Vol.96 No.3 contentsPRACTICA OTO-RHINO-LARYNGOLOGICA
Vol. 96 No. 3 March 2003
A Case of Mixed Hearing Loss Accompanied
with Multiple Congenital Malformations
Kazumasa Kondoh, Tetsuo Morihana and Shin-ichi Okumura
(Osaka Rosai Hospital)
Tadashi Kitahara
(Osaka University)
We report a case of mixed hearing loss accompanied by multiple malformations in a 5-year-old male. His mother first suspected that her child had reduced hearing, when he was 5-years and 2-months-old. Nine months later, she brought her son for a hearing test. Audiometry showed a mild low frequency mixed hearing loss bilaterally.
As a past history, he had a ventricular septal defect and hypoplasia of the bilateral big toes. Family history was noncontributory; there was no history of a similar illness in other family members or relatives.
We peformed exploratory surgery. The round window niche was obscure and the circumferential bony wall of the cochlea was thin. So we abandoned the surgical attempt at hearing improvement.
In the embryo, the differentiation period of each organ varies. Accordingly, we considered that some teratogenic factor may have had an effect on the embryo in the 5～6th weeks of viviparity when the differentiation period of the malformed organs overlapped each other.
Key words : mixed hearing loss, multiple malformations, middle-internal ear, ventricular septal defect (VSD), big toe