title: [The magnetic resonance tomography of Ewing's sarcomas: the morphology and tumor extension].
abstract: OBJECTIVE
  The morphology and delineation of Ewing sarcoma in magnetic resonance imaging was investigated.
  
  
  METHODS
  Magnetic resonance images (spin-echo techniques; T1-w pre/post gadolinium, T2-w) of 59 patients as part of a multicenter study were evaluated retrospectively. Qualitative image analysis was performed: signal intensity (point of reference extraosseous: muscle, intraosseous: bone marrow), enhancement patterns, lesion delineation and differentiation between tumor and oedema.
  
  
  RESULTS
  Signal intensity: T1-w: extraosseous: 75% isointense, intraosseous: 92% hypointense; T2-w extraosseous: 100% hyperintense, intraosseous: 93% hyperintense. Enhancement pattern: 97% both extra- and intraosseous. Best delineation intraosseous in T1-w (53% good, 36% very good), extraosseous in gadolinium enhanced T1-w (46% good, 37% very good) and T2-w (55% good, 33% very good). Differentiation between tumour and oedema was intraosseous not possible, extraosseous in T2-w in 61%.
  
  
  CONCLUSIONS
  Morphology of Ewing sarcoma in magnetic resonance imaging is rather uniform. The lesion is intra- and extraosseous sharply delineated, though tumour and oedema can be rarely differentiated.
authors.affiliation: Institut für Klinische Radiologie, Westfälische Wilhelms-Universität Münster.
authors.forename: M D
authors.initials: MD
authors.lastname: Häussler
authors.forename: T
authors.initials: T
authors.lastname: Vestring
authors.forename: B
authors.initials: B
authors.lastname: Steinhoff
authors.forename: M
authors.initials: M
authors.lastname: Paulussen
authors.forename: T
authors.initials: T
authors.lastname: Lange
authors.forename: C
authors.initials: C
authors.lastname: Hoffmann
authors.forename: H F
authors.initials: HF
authors.lastname: Jürgens
authors.forename: P E
authors.initials: PE
authors.lastname: Peters
mesh_terms: D000293:Adolescent; D000328:Adult; D001859:Bone Neoplasms / Q000175:diagnosis* / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D005060:Europe; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods / Q000706:statistics & numerical data; D008297:Male; D009361:Neoplasm Invasiveness; D012189:Retrospective Studies; D012512:Sarcoma, Ewing / Q000175:diagnosis* / Q000473:pathology; D013997:Time Factors
vernacular_title: Magnetresonanztomographie von Ewing-Sarkomen: Morphologie und Tumorausdehnung.