title: Metal artifact reduction and image quality evaluation of lumbar spine CT images using metal sinogram segmentation.
abstract: Metal artifacts often appear in the images of computed tomography (CT) imaging. In the case of lumbar spine CT images, artifacts disturb the images of critical organs. These artifacts can affect the diagnosis, treatment, and follow up care of the patient. One approach to metal artifact reduction is the sinogram completion method. A mixed-variable thresholding (MixVT) technique to identify the suitable metal sinogram is proposed. This technique consists of four steps: 1) identify the metal objects in the image by using k-mean clustering with the soft cluster assignment, 2) transform the image by separating it into two sinograms, one of which is the sinogram of the metal object, with the surrounding tissue shown in the second sinogram. The boundary of the metal sinogram is then found by the MixVT technique, 3) estimate the new value of the missing data in the metal sinogram by linear interpolation from the surrounding tissue sinogram, 4) reconstruct a modified sinogram by using filtered back-projection and complete the image by adding back the image of the metal object into the reconstructed image to form the complete image. The quantitative and clinical image quality evaluation of our proposed technique demonstrated a significant improvement in image clarity and detail, which enhances the effectiveness of diagnosis and treatment.
authors.affiliation: Biological Engineering Program, Faculty of Engineering, King Mongkut's University of Technology Thonburi, Bangkok, Thailand.
authors.forename: Titipong
authors.initials: T
authors.lastname: Kaewlek
authors.affiliation: Department of Control Systems and Instrumentation Engineering, Faculty of Engineering, King Mongkut's University of Technology Thonburi, Bangkok, Thailand.
authors.forename: Diew
authors.initials: D
authors.lastname: Koolpiruck
authors.affiliation: X-ray CT and Medical Imaging Laboratory, Biomedical Electrnics and Systems Development Unit, National Electronics and Computer Technology Center, Pathumthani, Thailand.
authors.forename: Saowapak
authors.initials: S
authors.lastname: Thongvigitmanee
authors.affiliation: Faculty of Radiological Technology, Rangsit University, Pathumthani, Thailand.
authors.forename: Manus
authors.initials: M
authors.lastname: Mongkolsuk
authors.affiliation: Division of Diagnostic Radiology, Department of Radiology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand.
authors.forename: Sastrawut
authors.initials: S
authors.lastname: Thammakittiphan
authors.affiliation: Division of Diagnostic Radiology, Department of Radiology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand.
authors.forename: Siri-on
authors.initials: SO
authors.lastname: Tritrakarn
authors.affiliation: Division of Diagnostic Radiology, Department of Radiology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand.
authors.forename: Pipat
authors.initials: P
authors.lastname: Chiewvit
mesh_terms: D000465:Algorithms; D016477:Artifacts; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging* / Q000601:surgery; D008670:Metals; D065289:Pedicle Screws; D019047:Phantoms, Imaging; D011856:Radiographic Image Enhancement / Q000379:methods*; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D014057:Tomography, X-Ray Computed / Q000295:instrumentation / Q000379:methods*
chemical_list: D008670:Metals
keywords: Metal artifacts reduction; image quality evaluation; lumbar spine image; metal sinogram; segmentation