Introduction: Improvements in MRI resolution over the last decades have facilitated detection of schwannomas of intralabyrinthine origin as cause of sudden and progressive hearing loss. Surgical removal of cochlear schwannomas with synchronous cochlear implantation (CI) has exceeded expectations regarding hearing rehabilitation in individual patients. Radiation therapy of intracochlear schwannomas followed by CI has not jet been systematically investigated.

Method: Consecutive series of four patients with intracochlear schwannomas treated at our institution since 5/2021 by intracochlear spacer insertion through the tumor, definitive radiation therapy, and CI at least one year later.

Results: All patients underwent standard work-up for CI according to the national guidelines, followed by intracochlear insertion of an MED-ELÒ ANTS (Auditory Nerve Test System) electrode confirming auditory nerve function by E-BERA, followed by insertion of an MED-ELÒ insertion probe as spacer. Four weeks later, all patients received stereotactic radiosurgery (SRS) with a dose 12 Gy to the 80% isodose. All patient underwent clinical and MRI follow-up for at least one year. Two patients received MED-ELÒ Synchrony 2 Flex-28 implants after confirmation of stable auditory nerve function by E-BERA utilizing MED-ELÒ ANTS. Two month after implant activation one patient already has an WRS of 50% (65dBHL). Another patient received an Advanced Bionics HiRes Ultra-3D in another institution.

Discussion: Longer follow-up regarding CI performance and tumor control are needed, as well as larger patient collectives, before definitive conclusions can be drawn. Initial results are encouraging to offer "radiation plus CI" as a treatment option in counseling patients for intracochlear schwannomas.

SE, SMF und JS haben Reisekostenerstattungen von MED-EL erhalten. SE und PKP haben Kongressunterestützung von MED-EL erhalten. DP ist Mitrarbeiterin von MED-EL. JD hat keinen Interessenskonflikt.