title: Efficacy of a cochlear implant simultaneous analog stimulation strategy coupled with a monopolar electrode configuration.
abstract: OBJECTIVE
  The present study was performed to evaluate the efficacy and clinical feasibility of using monopolar stimulation with the Clarion Simultaneous Analog Stimulation (SAS) strategy in patients with cochlear implants.
  
  
  METHODS
  Speech recognition by 10 Clarion cochlear implant users was evaluated by means of 4 different speech processing strategy/electrode configuration combinations; ie, SAS and Continuous Interleaved Sampling (CIS) strategies were each used with monopolar (MP) and bipolar (BP) electrode configurations. The test measures included consonants, vowels, consonant-nucleus-consonant words, and Hearing in Noise Test sentences with a +10 dB signal-to-noise ratio. Additionally, subjective judgments of sound quality were obtained for each strategy/configuration combination.
  
  
  RESULTS
  All subjects but 1 demonstrated open-set speech recognition with the SAS/MP combination. The group mean Hearing in Noise Test sentence score for the SAS/MP combination was 31.6% (range, 0% to 92%) correct, as compared to 25.0%, 46.7%, and 37.8% correct for the CIS/BP, CIS/MP, and SAS/BP combinations, respectively. Intersubject variability was high, and there were no significant differences in mean speech recognition scores or mean preference ratings among the 4 strategy/configuration combinations tested. Individually, the best speech recognition performance was with the subject's everyday strategy/configuration combination in 72% of the applicable cases. If the everyday strategy was excluded from the analysis, the subjects performed best with the SAS/MP combination in 37.5% of the remaining cases.
  
  
  CONCLUSIONS
  The SAS processing strategy with an MP electrode configuration gave reasonable speech recognition in most subjects, even though subjects had minimal previous experience with this strategy/configuration combination. The SAS/MP combination might be particularly appropriate for patients for whom a full dynamic range of electrical hearing could not be achieved with a BP configuration.
authors.affiliation: Kresge Hearing Research Institute, Department of Otolaryngology, University of Michigan, Ann Arbor, Michigan, USA.
authors.forename: Li
authors.initials: L
authors.lastname: Xu
authors.forename: Teresa A
authors.initials: TA
authors.lastname: Zwolan
authors.forename: Catherine S
authors.initials: CS
authors.lastname: Thompson
authors.forename: Bryan E
authors.initials: BE
authors.lastname: Pfingst
mesh_terms: D000328:Adult; D000368:Aged; D003054:Cochlear Implants; D004558:Electric Stimulation / Q000295:instrumentation; D004566:Electrodes; D004867:Equipment Design; D005240:Feasibility Studies; D006309:Hearing; D006801:Humans; D008875:Middle Aged