title: Statistical iterative reconstruction for streak artefact reduction when using multidetector CT to image the dento-alveolar structures.
abstract: OBJECTIVE
  When metallic prosthetic appliances and dental fillings exist in the oral cavity, the appearance of metal-induced streak artefacts is not avoidable in CT images. The aim of this study was to develop a method for artefact reduction using the statistical reconstruction on multidetector row CT images.
  
  
  METHODS
  Adjacent CT images often depict similar anatomical structures. Therefore, reconstructed images with weak artefacts were attempted using projection data of an artefact-free image in a neighbouring thin slice. Images with moderate and strong artefacts were continuously processed in sequence by successive iterative restoration where the projection data was generated from the adjacent reconstructed slice. First, the basic maximum likelihood-expectation maximization algorithm was applied. Next, the ordered subset-expectation maximization algorithm was examined. Alternatively, a small region of interest setting was designated. Finally, the general purpose graphic processing unit machine was applied in both situations.
  
  
  RESULTS
  The algorithms reduced the metal-induced streak artefacts on multidetector row CT images when the sequential processing method was applied. The ordered subset-expectation maximization and small region of interest reduced the processing duration without apparent detriments. A general-purpose graphic processing unit realized the high performance.
  
  
  CONCLUSIONS
  A statistical reconstruction method was applied for the streak artefact reduction. The alternative algorithms applied were effective. Both software and hardware tools, such as ordered subset-expectation maximization, small region of interest and general-purpose graphic processing unit achieved fast artefact correction.
authors.affiliation: 1 Department of Computer Science, Faculty of Engineering, Kitami Institute of Technology, Kitami, Japan.
authors.forename: J
authors.initials: J
authors.lastname: Dong
authors.forename: Y
authors.initials: Y
authors.lastname: Hayakawa
authors.forename: C
authors.initials: C
authors.lastname: Kober
mesh_terms: D000328:Adult; D000465:Algorithms; D000539:Alveolar Process / Q000000981:diagnostic imaging*; D016477:Artifacts; D003196:Computer Graphics / Q000706:statistics & numerical data; D003722:Dental Alloys / Q000737:chemistry; D003723:Dental Amalgam / Q000737:chemistry; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000706:statistics & numerical data*; D016013:Likelihood Functions; D061330:Multidetector Computed Tomography / Q000706:statistics & numerical data*; D012984:Software / Q000706:statistics & numerical data; D014070:Tooth / Q000000981:diagnostic imaging*
chemical_list: D003722:Dental Alloys; D003723:Dental Amalgam
keywords: CT; X-ray; dento-alveolar region; statistical iterative reconstruction; streak artefact reduction
references.citation: Dentomaxillofac Radiol. 2011 Mar;40(3):184-90
references.pmid: 21346086
references.citation: Int J Comput Assist Radiol Surg. 2011 Sep;6(5):635-40
references.pmid: 21207177
references.citation: Comput Methods Programs Biomed. 2010 Jun;98(3):261-70
references.pmid: 19850372
references.citation: Med Phys. 2006 Aug;33(8):2852-9
references.pmid: 16964861
references.citation: Phys Med Biol. 2009 Nov 7;54(21):6575-91
references.pmid: 19826202
references.citation: Eur J Nucl Med Mol Imaging. 2003 Nov;30(11):1510-9
references.pmid: 14579091
references.citation: J Comput Assist Tomogr. 2008 Jul-Aug;32(4):630-3
references.pmid: 18664853
references.citation: Med Phys. 2010 Dec;37(12):6166-77
references.pmid: 21302773
references.citation: Phys Med Biol. 2012 Apr 7;57(7):2039-61
references.pmid: 22430037
references.citation: AJR Am J Roentgenol. 2010 Jan;194(1):191-9
references.pmid: 20028923
references.citation: Ann Nucl Med. 2009 Jul;23(5):443-9
references.pmid: 19399580
references.citation: Phys Med Biol. 2006 Jan 21;51(2):237-52
references.pmid: 16394336
references.citation: Inverse Probl. 2009 Jan 1;25(12):1230009
references.pmid: 20376330
references.citation: Med Phys. 2010 Feb;37(2):620-8
references.pmid: 20229871
references.citation: J Nucl Med. 2008 Jul;49(7):1047-52
references.pmid: 18552154
references.citation: Dentomaxillofac Radiol. 2013;42(4):20120105
references.pmid: 23420861
references.citation: Br J Radiol. 2013 Jan;86(1021):20120161
references.pmid: 23255538
references.citation: J Comput Assist Tomogr. 2008 Jul-Aug;32(4):621-9
references.pmid: 18664852
references.citation: Radiology. 2011 Jun;259(3):894-902
references.pmid: 21357521
references.citation: Eur Radiol. 2011 Mar;21(3):510-7
references.pmid: 21249371
references.citation: Oral Surg Oral Med Oral Pathol Oral Radiol. 2013 Feb;115(2):e63-73
references.pmid: 23036800