title: A systematic comparison of two pulse sequences for edema assessment in MR-mammography.
abstract: OBJECTIVE
  Perifocal edema, defined as high T2w signal intensity around an enhancing lesion has been described as a specific feature of malignancy. In clinical MR-mammography (MRM), both fatsat and non-fatsat T2w sequences are available. However, there is no consensus on which technique should be used for edema assessment. Consequently, this investigation was performed to compare two commonly used pulse sequences for edema assessment in MRM.
  
  
  METHODS
  321 consecutive patients from a 22 month period were included in this investigation. Further selection criteria were histopathological verification of enhancing lesions and absence of presurgical chemotherapy or biopsy, resulting in 108 malignant and 107 benign lesions. All underwent MRM according to international guidelines including a non-fatsat T2w-TSE sequence (TR/TE: 8900/207 ms) and a short tau inversion recovery fatsat sequence (STIR, TR/TE: 8420/70 ms). All images were acquired in the same orientation (axial) and slice thickness. Two experienced radiologists in consensus rated presence of perifocal edema according to an ordinal scale: 0 = not present, 1 = little, 2 = intermediate, and 3 = distinct. Data analysis was performed using crosstabs and Visual Grading Characteristics (VGC) analysis.
  
  
  RESULTS
  Overall sensitivity/specificity was calculated with 53.7%/94.4% (T2w-TSE) and 52.8%/95.3% (STIR). VGC revealed an area under the VGC curve of 0.502 (standard error 0.026), P = 0.814.
  
  
  CONCLUSIONS
  Perifocal edema is a specific feature of malignancy with moderate sensitivity. VGC analysis did not reveal significant differences between both pulse sequences analysed. Consequently, both T2w-TSE and STIR images are suitable for assessment of perifocal edema.
authors.affiliation: Institute of Diagnostic and Interventional Radiology, Friedrich-Schiller-University Jena, Erlanger Allee 101, D-07740 Jena, Germany. pascal.baltzer@med.uni-jena.de
authors.forename: P A T
authors.initials: PA
authors.lastname: Baltzer
authors.forename: M
authors.initials: M
authors.lastname: Dietzel
authors.lastname: Gajda
authors.forename: O
authors.initials: O
authors.lastname: Camara
authors.forename: W A
authors.initials: WA
authors.lastname: Kaiser
mesh_terms: D019540:Area Under Curve; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000473:pathology; D003287:Contrast Media; D004487:Edema / Q000175:diagnosis*; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008327:Mammography; D008875:Middle Aged; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA