After confirming that potential study participants meet basic demographic inclusion criteria, patients will be evaluated by Dr. Daniel Lee, a pediatric neurotologic surgeon at MEEI. A detailed history will be obtained and physical exam will be completed. Subjects will also be evaluated for baseline qualitative measures using questionnaires and quantitative measures using audiologic testing. In particular, audiometric threshold testing will be completed to determine acoustic auditory status and confirm that all patients have severe to profound deafness. Electrical Auditory Brainstem Response (EABR) evaluation will only be used if the validity of behavioral audiometric testing is in question. These parameters will be compared to inclusion criteria to determine if a subject meets all inclusion criteria and represents a viable candidate for ABI surgery.
All baseline procedures will be completed at the time of screening. In children older than 14 year of age, qualitative measurements using the Abbreviated Profile of Hearing Aid Benefit (APHAB), Modified Hearing Handicap Inventory (HHI), Dizziness Handicap Inventory (DHI), and Quality of Life (SF-36) questionnaires will be included in addition to audiologic tests and speech and language assessments.
Study Drug or Device Procedures:
Subjects will undergo pre-operative evaluation for ABI surgery. Those subjects that are appropriate for surgery will undergo a procedure for implantation of the ABI24 system. As per manufacturer protocol, the parameters of the ABI24 system including adjustment of electrode sensitivities and activation of specific electrodes will be completed at each follow-up visit post-operatively. This process involves adjustment of device parameters by an audiologist who subsequently administers audiologic tests (including psychophysical measures) to confirm optimal activation of the ABI24 device.
Standard of Care Procedures:
All audiologic testing and assessments represent the standard of care. Aspects of our study that go beyond routine standard of care are outlined above and in the informed consent.
Study participants will have audiologic testing and device activation and adjustment completed at follow-up appointments. These post-operative follow-up appointments will occur at 1-2 weeks, 4-12 weeks (initial activation), one week following activation (5-7 weeks), three, six, and twelve months, and biannually thereafter until the study end point of five years. Timing of these appointments may vary by as much as four weeks prior to or after the planned follow-up date (e.g. between 2-4 months for the 3 month follow-up).