Clinical Outcomes With an Osseointegrated Steady State Bone Implant (Osia 2)

Introduction: This study is a retrospective review of a single institutional experience implanting an osseointegrated, steady-state hearing implant (Cochlear Osia-2). The purpose of the study was to review surgical findings and clinical outcomes. To our knowledge, this is the largest study to date investigating this implant.

Methods: Osia-2 cases performed at our institution from 2019-22 were retrospectively reviewed. Indications for surgery included conductive, mixed, and sensorineural hearing loss. Cases involving explantation of an existing percutaneous implant and immediate re-implantation of an ipsilateral Osia-2 were also included. Exclusion criteria included follow-up < 6months. Data reviewed included demographic/descriptive variables, incision type, depth of bone implantation, special hemostatic measures, perioperative complications, device retention, and preliminary analysis of hearing outcomes and patient satisfaction.

Results: At total of 65 patients/72 implants were included. The most common indications were mixed hearing loss in patients with chronic ear disease (52%), and aural atresia (24%). Eight patients underwent an implant explantation/re-implantation of the Osia-2. 15 and 24 implantations were performed on patients > 60 and < 21 years of age, respectively. Seven patients age < 12 years were implanted. Bone quality was insufficient in two cases. Extended methods of hemostatic control were necessary in 6 cases (vessel ligation). 3 patients experienced post-operative complications (4.6%, 2 hematomas, 1 extrusion) with one patient requiring explantation. Device retention rate was 97%, with no patients rating their experience lower than very good to excellent in this cohort. Mean follow up was 15.5 months.

Conclusions: Use of an osseointegrated, steady-state hearing implant system powered by an internal digital piezo-electric transducer was safe and effective. Patients of variable age and clinical indication derived good outcomes. Intra-operative bleeding and hematoma were the two most common complications encountered.