One hundred and seventy-five surgically treated malformations of the external and middle ear: findings and results

During 10 years 222 patients suffering from malformation of the external and/or middle ear came for treatment to our clinic. One hundred and fifty-seven have been operated on, 139 on one side, 18 bilaterally. This report is based therefore upon 175 cases and deals especially with findings seen during operation, methods of reconstruction and results achieved. Thirty-six patients showed a stenosis of the external meatus, 78 had a partial or complete aplasia. In 61 ears exclusive malformation of middle ear structures was the cause of hearing loss (anomalies of malleus 58.2%, of incus 58.8% and of the stapes nearly always: 172 out of 175 ears). Combinations were frequent. Three structures may affect the development of the ossicular chain, when showing abnormal development themselves: 1) facial nerve, 2) a persistent stapedial artery and 3) the chorda tympani. Anomalies of the course of the facial nerve have been found in 87 ears. In 60 cases these deviations of the course caused obviously a malformation of the ossicular chain, too. A persistent stapedial artery has been seen in six ears. The stapes footplate was always fixed. In four patients a lateral deviation of the chorda tympani's course caused an interruption of the ossicular chain, mainly between the head and the handle of the malleus. The long process of the incus was involved, too, in different degree. The ratio between one-sided and bilateral aplasias was about 2:1. Our method to reconstruct the external meatus is described in detail. The functional results were very satisfying in exclusive anomalies of the ossicular chain.(ABSTRACT TRUNCATED AT 250 WORDS)