In Reply: Dominance of Ossicular Route in Sound Transmission.

We reported that the degree of conductive hearing loss resulting from a tympanic membrane (TM) perforation would be expected with the size of perforation and pneumatization of middle ear and mastoid, not location of perforation. This result was conflicted with previous study that revealed the influence of location of TM perforation on the severity of hearing loss in 1970 [1].

When the perforation size was relatively large, the sound transmission via acoustic route would became dominant and air-bone gap would increase more by phase cancelation at round window in posterior TM perforation rather than in anterior TM perforation [2, 3]. Unfortunately, most of patients who were included in our study had small perforation size within 30% of TM (n=34/44, 77%). The authors agree with your comments which we did not mention in the discussion.