Effects of StereoBiCROS on Speech Understanding in Noise and Quality of Life for Asymmetric Sensorineural Hearing Loss.

Background and Aim: Asymmetric sensorineural hearing loss is difficult to rehabilitate acoustically. Bilateral amplification may induce binaural interference, while CROS/BiCROS systems provide benefit only when the speech signal reaches the poorer ear. A hybrid approach combining CROS strategy with bilateral acoustic amplification, called Stereophonic Bilateral Contralateral Routing of Signal-StereoBiCROS-has recently emerged. Methods: A one-month home trial was conducted with hearing aids programmed in three listening modes: Stereophonic, BiCROS, and StereoBiCROS. Speech-in-noise perception was assessed in dichotic and reverse-dichotic conditions. Speech recognition thresholds were derived using logistic regression. Daily mode usage was extracted from datalogging. Pre/post subjective benefit was evaluated using the SSQ-15 and SF-12. Results: Eighteen participants (mean age 70.7 ± 8.2 years) used the devices 12.4 ± 1.6 h per day, predominantly in StereoBiCROS mode (76.9 ± 24.2%). In the dichotic condition, this mode yielded the best speech-to-noise ratio (0.96 ± 2.74 dB; p < 0.0001), outperforming unilateral rerouting (3.00 ± 2.05 dB; p = 0.001) and bilateral amplification (5.16 ± 1.31 dB; p = 0.001). In the reverse-dichotic condition, only bilateral amplification provided a non-significant improvement (3.08 ± 1.38 dB), whereas the other modes deteriorated intelligibility. SSQ-15 total and subscale scores significantly improved after one month, while SF-12 scores did not change. Conclusions: StereoBiCROS stimulation appears to be a promising acoustic alternative for improving speech intelligibility in noise and patient-reported outcomes in asymmetric sensorineural hearing loss. Further research is required to identify the most responsive audiological profiles.