Utility and outcome of piezoelectric bone conduction implant in managing mixed hearing loss with incomplete partition type 2 and enlarged vestibular aqueduct

Stapedial fixation coupled with incomplete partition type 2 and enlarged vestibular aqueduct (EVAS) represents a unique challenge in managing hearing loss owing to the risks of stapedial surgery and the need for alternative hearing restoration methods. This case report describes the selection, implementation, and outcomes of an Osia-2 implantable bone conduction device in a 17-year-old male patient with severe bilateral mixed hearing loss. Seventeen-year-old male patient with severe to profound bilateral mixed hearing loss due to incomplete partition type 2 and EVAS in the presence of audiolotical findings of stapedial fixation. His bone thresholds pure tone average of 40 dB hearing level and an air thresholds PTA of 70 dB hearing level. A nonsurgical bone conduction hearing assistive device demonstrated improved sound performance and high patient satisfaction. Subsequently, an OSI200 implant was used. A posteroinferior incision was created with the BI300 carefully placed 6.5 cm from the external auditory canal. The postoperative outcomes were remarkable, suggesting air-bone gap over-closure with an Osia-aided PTA of 31.67 dB hearing level and an aided speech discrimination score of 96%. Notably, the unaided bone conduction hearing remained unchanged, underscoring the efficacy of the implant in enhancing auditory function without compromising residual hearing. The patient maintained stable hearing levels up to 18 months, confirming the durability of hearing preservation and gain. This case underscores the efficacy of the OSI200 device in managing severe mixed hearing loss in patients with inner ear anomalies, such as incomplete partition type 2 and EVAS. The smooth soft drilling needed for the BI300 implant, and posterior placement, thus improving hearing without altering the unaided bone conduction thresholds.