title: Reduction of peristalsis-related gastrointestinal streak artifacts with dual-energy CT: a patient and phantom study.
abstract: The purpose of the study was to assess the ability of rapid-kV switching (rs) dual-energy computed tomography (DECT) to reduce peristalsis-related streak artifact.
  
  
  
  rsDECT images of 100 consecutive patients (48 male, 52 female, mean age 57 years) were retrospectively evaluated in this institutional review board-approved study. Image reconstructions included virtual monochromatic 70 and 120 keV images, as well as iodine(-water) and water(-iodine) material decomposition images. We recorded the presence and severity of artifacts qualitatively (4-point scale) and quantitatively [iodine/water concentrations, Hounsfield units, gray scale values (GY)] and compared to corresponding unaffected reference tissue. Similar measures were obtained in DECT images of a peristalsis phantom. Wilcoxon signed-rank and paired t tests were used to compare results between different image reconstructions.
  
  
  
  Peristalsis-related streak artifacts were found in 49 (49%) of the DECT examinations. Artifacts were significantly more severe in 70, 120, and water(-iodine) images than in iodine(-water) images (qualitative readout P < 0.001, each). Quantitative measurements were significantly different between the artifact and the reference tissue in 70, 120 keV, and water(-iodine) images (P < 0.001 for both HU and GY for each image reconstruction), but not significantly different in iodine(-water) images (iodine concentrations P = 0.088 and GY P = 0.111). Similar results were seen in the peristalsis DECT phantom study.
  
  
  
  Peristalsis-related streak artifacts seen in 70, 120 keV, and water(-iodine) images are substantially reduced in iodine(-water) images at rsDECT.
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, 505 Parnassus Ave, M-372, Box 0628, San Francisco, CA, 94143-0628, USA.|Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Raemistrasse 100, 8032, Zurich, Switzerland.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Winklhofer
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, 505 Parnassus Ave, M-372, Box 0628, San Francisco, CA, 94143-0628, USA.
authors.forename: Jack W
authors.initials: JW
authors.lastname: Lambert
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, 505 Parnassus Ave, M-372, Box 0628, San Francisco, CA, 94143-0628, USA.
authors.forename: Zhen Jane
authors.initials: ZJ
authors.lastname: Wang
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, 505 Parnassus Ave, M-372, Box 0628, San Francisco, CA, 94143-0628, USA.
authors.forename: Yuxin
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, 505 Parnassus Ave, M-372, Box 0628, San Francisco, CA, 94143-0628, USA.
authors.forename: Robert G
authors.initials: RG
authors.lastname: Gould
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, 505 Parnassus Ave, M-372, Box 0628, San Francisco, CA, 94143-0628, USA.
authors.forename: Ronald J
authors.initials: RJ
authors.lastname: Zagoria
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, 505 Parnassus Ave, M-372, Box 0628, San Francisco, CA, 94143-0628, USA. Ben.Yeh@ucsf.edu.
authors.forename: Benjamin M
authors.initials: BM
authors.lastname: Yeh
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016477:Artifacts; D005260:Female; D041981:Gastrointestinal Tract / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010528:Peristalsis; D019047:Phantoms, Imaging; D015900:Radiography, Dual-Energy Scanned Projection / Q000379:methods; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult
keywords: Artifact reduction; Bowel peristalsis; Dual-energy computed tomography; Image quality; Iodine image