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Development of cholesterol granuloma in a temporal bone petrous apex previously containing marrow exposed to air

Yamil Selman1, John W Wood, Fred F Telischi

  • 1University of Virginia School of Medicine, Charlottesville, Virginia, USA.

Otology & Neurotology : Official Publication of the American Otological Society, American Neurotology Society [And] European Academy of Otology and Neurotology
|June 7, 2013
PubMed
Abstract

Insights

Cholesterol granulomas in the temporal bone may form when bone marrow is exposed to air cells. This case study supports the exposed marrow hypothesis for petrous apex cholesterol granuloma development.

Area of Science:

  • Otolaryngology
  • Pathology
  • Radiology

Background:

  • Cholesterol granuloma formation in the temporal bone is not fully understood.
  • The exposed marrow hypothesis suggests a role for medullary bone in pathogenesis.

Observation:

  • A patient developed a new cholesterol granuloma in the petrous apex.
  • The affected area was hyperpneumatized with exposed medullary bone.

Findings:

  • The development of a contralateral cholesterol granuloma was observed.
  • This occurred in a hyperpneumatized petrous apex with exposed medullary bone.

Implications:

  • The medullary-air cell interface may drive petrous apex cholesterol granuloma formation.
  • This finding supports the exposed marrow hypothesis for cholesterol granuloma pathogenesis.

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