title: Contrast-enhanced dual energy mammography with a novel anode/filter combination and artifact reduction: a feasibility study.
abstract: OBJECTIVE
  To demonstrate the feasibility of contrast-enhanced dual-energy mammography (CEDEM) using titanium (Ti) filtering at 49 kVp for high-energy images and a novel artefact reducing image-subtraction post-processing algorithm.
  
  
  METHODS
  Fifteen patients with suspicious findings (ACR BI-RADS 4 and 5) detected with digital mammography (MG) that required biopsy were included. CEDEM examinations were performed on a modified prototype machine. Acquired HE and low-energy raw data images were registered non-rigidly to compensate for possible subtle tissue motion. Subtracted CEDEM images were generated via weighted subtraction, using a fully automatic, locally adjusted tissue thickness-dependent subtraction factor to avoid over-subtraction at the breast border. Two observers evaluated the MG and CEDEM images according to ACR BI-RADS in two reading sessions. Results were correlated with histopathology.
  
  
  RESULTS
  Seven patients with benign and eight with malignant findings were included. All malignant lesions showed a strong contrast enhancement. BI-RADS assessment was altered in 66.6 % through the addition of CEDEM, resulting in increased overall accuracy. With CEDEM, additional lesions were depicted and false-positive rate was reduced compared to MG.
  
  
  CONCLUSIONS
  CEDEM using Ti filtering with 49 kVp for HE exposures is feasible in a clinical setting. The proposed image-processing algorithm has the potential to reduce artefacts and improve CEDEM images.
  
  
  CONCLUSIONS
  • CEDEM with a titanium filter is feasible in a clinical setting. • Breast thickness-dependent image subtraction has the potential to improve CEDEM images. • The proposed image-processing algorithm reduces artefacts.
authors.affiliation: Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria. thomas.helbich@meduniwien.ac.at.|Division of Molecular and Gender Imaging, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria. thomas.helbich@meduniwien.ac.at.
authors.forename: Thomas
authors.initials: T
authors.lastname: Knogler
authors.affiliation: Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
authors.forename: Peter
authors.initials: P
authors.lastname: Homolka
authors.affiliation: Siemens AG, Healthcare, X-Ray Products, Allee am Röthelheimpark 2, 91052, Erlangen, Germany.
authors.forename: Mathias
authors.initials: M
authors.lastname: Hörnig
authors.affiliation: Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
authors.forename: Robert
authors.initials: R
authors.lastname: Leithner
authors.affiliation: Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.|Computational Imaging Research Laboratory, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
authors.forename: Georg
authors.initials: G
authors.lastname: Langs
authors.affiliation: Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.|Computational Imaging Research Laboratory, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
authors.forename: Martin
authors.initials: M
authors.lastname: Waitzbauer
authors.affiliation: Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.|Division of Molecular and Gender Imaging, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
authors.forename: Katja
authors.initials: K
authors.lastname: Pinker-Domenig
authors.affiliation: Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.|Division of Molecular and Gender Imaging, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
authors.forename: Sabine
authors.initials: S
authors.lastname: Leitner
authors.affiliation: Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.|Division of Molecular and Gender Imaging, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
authors.forename: Thomas H
authors.initials: TH
authors.lastname: Helbich
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D016477:Artifacts; D001940:Breast / Q000000981:diagnostic imaging; D001943:Breast Neoplasms / Q000000981:diagnostic imaging*; D018270:Carcinoma, Ductal, Breast / Q000000981:diagnostic imaging*; D003287:Contrast Media; D004566:Electrodes; D005240:Feasibility Studies; D005260:Female; D018226:Fibroadenoma; D005348:Fibrocystic Breast Disease / Q000000981:diagnostic imaging*; D006099:Granuloma / Q000000981:diagnostic imaging*; D006801:Humans; D007089:Image Enhancement; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008327:Mammography / Q000379:methods; D008875:Middle Aged; D018300:Papilloma, Intraductal / Q000000981:diagnostic imaging*; D011856:Radiographic Image Enhancement / Q000379:methods*; D059629:Signal-To-Noise Ratio
chemical_list: D003287:Contrast Media
keywords: Breast cancer; Contrast agent; Contrast-enhanced digital mammography; Digital mammography; Image processing