Localization by unilateral BAHA users

Abstract

Patients with unilateral hearing loss report difficulty hearing conversation on their impaired side, localizing sound, and understanding of speech in background noise. The bone-anchored cochlear stimulator (BAHA) (Entific, Gothenburg, Sweden) has been shown to improve performance in persons with unilateral severe-profound sensorineural loss (USNHL). The purpose of this study is to evaluate the effectiveness of BAHA in sound localization for USNHL listeners. Prospective study of 12 USNHL subjects, 9 of whom received implants on the poorer hearing side. A control group of 10 normal hearing subjects were assessed for comparison. Localization with and without BAHA was assessed using an array of 8 speakers at head level separated by 45 degrees. Error analysis matrix was generated to evaluate the confusions, accuracy in response, and laterality judgment. The average accuracy of speaker localization was 16% in the unaided condition, with no improvement with BAHA use. Laterality judgment was poorer than 43% in both aided and nonaided conditions. Patients with UNSNHL had poor sound localization and laterality judgment abilities that did not improve with BAHA use.