Cochlear Implantation for Treatment of Single-sided Deafness

This is a research study to determine whether a cochlear implantation (CI) device can improve hearing in people who are deaf in one ear (known as single-sided deafness).

The goal of this study is to further investigate the role of CI in treating unilateral hearing loss and associated tinnitus. Single-sided deafness (SSD) afflicts approximately 60,000 new patients per year in the United States. The most common causes of these single-sided losses are sudden sensorineural hearing loss, Meniere's disease, trauma, and vestibular schwannoma. Patients with SSD face significant difficulty with communicating in the presence of background noise and in sound localization. Another significant problem for some SSD patients is tinnitus, which can be incapacitating and for which there are no therapies available that are considered to be of sufficient reliability to become a standard of care. Difficulty hearing in background noise and increased tinnitus can lead to significant frustration in social situations and contribute to increased isolation and a decreased quality of life. Treatment options for single sided deafness in the United States include contralateral routing of signals (CROS) hearing aids, bone-anchored hearing aids (BAHA) and use of assistive devices to improve the signal-to-noise in group situations. The first two devices take sound from the affected ear and transmit it to the unaffected ear. The last device consists of having a speaker wear a microphone and routing the signal directly to the patient's ear at a louder listening level. Although these devices can improve speech understanding in some patients, studies have shown that use of these devices does not ameliorate tinnitus or sound localization difficulties. Recent European studies have demonstrated that cochlear implantation (CI) can provide significant improvements in both perceived hearing ability and measured speech comprehension and localization in adult and pediatric patients with unilateral hearing loss. This suggests that CI may be a more effective option for this patient population than the CROS, BAHA or assistive devices.