BAHA

Bone Anchored Hearing aid

ABSTRACT

Bone anchored hearing aid is a very useful technique and use as an alternative to bone conductor devices. Selection of optimal site for abutment placement is necessary to reduce post-operative complications. The use of acrylic ear mould for the positioning of BAHA implant reduces complications regarding to the site selection. The bone conduction is measured at various sites behind the ear, and the most favourable site is determined in respect of sound quality and comfort. Usually, the location of the site is at the post-auricular point which is approximately 50-55 mm away from the external auditory meatus and at the angle of 45 degree to the tragus. It is a novel method which is helping patients to overcome their post-operative complications which were common in past techniques. Key Words Bone anchored hearing aid, acrylic ear mould, thermoplastic template, abutment.

BAHA MDT How we do it

Introduction

Bone Anchored Hearing Aid is an effective treatment for deafness. It relies on the use of bone conduction directly to the cochlea thus bypassing pathology affecting sound transmission in the ear canal or middle ear. Those patients who are recommended for bone anchored hearing aid will assess by the multi- disciplinary team (MDT) in our department. Multi-disciplinary team is responsible for suitability and preoperative preparation, which includes choosing the most ideal site for placement of abutment. Normally, the optimal site for placement of abutment is at the post-auricular point which is approximately 50-55 mm from the external auditory meatus and at the angle of 45 degree to the Tragus1. However, the selection of the most precise site for the implant remains a difficulty for most of the surgeons but the use of mould method results in an accurate positioning of the implant. Inappropriate site selection will result in the disastrous outcomes while drilling step of surgery. To reduce the chances of any postoperative complications regarding implant site, we are using acrylic ear mould for surgical positioning of a BAHA implant. This ear mould helps us and patient to choose the precise site for the implant. This technique represents a fresh method of minimizing the post-operative complication of inappropriate BAHA abutment positioning.

Material and Methods

Most of the patients having hearing problem have assessed in specialized bone anchored hearing aid audiology clinic. The patient will have to complete quality of life questionnaires. This questionnaire is about 18 different aspects of quality of life.

Surgical procedure will not be recommended directly to the patient. Firstly, auditory clinic will issue a trial hearing aid which is to be worn on soft head band and will review in next two weeks. Now after two weeks, if the patient show satisfaction and his hearing problem resolves then the case will be handed to multi- disciplinary team which includes ENT consultant, an Audiologist and a service manager2.

This team will discuss the case thoroughly. After discussion, the case will move forward to audiologist and maxillofacial technicians. Both of them will see the patient jointly for thorough ...