The fifty-one ears with congenital aural atresia (CAA) were examined not only radiologically but also audiologically.
1. Radiological examinations showed the followings:
1) There were six ears with partial atresia and forty five ears with complete atresia.
2) Middle ear anomalies were found in 40 ears (78%).
3) Inner ear anomalies were found in 3 ears (6%).
2. Audiological examination revealed the followings:
1) The average air conduction level was 66±15dB, while the average bone conduction level was 17±17dB.
2) The numbers of ears with bone conduction hearing level more than 20dB even in one frequency were 45 (88%).
3) The average air conduction hearing level was almost same throughout 6 frequencies, while the average bone conduction hearing level were severer in higher frequencies.
3. All cases were divided according to Henner's classification, and the results revealed that about 70% of unilateral CAA ears and 80% of bilateral ears were operable. Also, this classification reflected the hearing level quite well.