Transposition of the facial nerve in congenital aural atresia

It is generally recognized that surgery for congenital aural atresia is difficult. The success or failure of the operation is often directly related to the degree of development of the middle ear. In poorly developed middle ears, the facial nerve may overhang and conceal the oval window niche, making this area inaccessible to inspection, let alone manipulation. The criteria for transposing the facial nerve are; (1) the atresia must be bilateral, (2) there must be preoperative imaging evidence of a stapes and/or patent oval window, (3) there must be no large blood vessels feeding or draining the facial nerve, and (4) facial nerve monitoring must be available. Over the past 2 years, 6 of 94 patients undergoing surgery for atresia were operated with an intent to transpose the facial nerve in order to access the oval window. In all patients, it was impossible to see the oval window niche due to a displaced nerve. In four of six cases, the facial nerve was transposed. The ossicular chain was reconstructed with a total ossicular replacement prosthesis. In no case was there a postoperative facial paralysis or paresis. Facial nerve transposition allows a final chance of achieving serviceable hearing through surgery. The lack of facial nerve injury and the potential for hearing restoration make this procedure feasible in otherwise marginal or poor surgical candidates.