title: Intraosseous hibernoma: a case report and review of the literature.
abstract: METHODS
  A case report and a literature review are presented.
  
  
  OBJECTIVE
  To describe and review the clinical presentation and characteristic imaging and pathology findings of intraosseous hibernoma.
  
  
  BACKGROUND
  Hibernomas are lesions of brown fat. Brown fat is typically found in newborn mammals and is rich in mitochondria, thus enabling its role in thermoregulation. It represents a small proportion of adult fat and is distinct from the more common "white fat." Rarely does a hibernoma occur within bone. To the authors' knowledge, 5 cases in all have been reported in the literature.
  
  
  METHODS
  We report the first case to our knowledge of an intraosseous hibernoma occurring within the lumbar spine as well as a review of the literature.
  
  
  RESULTS
  Characteristic findings from magnetic resonance studies include variable T1W signal relative to skeletal muscle and hyperintense signal on fluid-sensitive imaging. Computed tomography has consistently demonstrated a sclerotic lesion with variable definition. Pathologic findings include sheets of multivacuolated cells with centrally placed nuclei and numerous tiny surrounding cytoplasmic vacuoles overlying bony trabeculae.
  
  
  CONCLUSIONS
  Our review of the literature demonstrates that intraosseous hibernoma is most likely an incidental finding with a predilection for the lower extremities in middle-aged females.
  
  
  METHODS
  4.
authors.affiliation: *Maimonides Medical Center, Brooklyn, NY; and †National Institute for People With Disabilities, New York, NY.
authors.forename: Imran
authors.initials: I
authors.lastname: Hafeez
authors.forename: Steven
authors.initials: S
authors.lastname: Shankman
authors.forename: Jon
authors.initials: J
authors.lastname: Michnovicz
authors.forename: Vincent J
authors.initials: VJ
authors.lastname: Vigorita
mesh_terms: D002001:Adipose Tissue, Brown / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D000368:Aged; D005260:Female; D006801:Humans; D008067:Lipoma; D008161:Lumbosacral Region / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D011859:Radiography; D013125:Spinal Neoplasms