Surgical Manegement of Congenital Ear Canal Atresia with Microtia

Abstract

The surgical correction of congenital ear canal atresia is one of the most difficult technique in the field of otomicrosurgery. From 1978 to 198a, 34 ears of 31 cases were operated in our clinic and the results obtained were reported in this paper. The surgical procedure used in this series of operation is a direct drilling method through the tympanic cavity without mastoidectomy. Transplantation of a skintube, made water-tight with a full thickness skin graft is combined with Tanzer's auriculoplasty. Hearing gain 6 months or longer after surgery was excellent in 15/34 ears, excellent but reversed in 1/34 ears, a slight audiometric improvement of over 10 dB in 3/34 ears and less than 10 dB improve ment in 15/34 ears. The reasons for the unsuccessfull 15ears are; fixed stapes (1 ear), stapes aplasia (2 ears), not comfirmed stapes (3 ears), undeveloped tympanic cavity (2 ears), infected cavity (2 ears), impossible to exposure (2 ears), and unknown reason (3 ears). All of 6 cases with grade 1 microtia showed excellent hearing gain, although all 4 cases with grade 4 microtia showed minimum improvement. Fifty percent of the cases with grade 2 and 3 microtia showed excellent hearing gain. The facial nerve was exposed at the external ear canal wall in 3 cases during drilling. One of these exhibited ficial palsy for three month. In one case facial palsy had occured without exposure of the nerve, and a decompression operation was performed with a good recovery in 4 months. In 5 cases with an infected tympanic cavity, tympanomeatoplasty was done and all cases resulted in a discharging ear. In 4 of these cases skin grafting was performed again and excellent hearing gain was achieved in all but one case. Here the tympanic cavity was closed completely, as infection was found to continued even in the second stage of Tanzer's ope ration. In 8 cases, postoperative continuous discharge occured. The cause was an infected tympanic cavity in 5 cases, suture insufficiency of skin tube in 2 cases and exposure of the parotid grand. All of these were re-operated with good results.