Congenital Oval or Round Window Anomaly With or Without Abnormal Facial Nerve Course

Abstract

Congenital dysplasia or aplasia of the oval and/or round window is an uncommon congenital minor ear anomaly. Classical microsurgical opportunities are rare in this group of anomalies. Newer options for hearing rehabilitation, such as the osseointegrated passive bone conduction devices, have become viable alternatives for conventional air conduction hearing devices. In the near future, upcoming active bone conduction devices might become the most preferred surgical option. In cases in which the facial nerve is only partially overlying the oval window, a type of malleostapedotomy procedure might result in a serviceable postoperative hearing level.

Vestibulotomy With Ossiculoplasty Versus Round Window Vibroplasty Procedure in Children With Oval Window Aplasia

“…Briefly, after a vestibulotomy in the round window area, a classic OPL was performed with a prosthesis connecting either the residual incus, malleus, or chorda tympani (incudostapedotomy, malleostapedotomy, or chordostapedotomy) to the vestibule (6). Briefly, after a vestibulotomy in the round window area, a classic OPL was performed with a prosthesis connecting either the residual incus, malleus, or chorda tympani (incudostapedotomy, malleostapedotomy, or chordostapedotomy) to the vestibule (6).…”

Congenital oval or round window malformations in children: Surgical findings and results in 17 cases

“…Because of the association with facial nerve anomalies or an aberrant course of the facial nerve, surgical intervention can be challenging. Surgical intervention consists of the performance of a stapedotomy, oval window drill‐out procedure, or fenestration of the promontory or lateral semicircular canal fenestration, if possible followed by ossicular reconstruction . Alternatives to surgical treatment are conventional hearing aids or osseointegrated implants …”

Two Cases of Malleostapedotomy in Congenital Oval Window Atresia

“…Thomeer, et al10) performed surgery on 15 ears with congenital anomalies. Three patients underwent incudostapedotomies, and only one (33%) showed an ABG improvement, of 20 dB.…”

“…Various treatments for this anomaly have been introduced: hearing aids,3,4) vestibulotomy,5) fenestration of the horizontal semicircular canal,6,7) and formation of a neo-oval window 8). Also, as Fisch9) reported, incudostapedotomy and malleostapedotomy have been used successfully to treat patients with congenital oval window anomalies 10). However, in patients with accompanying malformations of the ossicles or abnormal routes of the facial nerve, the hearing improvement with previous procedures has not been sufficient.…”