title: An active contour method for bone cement reconstruction from C-arm x-ray images.
abstract: A novel algorithm is presented to segment and reconstruct injected bone cement from a sparse set of X-ray images acquired at arbitrary poses. The sparse X-ray multi-view active contour (SxMAC-pronounced "smack") can 1) reconstruct objects for which the background partially occludes the object in X-ray images, 2) use X-ray images acquired on a noncircular trajectory, and 3) incorporate prior computed tomography (CT) information. The algorithm's inputs are preprocessed X-ray images, their associated pose information, and prior CT, if available. The algorithm initiates automated reconstruction using visual hull computation from a sparse number of X-ray images. It then improves the accuracy of the reconstruction by optimizing a geodesic active contour. Experiments with mathematical phantoms demonstrate improvements over a conventional silhouette based approach, and a cadaver experiment demonstrates SxMAC's ability to reconstruct high contrast bone cement that has been injected into a femur and achieve sub-millimeter accuracy with four images.
authors: Department of Computer Science, Johns Hopkins University, Baltimore, MD 21218, USA. blake@cs.jhu.edu
authors: Blake C
authors: BC
authors: Lucas
authors: Yoshito
authors: Y
authors: Otake
authors: Mehran
authors: M
authors: Armand
authors: Russell H
authors: RH
authors: Taylor
mesh_terms: D000465:Algorithms; D001843:Bone Cements; D005269:Femur / Q000000981:diagnostic imaging; D006801:Humans; D008954:Models, Biological; D019047:Phantoms, Imaging; D011856:Radiographic Image Enhancement / Q000379:methods*
chemical_list: D001843:Bone Cements