title: Evaluation of tomosynthesis elastography in a breast-mimicking phantom.
abstract: OBJECTIVE
  To evaluate whether measurement of strain under static compression in tomosynthesis of a breast-mimicking phantom can be used to distinguish tumor-simulating lesions of different elasticities and to compare the results to values predicted by rheometric analysis as well as results of ultrasound elastography.
  
  
  METHODS
  We prepared three soft breast-mimicking phantoms containing simulated tumors of different elasticities. The phantoms were imaged using a wide angle tomosynthesis system with increasing compression settings ranging from 0 N to 105 N in steps of 15 N. Strain of the inclusions was measured in two planes using a commercially available mammography workstation. The elasticity of the phantom matrix and inclusion material was determined by rheometric analysis. Ultrasound elastography of the inclusions was performed using two different ultrasound elastography algorithms.
  
  
  RESULTS
  Strain at maximal compression was 24.4%/24.5% in plane 1/plane 2, respectively, for the soft inclusion, 19.6%/16.9% for the intermediate inclusion, and 6.0%/10.2% for the firm inclusion. The strain ratios predicted by rheometrical testing were 0.41, 0.83 and 1.26 for the soft, intermediate, and firm inclusions, respectively. The strain ratios obtained for the soft, intermediate, and firm inclusions were 0.72±0.13, 1.02±0.21 and 2.67±1.70, respectively for tomosynthesis elastography, 0.91, 1.64 and 2.07, respectively, for ultrasound tissue strain imaging, and 0.97, 2.06 and 2.37, respectively, for ultrasound real-time elastography.
  
  
  CONCLUSIONS
  Differentiation of tumor-simulating inclusions by elasticity in a breast mimicking phantom may be possible by measuring strain in tomosynthesis. This method may be useful for assessing elasticity of breast lesions tomosynthesis of the breast.
authors: Department of Radiology, Charité Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany. florian.engelken@charite.de
authors: Florian Jan
authors: FJ
authors: Engelken
authors: Ingolf
authors: I
authors: Sack
authors: Dieter
authors: D
authors: Klatt
authors: Thomas
authors: T
authors: Fischer
authors: Eva Maria
authors: EM
authors: Fallenberg
authors: Ulrich
authors: U
authors: Bick
authors: Felix
authors: F
authors: Diekmann
mesh_terms: D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques / Q000295:instrumentation* / Q000379:methods*; D005260:Female; D006801:Humans; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016217:Ultrasonography, Mammary / Q000295:instrumentation* / Q000379:methods*