Minimal invasive pocket technique for magnet bone implant hearing aid without fixation.

INTRODUCTION: The BAHA (bone-anchored hearing aid) Attract is a magnetic transcutaneous bone conduction device anchored into the temporal bone. The standard surgical technique for BAHA Attract is a multi-tools time-consuming process, which requires a large cutaneous incision. The objective of this study is to describe and test the feasibility of a minimally invasive pocket (MIP) technique for Magnet Bone Implant Hearing Aid (MBIHA) with a modified magnet of BAHA Attract without fixation and without any tissue reduction. We use a 3-cm vertical skin incision and a subperiosteal pocket.

METHOD: A study of 10 patients with conductive or mixed hearing loss who benefited from a MBIHA using the MIP technique is presented. The pure tone average (PTA) (dB) for air-conduction thresholds and the speech recognition threshold (SRT) (dB) in speech audiometry in quiet are calculated. The Entific Medical Systems (EMS) questionnaire and the postoperative clinical outcomes are realized.

RESULTS: We found a significant improvement of 33.8 dB on average for the PTA and 44.8 dB for the SRT with MBIHA at 3 months, compared with unaided situation. No implant was removed or displaced after 2 years of follow-up. The skin condition remains intact in all the cases.

CONCLUSION: The minimally subperiosteal pocket surgical technique MIP without fixation and with tissue preservation for the MBIHA is safe, rapid and effective for patients with conductive or mixed hearing loss. It opens new perspectives of development and modify conventional concept in magnetic coupling of bone-conducted device.