title: Non-rigid registration of serial dedicated breast CT, longitudinal dedicated breast CT and PET/CT images using the diffeomorphic demons method.
abstract: OBJECTIVE
  Dedicated breast CT and PET/CT scanners provide detailed 3D anatomical and functional imaging data sets and are currently being investigated for applications in breast cancer management such as diagnosis, monitoring response to therapy and radiation therapy planning. Our objective was to evaluate the performance of the diffeomorphic demons (DD) non-rigid image registration method to spatially align 3D serial (pre- and post-contrast) dedicated breast computed tomography (CT), and longitudinally-acquired dedicated 3D breast CT and positron emission tomography (PET)/CT images.
  
  
  METHODS
  The algorithmic parameters of the DD method were optimized for the alignment of dedicated breast CT images using training data and fixed. The performance of the method for image alignment was quantitatively evaluated using three separate data sets; (1) serial breast CT pre- and post-contrast images of 20 women, (2) breast CT images of 20 women acquired before and after repositioning the subject on the scanner, and (3) dedicated breast PET/CT images of 7 women undergoing neo-adjuvant chemotherapy acquired pre-treatment and after 1 cycle of therapy.
  
  
  RESULTS
  The DD registration method outperformed no registration (p < 0.001) and conventional affine registration (p ≤ 0.002) for serial and longitudinal breast CT and PET/CT image alignment. In spite of the large size of the imaging data, the computational cost of the DD method was found to be reasonable (3-5 min).
  
  
  CONCLUSIONS
  Co-registration of dedicated breast CT and PET/CT images can be performed rapidly and reliably using the DD method. This is the first study evaluating the DD registration method for the alignment of dedicated breast CT and PET/CT images.
authors.affiliation: Department of Radiology, University of California-Davis School of Medicine, Sacramento, CA 95817, USA.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Santos
authors.affiliation: Department of Radiology, University of California-Davis School of Medicine, Sacramento, CA 95817, USA. Electronic address: ajchaudhari@ucdavis.edu.
authors.forename: Abhijit J
authors.initials: AJ
authors.lastname: Chaudhari
authors.affiliation: Signal and Image Processing Institute, University of Southern California, Los Angeles, CA 90089, USA.
authors.forename: Anand A
authors.initials: AA
authors.lastname: Joshi
authors.affiliation: Department of Biomedical Engineering, University of California-Davis, Davis, CA 95616, USA.
authors.forename: Andrea
authors.initials: A
authors.lastname: Ferrero
authors.affiliation: Department of Radiology, University of California-Davis School of Medicine, Sacramento, CA 95817, USA.
authors.forename: Kai
authors.initials: K
authors.lastname: Yang
authors.affiliation: Department of Radiology, University of California-Davis School of Medicine, Sacramento, CA 95817, USA; Department of Biomedical Engineering, University of California-Davis, Davis, CA 95616, USA.
authors.forename: John M
authors.initials: JM
authors.lastname: Boone
authors.affiliation: Department of Radiology, University of California-Davis School of Medicine, Sacramento, CA 95817, USA; Department of Biomedical Engineering, University of California-Davis, Davis, CA 95616, USA.
authors.forename: Ramsey D
authors.initials: RD
authors.lastname: Badawi
mesh_terms: D000465:Algorithms; D001940:Breast / Q000000981:diagnostic imaging*; D001943:Breast Neoplasms / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008327:Mammography / Q000379:methods*; D049268:Positron-Emission Tomography / Q000379:methods*; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*
keywords: Breast PET/CT; Dedicated breast CT; Diffeomorphic demons; Non-rigid registration