Implantable Hearing Aids

*Advances in Rehabilitation of Hearing Loss*

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**Chapter 5**

**Abstract**

Congenital Aural Atresia: Hearing

Rehabilitation by Bone-Anchored

*Giampietro Ricci, Arianna Di Stadio, Valeria Gambacorta* 

Auris atresia (AA) is a congenital pathology characterized by aplasia or hypoplasia of the external ear with associated middle ear malformation. The AA has a different degree of severity, and the severe form of the disorder presents no identifiable ear canal (complete atresia) and absence or significative underdevelopment of the middle ear structures. Sometimes AA is associated with a malformation of the ear called "microtia." The alterations of the external auditory canal and of the middle ear structures are responsible for the conductive hearing loss which affects the patients. The hearing restoration procedures may recreate a normal external and middle ear anatomy to favor the recovery of the hearing function, or the surgeon may simply restore the hearing capacity through bypassing the malformed structures by boneanchored hearing implants (BAHIs). The restoring of normal anatomy is generally associated with episode of restenosis of the external ear canal due to bony regrowth. The formulation of a therapeutic strategy may be supported by using Jahrsdoerfer classification to identify the severity of malformation. In the chapter we discuss various bone anchoring prostheses currently used (Baha, Ponto, Alpha2 by Sophono, Bonebridge) and the results that can be obtained by the use of these implants.

**Keywords:** congenital aural atresia, hearing loss, hearing restoration, bone-anchored

Congenital aural atresia (CAA) is a congenital malformation of the ear that causes both esthetic and functional impairments. The malformation presents different severities of impairment; CAA may be the only malformation in the body or be

CAA is a failure in the ear development that happens in the first gestation' weeks; the failure may be complete by affecting the external and the middle ear or partial, as, for example, a stenotic external canal with normal middle ear structures. In all cases, the hearing function is impaired, despite having different hearing

Our group showed that independently from the severity of the hearing impairment, children with hearing loss present a reduction of the memory function and scholar abilities [1], so the restoration of hearing function should be considered

associated with other malformation as observed in syndromic patients.

Hearing Implant (BAHI)

*and Antonio Della Volpe*

hearing implant, memory function

**1. Introduction**
