Article

Surgical Placement and Efficacy of a Bone-anchored Hearing Aid in a Dog with Conductive Deafness

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Abstract

The surgical placement of a bone-anchored hearing aid (BAHA), was investigated in a dog with chronic otitis. It had been treated by bilateral total ear canal ablation and lateral bulla osteotomy (TECALBO). The dog was then fitted with a bone-anchored hearing aid (BAHA). A titanium fixture was placed in the left parietal bone and allowed to osseointegrate for 126 days. Further surgery and tissue reduction allowed the fitting of a titanium abutment, and 21 days later the hearing aid was attached. Auditory function with and without the hearing aid was tested by brainstem auditory evoked response (BAER) using a free-field alternating click stimulus (2-4kHz), at 16cm from the head. With the BAHA in place, BAER tests showed a hearing threshold of 30dB sound pressure level (SPL), while without the BAHA no BAER trace was reproducible even at 70dB SPL.

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