Cochlear implant device failure secondary to cholesterol granuloma-mediated cochlear erosion.
METHODS
Case report.


METHODS
A tertiary care pediatric hospital.


METHODS
A 7-year-old boy complained of retroauricular pain 3.5 years after cochlear implantation. Temporal bone computed tomographic scan revealed a soft tissue density filling the mastoid and middle ear space. There was extensive osseous erosion involving the cochlear promontory that resulted in lateral displacement electrode array into the middle ear space.


METHODS
Mastoidectomy with removal of cochlear implant.


RESULTS
Pathologic examination of the soft tissue filling the mastoid cavity was consistent with a cholesterol granuloma. The cultures of the mastoid cavity demonstrated no growth. Examination of the explanted device revealed a cell layer covering the length of the electrode. The stylet tract was filled with cells that grew out through the silicone component. No birefringent cholesterol crystals were detected in the tissue surrounding the electrode. Biofilms were not identified.


CONCLUSIONS
The authors describe a unique case of a cholesterol granuloma of the middle ear and mastoid in a cochlear implant recipient causing erosion of the otic capsule and displacement of the cochlear implant electrode array into the middle ear space.
Department of Otolaryngology-Head and Neck Surgery, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9035, USA.
Ryan Eric
RE
Neilan
Karen
K
Pawlowski
Brandon
B
Isaacson
Peter S
PS
Roland
D002648:Child; D002784:Cholesterol; D003051:Cochlea / Q000473:pathology* / Q000601:surgery; D003054:Cochlear Implants; D003638:Deafness / Q000601:surgery; D004868:Equipment Failure; D015745:Granuloma, Foreign-Body / Q000473:pathology* / Q000601:surgery; D006801:Humans; D008297:Male; D008416:Mastoid / Q000473:pathology* / Q000601:surgery; D016896:Treatment Outcome
D002784:Cholesterol