title: Hearing preservation after complete cochlear coverage in cochlear implantation with the free-fitting FLEXSOFT electrode carrier.
abstract: OBJECTIVE
  To demonstrate the possibility of atraumatic insertion with the free-fitting FLEX electrode by evaluating the degree of hearing preservation postoperatively.
  
  
  METHODS
  Retrospective study.
  
  
  METHODS
  Academic tertiary care center.
  
  
  METHODS
  Twenty-two severely to profoundly hearing impaired subjects with measurable residual hearing preoperatively.
  
  
  METHODS
  Atraumatic implantation with the 31.5-mm-long, free-fitting, and highly flexible FLEX electrode using either the round window approach or a cochleostomy technique.
  
  
  METHODS
  Subjects were tested preoperatively in unaided condition and at varying intervals postoperatively. Preoperative and postoperative low-frequency pure-tone average (PTA) and PTA shifts were calculated. Speech perception was measured preoperatively and postoperatively using the Freiburger monosyllabic word test in quiet.
  
  
  RESULTS
  Preoperative low-frequency hearing could be preserved to a certain degree in 77.3% of subjects (17/22) after insertion of the FLEX electrode up to the point of first resistance. Complete loss of residual hearing was observed in 22.7% of subjects (5/22). In 18.2% of the subjects (4/22), the preoperative PTA was preserved within 10 dB. Pure-tone average results between preoperative and most recent testing showed statistically significant differences (p < 0.001 to p = 0.031) for almost all loudness levels ranging from 125 Hz to 1.5 kHz. The maximum threshold shift was 40 dB at 250 Hz for the lower frequencies up to 1 kHz. Monosyllable testing in quiet demonstrated significant improvement over time (p < 0.001).
  
  
  CONCLUSIONS
  This study showed that preservation of residual hearing is possible in a high number of subjects when a flexible electrode and atraumatic surgical techniques are used.
authors: Department of Otorhinolaryngology, Goethe University, Frankfurt, Germany. silke.helbig@kgu.de
authors: Silke
authors: S
authors: Helbig
authors: Uwe
authors: U
authors: Baumann
authors: Constanze
authors: C
authors: Hey
authors: Matthias
authors: M
authors: Helbig
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001301:Audiometry, Pure-Tone; D001309:Auditory Threshold / Q000502:physiology*; D019929:Cochlear Implantation; D005260:Female; D034381:Hearing Loss / Q000534:rehabilitation*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013067:Speech Perception / Q000502:physiology*; D016896:Treatment Outcome