Cochlear implant in patients with sudden unilateral sensorineural hearing loss and associated tinnitus.

INTRODUCTION AND OBJECTIVES To assess the efficacy of cochlear implantation in patients with unilateral sudden sensorineural hearing loss and associated disabling tinnitus. METHODS Ten patients suffering from severe-to-profound sudden hearing loss and tinnitus in the affected ear received implants. The sample was comprised of 4 men and 6 women, with a mean age of 42.7 years (range 34-62) at implantation. The severity of the tinnitus was evaluated with the Spanish validated version of the Tinnitus Handicap Inventory (THI) and a visual analogue scale. These assessments were obtained before and after implantation. RESULTS Tinnitus suppression was observed in 2 patients. In 7 cases, we observed an improvement in the THI, in different degrees, and 1 patient remained without changes. Tinnitus worsening was not found in the series studied. CONCLUSIONS Tinnitus reduction following cochlear implantation can be explained by several mechanisms, such as habituation, acoustic masking, direct stimulation of the cochlear nerve and reorganisation of cortical areas. Even though further research is required, cochlear implantation is an effective method for the treatment of disabling tinnitus in patients with severe-to-profound unilateral sudden sensorineural hearing loss.