Objective: To determine whether new technology for intraoperative evoked compound action potential (ECAP) threshold measurements-the CR120 Intraoperative Remote Assistant device-is comparable to the existing Custom Sound(®) clinical system, as well as assess test-retest accuracy of the systems.
Design: Within subject, repeated measures comparative design.
Study sample: ECAP data were collected from 81 pediatric subjects (41 females and 40 males).
Results: The average ECAP threshold measurement time for the Custom Sound system was 6.2 minutes (SD = 1.0) versus 4.8 minutes (SD = 0.7) for the CR120 device. ECAP thresholds measured with Custom Sound and the CR120 device had an average Pearson product-moment correlation coefficient for all electrodes (N = 1724) of 0.92, p < 0.01; an average mean absolute difference of 6 CLs (SD = 6); and a 95% confidence interval of - 1 to 1 CLs. The test-retest results for Custom Sound and the CR120 device are also included.
Conclusion: A significant reduction in the measurement time for ECAP thresholds was noted with the CR120 device. Furthermore, ECAP thresholds measured with the CR120 device are equivalent to Custom Sound within a clinically acceptable range.
Keywords: Cochlear implant; compound action potential; electrically evoked; electrode; impedance; threshold.