Tip Fold-over in Cochlear Implantation: Case Series.

Tip Fold-over in Cochlear Implantation: Case Series.

Otol Neurotol. 2016 Dec 01;

Authors: Zuniga MG, Rivas A, Hedley-Williams A, Gifford RH, Dwyer R, Dawant BM, Sunderhaus LW, Hovis KL, Wanna GB, Noble JH, Labadie RF

Abstract
OBJECTIVE: To describe the incidence, clinical presentation, and performance of cochlear implant (CI) recipients with tip fold-over.
STUDY DESIGN: Retrospective case series.
SETTING: Tertiary referral center.
PATIENTS: CI recipients who underwent postoperative computed tomography (CT) scanning.
INTERVENTION(S): Tip fold-over was identified tomographically using previously validated software that identifies the electrode array. Electrophysiologic testing including spread of excitation or electric field imaging (EFI) was measured on those with fold-over.
MAIN OUTCOME MEASURE(S): Location of the fold-over; audiological performance pre and postselective deactivation of fold-over electrodes.
RESULTS: Three hundred three ears of 235 CI recipients had postoperative CTs available for review. Six (1.98%) had tip fold-over with 5/6 right-sided ears. Tip fold-over occurred predominantly at 270 degrees and was associated with precurved electrodes (5/6). Patients did not report audiological complaints during initial activation. In one patient, the electrode array remained within the scala tympani with preserved residual hearing despite the fold-over. Spread of excitation supported tip fold-over, but the predictive value was not clear. EFI predicted location of the fold-over with clear predictive value in one patient. At an average follow-up of 11 months, three subjects underwent deactivation of the overlapping electrodes with two of them showing marked audiological improvement.
CONCLUSION: In a large academic center with experienced surgeons, tip fold-over occurred at a rate of 1.98% but was not immediately identifiable clinically. CT imaging definitively showed tip fold-over. Deactivating involved electrodes may improve performance possibly avoiding revision surgery. EFI may be highly predictive of tip fold-over and can be run intraoperatively, potentially obviating the need for intraop fluoroscopy.

PMID: 27918363 [PubMed - as supplied by publisher]

http://ift.tt/2gLnDfU


http://ift.tt/2h1FMUH