title: Erdheim-Chester disease versus multifocal fibrosis and Ormond's disease: a diagnostic dilemma.
abstract: OBJECTIVE
  The aim of the study was to evaluate the effectiveness of different imaging techniques with respect to diagnosis and differential diagnosis between Erdheim-Chester disease (ECD) and multifocal fibrosis (MF)/Ormond's disease (OD).
  
  
  METHODS
  Three cases of ECD were included, two of which were misdiagnosed as MF/OD. Findings in different imaging techniques [plain radiography, skeletal scintigraphy, computed tomography (CT) and magnetic resonance imaging (MRI)] of the lower extremities, chest MRI, craniofacial MRI, abdominal CT and MRI) were compared and ranked with regard to diagnostic efficacy.
  
  
  RESULTS
  Differentiation between ECD and MF/OD is only possible by imaging the long bones. Bone roentgenograms and skeletal scintigraphy, followed by MRI and CT of the lower extremities are the most effective imaging techniques.
  
  
  CONCLUSIONS
  A low threshold for carrying out plain radiography of the lower limbs in case of RF/MF will increase the number of ECD-cases.
authors.affiliation: Department of Radiology, University of Cologne, Cologne, Germany. cbangard@gmx.de
authors.forename: C
authors.initials: C
authors.lastname: Bangard
authors.forename: J
authors.initials: J
authors.lastname: Lotz
authors.forename: H
authors.initials: H
authors.lastname: Rosenthal
authors.forename: M
authors.initials: M
authors.lastname: Galanski
mesh_terms: D001842:Bone and Bones / Q000000981:diagnostic imaging; D003937:Diagnosis, Differential; D031249:Erdheim-Chester Disease / Q000175:diagnosis* / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D007866:Leg; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging; D012185:Retroperitoneal Fibrosis / Q000175:diagnosis* / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed / Q000379:methods