Bilateral stapes agenesis: What can we find?

Abstract

We describe the youngest case of bilateral stapes agenesis and systematically reviewed the literature. Among those cases, 8/12 (66.7%) showed a bilateral agenesis. There is a male predominance 8/12 (66.7%). The most common associated anomaly reported being either a dehiscent or displaced facial nerve (7/12-58%). Furthermore, 5/12 patients (42%) had a narrow or an absent oval window. In our case, a 5-year-old male patient was referred for bilateral conductive hearing loss (air-bone gap 65 dB, bilateral). Operating findings on the left side included an inferiorly displaced facial nerve over the promontory, a narrow ossified oval window and an absent stapes. A stapedotomy with insertion of a modified stapes prosthesis allowed us to close the conductive gap. Even with possible good outcomes, surgical management should not be taken lightly, considering amplification is almost always a safe and effective option.

A case of microtia with bilateral conductive hearing loss with unusual findings

“…Less than 12 cases of stapes agenesis have been reported so far. 11 The most commonly reported related malformations are a dehiscent facial canal or a displaced facial nerve in 7 patients out of 12 (58%). It is theorised that facial nerve displacement develops due to a delay in the formation of the first branchial arch.…”