OUR EXPERIENCE OF USING AUTOGRAFT AND SYNTHETIC BIOCOMPATIBLE MATERIALS IN DIFFERENT TYPES OF TYMPANOPLASTY AND UTILIZATION OF IMPLANTABLE BONE CONDUCTION HEARING AID
N.S. Dimitriev, S.J.Kosjakov. V.I.Fedoseev
Research Center for Audiology & Hearing Rehabilitation Moscow, Russia
The immediate clinical results and long term observations obtained from about 1000 surgical interventions have shown that the most preferable in tympanoplasty type 1 are wet fascia and tragal cartilage and underlay techniques of myringoplasty as well as conserved costal cartilage for ossiculoplasty in type 2 and 3 tympanoplasties.
In cases when it is impossible to compensate for conductive hearing loss by conservative and surgical methods or, by fitting with the use of air conduction hearing aids, fitting with bone conduction hearing aids is possible. But the patients may be disturbed by the pressure of the transducer and its displacement. The alternative method which allows to avoid all those difficulties is implantable bone conduction hearing aid. We have developed the hearing aid consisting of implantable SmCo5 magnet in titanium container with orthopedic screw and a body worn electronic device with external induction coil. The candidate for the first implantation was a 49 years old female who underwent several unsuccessful tympanoplasties on both ears and then bilateral mastoidectomy 10 years ago. She was proposed to use an implantable bone conduction hearing aid. Her average air conduction hearing thresholds were 60-70 dB and this value for bone conduction hearing thresholds was 20 dB. Two months after implantation the free field hearing thresholds decreased by 25-35 dB at the frequencies of 1, 2, and 4 kHz and by 15 dB at the frequencies of 0.25 and 0.5 kHz. The patient started to use hearing aid for 5-6 hours a day with no signs of skin irritation.