title: Dynamic updating atlas for heart segmentation with a nonlinear field-based model.
abstract: BACKGROUND
  Segmentation of cardiac computed tomography (CT) images is an effective method for assessing the dynamic function of the heart and lungs. In the atlas-based heart segmentation approach, the quality of segmentation usually relies upon atlas images, and the selection of those reference images is a key step. The optimal goal in this selection process is to have the reference images as close to the target image as possible.
  
  
  METHODS
  This study proposes an atlas dynamic update algorithm using a scheme of nonlinear deformation field. The proposed method is based on the features among double-source CT (DSCT) slices. The extraction of these features will form a base to construct an average model and the created reference atlas image is updated during the registration process. A nonlinear field-based model was used to effectively implement a 4D cardiac segmentation.
  
  
  RESULTS
  The proposed segmentation framework was validated with 14 4D cardiac CT sequences. The algorithm achieved an acceptable accuracy (1.0-2.8 mm).
  
  
  CONCLUSIONS
  Our proposed method that combines a nonlinear field-based model and dynamic updating atlas strategies can provide an effective and accurate way for whole heart segmentation. The success of the proposed method largely relies on the effective use of the prior knowledge of the atlas and the similarity explored among the to-be-segmented DSCT sequences.
authors.affiliation: School of Information Science and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou, 510225, China.
authors.forename: Ken
authors.initials: K
authors.lastname: Cai
authors.affiliation: Department of Biomedical Engineering, South China University of Technology, Guangzhou, 510006, China.
authors.forename: Rongqian
authors.initials: R
authors.lastname: Yang
authors.affiliation: School of Information Engineering, Wuyi University, Jiangmen, 529020, China.
authors.forename: Hongwei
authors.initials: H
authors.lastname: Yue
authors.affiliation: Department of Biomedical Engineering, South China University of Technology, Guangzhou, 510006, China.
authors.forename: Lihua
authors.initials: L
authors.lastname: Li
authors.affiliation: Department of Radiology, General Hospital of Guangzhou Military Command of PLA, Guangzhou, 510010, China.
authors.forename: Shanxing
authors.initials: S
authors.lastname: Ou
authors.affiliation: School of Information Technology and Electrical Engineering, the University of Queensland, Brisbane, QLD 4072, Australia.
authors.forename: Feng
authors.initials: F
authors.lastname: Liu
mesh_terms: D000465:Algorithms; D001271:Atlases as Topic; D056973:Four-Dimensional Computed Tomography / Q000379:methods* / Q000706:statistics & numerical data; D006321:Heart / Q000000981:diagnostic imaging* / Q000502:physiology; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008953:Models, Anatomic; D008955:Models, Cardiovascular; D017711:Nonlinear Dynamics
keywords: DSCT; atlas; dynamic; field-based model; heart segmentation; nonlinear