title: Electronic cleansing in fecal-tagging dual-energy CT colonography based on material decomposition and virtual colon tagging.
abstract: Dual-energy CT provides a promising solution to identify tagged fecal materials in electronic cleansing (EC) for fecal-tagging CT colonography (CTC). In this study, we developed a new EC method based on virtual colon tagging (VCT) for minimizing EC artifacts by use of the material decomposition ability in dual-energy CTC images. In our approach, a localized three-material decomposition model decomposes each voxel into a material mixture vector and the first partial derivatives of three base materials: luminal air, soft tissue, and iodine-tagged fecal material. A Poisson-based derivative smoothing algorithm smoothes the derivatives and implicitly smoothes the associated material mixture fields. VCT is a means for marking the entire colonic lumen by virtually elevating the CT value of luminal air as high as that of the tagged fecal materials to differentiate effectively soft-tissue structures from air-tagging mixtures. A dual-energy EC scheme based on VCT method, denoted as VCT-EC, was developed, in which the colonic lumen was first virtually tagged and then segmented by its high values in VCT images. The performance of the VCT-EC scheme was evaluated in a phantom study and a clinical study. Our results demonstrated that our VCT-EC scheme may provide a significant reduction of EC artifacts.
authors.forename: Wenli
authors.initials: W
authors.lastname: Cai
authors.forename: June-Goo
authors.initials: JG
authors.lastname: Lee
authors.forename: Da
authors.initials: D
authors.lastname: Zhang
authors.forename: Se Hyung
authors.initials: SH
authors.lastname: Kim
authors.forename: Michael
authors.initials: M
authors.lastname: Zalis
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Yoshida
mesh_terms: D000328:Adult; D016477:Artifacts; D003106:Colon / Q000000981:diagnostic imaging*; D023881:Colonography, Computed Tomographic / Q000379:methods*; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging*; D005243:Feces; D005260:Female; D006801:Humans; D008297:Male; D011856:Radiographic Image Enhancement / Q000379:methods; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D015900:Radiography, Dual-Energy Scanned Projection / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013194:Staining and Labeling / Q000379:methods; D013382:Subtraction Technique