Simultaneous Analog Stimulation (SAS)--Continuous Interleaved Sampler (CIS) pilot comparison study in Europe

Abstract

The recent availability of the enhanced bipolar electrode array in the CLARION Multi-Strategy Cochlear Implant has permitted clinicians to fit patients successfully with the Simultaneous Analog Stimulation (SAS) strategy by means of bipolar coupling. Out of 22 consecutively implanted subjects, 20 subjects could be fitted with both Continuous Interleaved Sampler (CIS) and SAS strategies. Their performance was evaluated up to 3 months postoperatively. Speech perception results, as well as the patient's preference for either CIS or SAS, were examined. It was found that half of the subjects selected SAS as their preferred strategy and that the use of a preferred strategy resulted in higher overall patient performance. Further analyses showed that those subjects preferring SAS had higher electrode impedance values and lower threshold and most comfortable loudness levels than subjects preferring CIS. We presume that these psychophysical findings are, in part, related to the position of the intracochlear electrode array. Specifically, SAS users may have a more modiolus-hugging electrode array position.