Cochlear Implant Device Failure Secondary to Cholesterol Granuloma–Mediated Cochlear Erosion

Study Design Case report. Setting A tertiary care pediatric hospital. Patient 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. Intervention 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. Conclusion 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.

[1]  A. Charpiot,et al.  Characteristics of 629 Vestibular Schwannomas According to Preoperative Caloric Responses , 2010, Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology.

[2]  J. Nadol,et al.  Foreign Body or Hypersensitivity Granuloma of the Inner Ear After Cochlear Implantation: One Possible Cause of a Soft Failure? , 2008, Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology.

[3]  P. Roland,et al.  Lesions of the petrous apex: diagnosis and management. , 2007, Otolaryngologic clinics of North America.

[4]  S. Chavda,et al.  A large and uncharacteristically aggressive cholesterol granuloma of the middle ear , 2005, The Journal of Laryngology & Otology.

[5]  E. Murugasu,et al.  Invasive Middle Ear Cholesterol Granuloma Involving the Basal Turn of the Cochlea With Profound Sensorineural Hearing Loss , 2004, Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology.

[6]  R. Jackler,et al.  A New Theory to Explain the Genesis of Petrous Apex Cholesterol Granuloma , 2003, Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology.

[7]  S. Cheung,et al.  Subcochlear Petrous Cholesterol Granuloma Involving the Infratemporal Fossa , 1998, Otolaryngology--head and neck surgery : official journal of American Academy of Otolaryngology-Head and Neck Surgery.

[8]  C. Morales Angulo,et al.  [Cholesterol granuloma of the petrous apex]. , 1994, Acta otorrinolaringologica espanola.

[9]  G. Nager,et al.  Cholesterol Granuloma Involving the Temporal Bone , 1976, The Annals of otology, rhinology, and laryngology.