ear, nose, and throat disorders
Hearing Loss
Single Sided Deafness
Patients with single-sided deafness (SSD) represent a special challenge. In one-on-one situations, hearing and speech understanding is relatively unaffected. However, with noisy backgrounds or complex acoustic environments (eg, classrooms, parties, meetings), patients with SSD are unable to hear and communicate effectively. Further, patients who hear out of only one ear are unable to localize the origin of sounds. The "head shadow" effect is the skull's ability to block sound coming from the deaf side from reaching the hearing ear. This can result in up to a 30 dB loss of sound energy reaching the hearing ear (as a comparison, a store-bought ear plug results in a 22 to 32 dB drop in hearing, roughly equivalent). For many patients, SSD can be life-altering and lead to significant disability at work and socially. Treatment for SSD includes contralateral routing of signal (CROS) hearing aids or bone-anchored hearing implants that pick up sound from the deaf side and transfer it to the hearing ear without the loss of sound energy. Although these technologies improve hearing in noisy settings, they do not allow sound localization. Cochlear implants are increasingly being used with success in patients with SSD, particularly if the deaf ear also has severe tinnitus; implants have also been shown to provide sound localization. 