler's recruitment phenomenon are being employed for this purpose. In the present article we intend to introduce a new Chart 1.—Mean values of hearing acuity in five normal ears ( A ) before and ( B ) after instillation of glycerin. method that is altogether different from those that now exist for distinguishing between perceptive and conductive deafness. This method is a very simple one that almost any otologist can easily try in his testing room: First an audiogram of the ear to be tested is recorded, and then the same test is carried out on the same ear after the instillation of 8 drops of glycerin into the canal, care being taken to place the head in such way that the ear is up and the drum membrane