title: Atraumatic round window deep insertion of cochlear electrodes.
abstract: CONCLUSIONS
  This study shows that by using the round window approach and deep insertion, it is possible to reduce electrode insertion trauma (EIT), as indicated by the results of the hearing preservation marker.
  
  
  OBJECTIVE
  In this prospective study EIT was evaluated in 42 subjects with low frequency hearing before surgery with 28 mm round window deep insertion.
  
  
  METHODS
  The degree of hearing preservation was a marker of EIT. Pure tone audiometry, monosyllable testing was conducted preoperatively and then at 3, 6, and 13 months after surgery.
  
  
  RESULTS
  Immediate hearing preservation (3 months postoperatively) was 92.9% (39/42). The surgery-related hearing preservation 13 months after surgery varied from 85% (34/40) to 90% (36/40). The ipsilateral implanted ear showed significant differences between preoperative and postoperative hearing thresholds (p < 0.005). Comparisons of thresholds for the control ear showed a significant difference between preoperative and postoperative thresholds tested 13 months after surgery (p < 0.05). When the subtraction factor of the mean contralateral hearing loss for each tested frequency for the same time interval was applied to the implanted ear, no significant hearing loss was found, showing that postoperative ipsilateral progressive hearing loss was caused by etiology rather than surgery.
authors.affiliation: Institute of Physiology and Pathology of Hearing, Warsaw, Poland.
authors.forename: Henryk
authors.initials: H
authors.lastname: Skarzynski
authors.forename: Artur
authors.initials: A
authors.lastname: Lorens
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Zgoda
authors.forename: Anna
authors.initials: A
authors.lastname: Piotrowska
authors.forename: Piotr Henryk
authors.initials: PH
authors.lastname: Skarzynski
authors.forename: Agata
authors.initials: A
authors.lastname: Szkielkowska
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D003054:Cochlear Implants; D004567:Electrodes, Implanted; D005260:Female; D005500:Follow-Up Studies; D006309:Hearing / Q000502:physiology; D034381:Hearing Loss / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012405:Round Window, Ear / Q000601:surgery*; D013701:Temporal Bone / Q000601:surgery*; D016896:Treatment Outcome; D055815:Young Adult