Bilateral Congenital Absence of the Stapes Superstructure in Two Siblings

Abstract

Middle ear ossicle malformations are an uncommon event. Among them, the congenital absence of the stapes is a very rare condition that is seldom described in the literature. We report the cases of two women, aged 19 and 22 , who presented with a long history of conductive deafness. An exploratory tympanotomy was performed and the absence of the stapes superstructure and an abnormal position of the facial nerve could be observed. A bone anchored hearing aid (BAHA) was implanted in both patients with good results. It is believed that stapes agenesis is related to an abnormal development of the facial nerve, which by the 5th to 6th week of gestation would interpose between the otic capsule and the stapes blastema, preventing these structures from contacting. A long history of nonprogressive hearing loss from birth or early childhood is the key to reach a diagnosis. Several treatment options have been described. The authors opted for a hearing aid due to the high risk of facial nerve lesion, with good functional results.

Bilateral stapes agenesis: What can we find?

“…Among the 12 reported cases of stapes agenesis in literature (Table 1) [1][2][3][4][5][6][7][8], 8/12 (66.7%) showed a bilateral agenesis. There is a male predominance 8/12 (66.7%).…”

“…There is a male predominance 8/12 (66.7%). Interestingly, two pairs of siblings were reported [5,8]. The most common associated anomalies reported being either a dehiscent facial canal or displaced facial nerve (7/12, 58%).…”

Congenital polypoid cutaneous adnexal and mesenchymal hamartoma: an underdiagnosed entity – Report of two cases

“…This condition has been described as an isolated event or in association with other head and neck anomalies, including accessory tragus and SMH [ 5 ] . The fi rst patient presented with a long history of conductive deafness due to congenital agenesis of the stapes.…”