The Benefit of a Wireless Contralateral Routing of Signals (CROS) Microphone in Unilateral Cochlear Implant Recipients

OBJECTIVE Assess speech outcomes in unilateral cochlear implant (CI) recipients after addition of a wireless contralateral routing of signals (CROS) microphone. STUDY DESIGN Prospective cohort study. SETTING Ambulatory. PATIENTS Sixteen adult unilateral CI users with nonserviceable hearing on the contralateral side were recruited. Those with AzBio sentence scores of 40 to 80% or Hearing in Noise Test - Quiet (HINT-Q) scores of 60 to 90% with a CI alone were eligible participants. INTERVENTION Speech testing was carried out with the CROS on and off. MAIN OUTCOME MEASURE Speech recognition. RESULTS In the consonant-nucleus-consonant test presented in quiet from the front, word scores were 64.4 (CI) and 63.8% (CI + CROS) (p = 0.72), and phoneme scores were 80.2 (CI) and 80.8% (CI + CROS) (p = 0.65). In AzBio sentence testing in quiet, with the signals projected from the contralateral, front, or ipsilateral to the CI, speech perception with the CI alone was 60.8, 75.9, and 79.1%. With the addition of the CROS microphone, using the same speaker arrangement, speech perception was 69.8 (p