title: Inflammatory pseudotumor of the maxillary sinus: CT and MR findings in six cases.
abstract: OBJECTIVE
  Inflammatory pseudotumor is a chronic inflammatory lesion of unknown origin. The purpose of this study was to analyze the CT and MR findings in six cases of inflammatory pseudotumor of the maxillary sinus in order to determine if there were any imaging findings that distinguish this lesion from the more common type of pseudotumor that occurs in the orbit.
  
  
  METHODS
  Six patients with pseudotumor of the maxillary sinus were identified retrospectively. The diagnosis was based on biopsy specimens. Their CT scans and MR images were studied by two radiologists to identify specifically the presence of soft-tissue disease and the presence and type of any bone involvement.
  
  
  RESULTS
  CT and MR images showed some degree of involvement of the bony wall in all cases. All patients had a soft-tissue mass with mild enhancement on CT scans and intermediate signal intensity on both T1- and T2-weighted MR images.
  
  
  CONCLUSIONS
  Our experience shows that inflammatory pseudotumor of the maxillary sinus causes bone changes on CT and MR images, findings that mimic a malignant tumor. Bone involvement appears to be more common in pseudotumor of the maxillary antrum than in its orbital counterpart.
authors.affiliation: Department of Radiology, Mount Sinai School of Medicine, City University of New York, NY 10029.
authors.forename: P M
authors.initials: PM
authors.lastname: Som
authors.forename: M S
authors.initials: MS
authors.lastname: Brandwein
authors.forename: C
authors.initials: C
authors.lastname: Maldjian
authors.forename: A J
authors.initials: AJ
authors.lastname: Reino
authors.forename: W
authors.initials: W
authors.lastname: Lawson
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D006104:Granuloma, Plasma Cell / Q000175:diagnosis* / Q000453:epidemiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008443:Maxillary Sinus / Q000000981:diagnostic imaging / Q000473:pathology*; D008875:Middle Aged; D010254:Paranasal Sinus Diseases / Q000175:diagnosis* / Q000453:epidemiology; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed