title: Metal Artifact Reduction in Cone-Beam Computed Tomography for Head and Neck Radiotherapy.
abstract: To evaluate a method for reducing metal artifacts, arising from dental fillings, on cone-beam computed tomography images.
  
  
  
  A projection interpolation algorithm is applied to cone-beam computed tomography images containing metal artifacts from dental fillings. This technique involves identifying metal regions in individual cone-beam computed tomography projections and interpolating the surrounding values to remove the metal from the projection data. Axial cone-beam computed tomography images are then reconstructed, resulting in a reduction in the streak artifacts produced by the metal. Both phantom and patient imaging data are used to evaluate this technique.
  
  
  
  The interpolation substitution technique successfully reduced metal artifacts in all cases. Corrected images had fewer or no streak artifacts compared to their noncorrected counterparts. Quantitatively, regions of interest containing the artifacts showed reduced variance in the corrected images versus the uncorrected images. Average pixel values in regions of interest around the metal object were also closer in value to nonmetal regions after artifact reduction. Artifact correction tended to perform better on patient images with less complex metal objects versus those with multiple large dental fillings.
  
  
  
  The interpolation substitution is potentially an efficient and effective technique for reducing metal artifacts caused by dental fillings on cone-beam computed tomography image. This technique may be effective in reducing such artifacts in patients with head and neck cancer receiving daily image-guided radiotherapy.
authors.affiliation: Department of Radiation Oncology, Loyola University Medical Center, Maywood, IL, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Korpics
authors.affiliation: Department of Radiation Oncology, Loyola University Medical Center, Maywood, IL, USA.
authors.forename: Paul
authors.initials: P
authors.lastname: Johnson
authors.affiliation: Department of Radiation Oncology, Loyola University Medical Center, Maywood, IL, USA.
authors.forename: Rakesh
authors.initials: R
authors.lastname: Patel
authors.affiliation: Department of Radiation Oncology, Loyola University Medical Center, Maywood, IL, USA.
authors.forename: Murat
authors.initials: M
authors.lastname: Surucu
authors.affiliation: Department of Radiation Oncology, Loyola University Medical Center, Maywood, IL, USA.
authors.forename: Mehee
authors.initials: M
authors.lastname: Choi
authors.affiliation: Department of Radiation Oncology, Loyola University Medical Center, Maywood, IL, USA.
authors.forename: Bahman
authors.initials: B
authors.lastname: Emami
authors.affiliation: Department of Radiation Oncology, Loyola University Medical Center, Maywood, IL, USA jroeske@lumc.edu.
authors.forename: John C
authors.initials: JC
authors.lastname: Roeske
mesh_terms: D000465:Algorithms; D016477:Artifacts; D054893:Cone-Beam Computed Tomography / Q000379:methods*; D006258:Head and Neck Neoplasms / Q000532:radiotherapy*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008670:Metals / Q000737:chemistry*; D019047:Phantoms, Imaging; D011856:Radiographic Image Enhancement / Q000379:methods; D061089:Radiotherapy, Image-Guided / Q000379:methods
chemical_list: D008670:Metals
keywords: CT; adaptive RT; artifact reduction; head and neck cancer; image-guided RT