Management of incudostapedial congenital anomalies in stapes surgery

Abstract

Objectives: The management of developmental anomalies of the ossicular chain and otic capsule in stapes surgery tests the otologist’s diagnositic skills and flexibility in technique and prosthesis choice. Although congenital malleus fixation and perilymph gusher are important clinical entities that have received considerable attention in the otolaryngology literature, congenital anomalies of the incus and stapes are less well described, can often be subtle, and have a distinct influence on management choice and hearing outcome. Methods: A review of over 200 stapes procedures yielded 8 cases of identified congenital anomalies of the stapes or incudo-stapedial complex including congenital absence of the footplate and malformed incus, columellar stapes, and incudo-stapedial joint fixation to the promontory. The developmental anatomy and surgical technique in each case is reviewed and hearing outcome presented. Results: The management technique for each case varied depending on the nuances of the ossicular anomaly and whether both the stapes and incus were affected. All 8 ears (7 patients) that underwent a stapes procedure for either an isolated congenital stapes anomaly or a combined incudo-stapedial anomaly experienced improvement to within 10 dB air-bone gap on postoperative audiometry. Conclusions: Despite unanticipated findings of congenital anomalies of the stapes and incus during middle ear exploration for conductive hearing loss, a flexible and creative management approach can lead to successful hearing outcomes.