title: Silicone allergy: A new cause for cochlear implant extrusion and its management.
abstract: OBJECTIVE
  We introduce silicone allergy as a rare cause for cochlear implant extrusion and discuss its management.
  
  
  METHODS
  Retrospective case series and literature review.
  
  
  METHODS
  Tertiary referral centers.
  
  
  METHODS
  Primary eligibility criteria included patients who experienced a delayed extrusion of their cochlear implants with negative wound cultures and had a suspected or a test-proven allergy to silicone components of an implant.
  
  
  METHODS
  Silicone allergy testing, explantation of a cochlear implant containing allergenic silicone materials, reimplantation with a custom-made cochlear implant excluding an allergenic silicone component.
  
  
  METHODS
  Uneventful wound healing and extrusion-free long-term follow-up after the reimplantation with a custom-made cochlear implant excluding an allergenic silicone component.
  
  
  RESULTS
  Three known cases of cochlear implant extrusion as a result of silicone allergy have been noted from 1991 through 2004 in three cochlear implant programs in the United States. All three devices extruded, resulting in explantation of the old device and reimplantation with a new custom-made device eliminating the allergenic silicone component. Wound cultures were negative in all cases. All three patients experienced a delayed extrusion of their devices. Two of these patients had a test-proven allergy to the implant's silicone components, whereas the third patient was presumed to have a hypersensitivity solely on the basis of a clinical presentation.
  
  
  CONCLUSIONS
  We propose that silicone allergy is a rare cause of cochlear implant extrusion. Patients experiencing cochlear implant extrusion, particularly with a delayed onset and negative wound culture results, should be tested for silicone allergy.
authors.affiliation: California Ear Institute, E. Palo Alto, California, USA. lkunda@calear.com
authors.forename: Larisa D
authors.initials: LD
authors.lastname: Kunda
authors.forename: Katrina R
authors.initials: KR
authors.lastname: Stidham
authors.forename: Michelle M
authors.initials: MM
authors.lastname: Inserra
authors.forename: Peter S
authors.initials: PS
authors.lastname: Roland
authors.forename: Daniel
authors.initials: D
authors.lastname: Franklin
authors.forename: Joseph B
authors.initials: JB
authors.lastname: Roberson
mesh_terms: D002675:Child, Preschool; D019929:Cochlear Implantation; D003054:Cochlear Implants; D003638:Deafness / Q000601:surgery; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000209:etiology / Q000503:physiopathology*; D007223:Infant; D007428:Intradermal Tests; D008297:Male; D011475:Prosthesis Failure; D012086:Reoperation; D012189:Retrospective Studies; D012828:Silicones / Q000009:adverse effects*
chemical_list: D012828:Silicones