title: A hybrid approach to reducing computed tomography metal artifacts in intracavitary brachytherapy.
abstract: OBJECTIVE
  To develop a hybrid approach to reduce computed tomography (CT) metal artifacts caused by the Fletcher-Suit applicator.
  
  
  METHODS
  Using the acquired raw projection data, the hybrid algorithm determines the separate contributions from the metal and non-metal objects. Next, reconstructions of metal and non-metal images are separately obtained from their estimated projections. A final image is formed by appropriately combining the individual images. Phantom and patient data are used to evaluate the performance of this method.
  
  
  RESULTS
  CT images reconstructed by use of the standard filtered-backprojection (FBP) algorithm contain significant artifacts even for small metal objects. However, images reconstructed using the hybrid algorithm contain virtually no artifacts. For metal objects with complex structures, the hybrid algorithm can also yield images containing fewer severe streak artifacts than those reconstructed using the FBP algorithm alone.
  
  
  CONCLUSIONS
  These studies demonstrate that the hybrid approach can effectively reduce CT metal artifacts caused by the Fletcher-Suit applicator.
authors.affiliation: Department of Radiology, The University of Chicago, Chicago, IL.
authors.forename: Dan
authors.initials: D
authors.lastname: Xia
authors.forename: John C
authors.initials: JC
authors.lastname: Roeske
authors.forename: Lifeng
authors.initials: L
authors.lastname: Yu
authors.forename: Charles A
authors.initials: CA
authors.lastname: Pelizzari
authors.forename: Arno J
authors.initials: AJ
authors.lastname: Mundt
authors.forename: Xiaochuan
authors.initials: X
authors.lastname: Pan
mesh_terms: D000465:Algorithms; D016477:Artifacts; D001918:Brachytherapy / Q000379:methods*; D008670:Metals; D019047:Phantoms, Imaging; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D008670:Metals