title: Residual speech perception and cochlear implant performance in postlingually deafened adults.
abstract: OBJECTIVE
  This study aimed at testing the post-hoc validity of the previously reported predictive index for postoperative cochlear implant performance, based on preoperative duration of deafness, and speech reception.
  
  
  METHODS
  Adult patients with postlingual severe to profound hearing loss, who were implanted with Cochlear Corporation CI-22 and CI-24 devices were included in this study. We studied the relationship between their postoperative word recognition scores and preoperative factors, namely, duration of deafness, and sentence recognition. We used the same predictive index reported in the previous study to predict their postoperative scores and test the model's agreement with the actual performance.
  
  
  RESULTS
  We found that postoperative performance as measured by CNC word scores had an inverse relationship with the duration of deafness, and a direct correlation with the preoperative performance on CID sentence recognition tests. A nonlinear term [Duration / (1+CID)] was shown to improve the correlation coefficient of our predictive index.
  
  
  CONCLUSIONS
  Some predictability of cochlear implant outcome is possible depending on the preoperative duration of deafness and speech recognition abilities. Preoperative residual speech recognition acts as a "trophic factor" that protects the spiral ganglion and/ or the central auditory pathways from degeneration. In other words, it improves the expected postoperative word scores.
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, University of Iowa, Iowa City 52242, USA.
authors.forename: Nahla A
authors.initials: NA
authors.lastname: Gomaa
authors.forename: Jay T
authors.initials: JT
authors.lastname: Rubinstein
authors.forename: Mary W
authors.initials: MW
authors.lastname: Lowder
authors.forename: Richard S
authors.initials: RS
authors.lastname: Tyler
authors.forename: Bruce J
authors.initials: BJ
authors.lastname: Gantz
mesh_terms: D019929:Cochlear Implantation / Q000295:instrumentation*; D015331:Cohort Studies; D005260:Female; D034381:Hearing Loss / Q000601:surgery*; D006801:Humans; D008297:Male; D013063:Speech Discrimination Tests; D013067:Speech Perception; D013997:Time Factors; D016896:Treatment Outcome