title: Evolution of electrode array diameter for hearing preservation in cochlear implantation.
abstract: CONCLUSIONS
  Residual hearing could be preserved with various arrays ranging from 16 to 18 mm in insertion length and 0.25 to 0.5 mm tip diameter. Whether array insertion is performed through a cochleostomy or a round window, tip diameter is an essential criterion for the array design to improve hearing preservation results.
  
  
  OBJECTIVE
  The goal of this study was to report the outcome of patients implanted with electric acoustic cochlear implants with various surgical techniques and array designs.
  
  
  METHODS
  Thirty-two implanted ears (30 patients) were included in this retrospective study. Three array models were inserted: Contour Advance implant (n = 16), Nucleus Hybrid-L (n = 12), and Med-El Flex EAS (n = 4). Postoperative pure tone audiometry was performed at 3 and 12 months after implantation.
  
  
  RESULTS
  Three months postoperatively, hearing preservation within 30 dB was achieved in 50%, 50%, and 84% cases of patients implanted with a Contour Advance, Flex-EAS, and Hybrid-L, respectively. Two patients (Hybrid-L group) had a delayed sudden hearing loss (> 30 dB) 3 months postoperatively and three patients (Contour Advance group) had total hearing loss at 1 year. Best results were achieved using arrays with small tip diameters. Cochleostomy or round window insertion did not affect hearing preservation results.
authors.affiliation: Univ Paris Diderot, Sorbonne Paris Cité, Laboratoire UMR-S 867, Paris, France. yann.nguyen@inserm.fr
authors.forename: Yann
authors.initials: Y
authors.lastname: Nguyen
authors.forename: Isabelle
authors.initials: I
authors.lastname: Mosnier
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Borel
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Ambert-Dahan
authors.forename: Didier
authors.initials: D
authors.lastname: Bouccara
authors.forename: Alexis
authors.initials: A
authors.lastname: Bozorg-Grayeli
authors.forename: Evelyne
authors.initials: E
authors.lastname: Ferrary
authors.forename: Olivier
authors.initials: O
authors.lastname: Sterkers
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001301:Audiometry, Pure-Tone; D001309:Auditory Threshold; D002648:Child; D019929:Cochlear Implantation / Q000379:methods*; D004567:Electrodes, Implanted; D005260:Female; D005500:Follow-Up Studies; D006309:Hearing; D034381:Hearing Loss / Q000503:physiopathology / Q000601:surgery*; D006320:Hearing Tests; D006801:Humans; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design; D012189:Retrospective Studies; D012405:Round Window, Ear / Q000601:surgery*; D016896:Treatment Outcome; D055815:Young Adult