title: Organized hematoma in the paranasal sinus and nasal cavity--imaging diagnosis and pathological findings.
abstract: OBJECTIVE
  The "organized hematoma" is a non-neoplastic, hemorrhagic lesion, which can develop in the paranasal sinus and nasal cavity. This is the first report on the relationship between the imaging and pathological findings.
  
  
  METHODS
  We diagnosed organized hematoma, based on three criteria: no existence of neoplastic cells; consistency of hematoma and fibrosis; and development from the paranasal sinus and nasal cavity. We retrospectively investigated six cases from the patients' medical records.
  
  
  RESULTS
  On the imaging findings, the central part of the lesion was enhanced more strongly than the lesion periphery. All of the pathological findings were hematoma at the center, and fibrosis at the periphery. In three of the cases, dilated vessels were found but not in the other three.
  
  
  CONCLUSIONS
  We found that the biphasic appearance of the imaging findings correlated with that of the pathological findings. There are two pathological types--the dilated vessel type and the non-dilated vessel type.
authors.affiliation: The Department of Otorhinolaryngology, Faculty of Medicine, The University of Tokyo, Tokyo, Japan. goomura@msn.com
authors.forename: Go
authors.initials: G
authors.lastname: Omura
authors.forename: Kenta
authors.initials: K
authors.lastname: Watanabe
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Fujishiro
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Ebihara
authors.forename: Kazunari
authors.initials: K
authors.lastname: Nakao
authors.forename: Takahiro
authors.initials: T
authors.lastname: Asakage
mesh_terms: D000328:Adult; D003937:Diagnosis, Differential; D004724:Endoscopy; D005260:Female; D005355:Fibrosis; D006406:Hematoma / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009296:Nasal Cavity / Q000473:pathology / Q000601:surgery; D015508:Nasal Obstruction / Q000175:diagnosis / Q000473:pathology; D009668:Nose Diseases / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D010254:Paranasal Sinus Diseases / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed