Contralateral Routing of the Signal Amplification Strategies

ABSTRACT

Contralateral routing of the signal (CROS) fitting applications have been an important remediation for individuals with single-sided deafness (SSD) since the 1960s when Earl Harford and colleagues at Northwestern University reported its use. Since that time, CROS and bilateral contralateral routing of the signal (BICROS) have remained popular fitting options for those with SSD. Over the past decade and a half, digital signal processing, along with other technological advances, has increased the fitting flexibility of wired and wireless CROS devices. This article will review the most current commercially available CROS and BICROS amplification strategies. Additionally, studies evaluating the efficacy and effectiveness of CROS fittings will be reviewed. Finally, a systematic approach to verifying and validating CROS/BICROS fittings will be examined.

KEYWORDS

Single-sided deafness (SSD) - head shadow effect - head-related transfer function - contralateral routing of the signal (CROS) - bilateral contralateral routing of the signal (BICROS)

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