Fig 1.
Enhanced axial images at portal venous phase of a 63-year female patient with portal hypertension secondary to liver cirrhosis with different percentage ASIRs, for objective evaluation of CT portal venography quality.
(A), (B), (C) and (D) were obtained with 0%, 30%, 50%, and 70% percentage ASIR reconstruction, respectively. The marked regions were ROIs in the main stem of portal vein, liver parenchyma, and subcutaneous fat.
Fig 2.
Subjective evaluation of rapid switching single source dual energy CT (ssDECT) portal venography images of a cirrhotic patient with portal hypertension secondary to liver cirrhosis with different percentage adaptive statistical iterative reconstructions (ASIRs).
(A), (B), (C) and (D) were obtained with 0%, 30%, 50%, and 70% percentage ASIRs reconstruction, respectively. The same slice thickness, field of view and nearly identical angle were used for reconstruction of all images.
Table 1.
Grading scale for qualitative analysis of portal vein.
Fig 3.
Objective image quality assessment of 70 keV monochromatic images with 0%, 30%, 50%, and 70% percentage ASIRs levels.
(A) Comparisons of image noise (IN with the unit of HU) of portal vein. (B) Comparisons of the contrast-to-noise-ratio (CNR) of portal vein to liver parenchyma.
Table 2.
Objective and subjective image quality assessment with different ASIR percentages.
Table 3.
Comparison of image quality assessment of different ASIR percentage groups.
Fig 4.
Subjective image quality assessment of the 70 keV monochromatic images with 0%, 30%, 50%, and 70% percentage ASIRs levels.
(A) Comparisons of the sharpness of portal vein boundaries. (B) Comparisons of the diagnostic ability (DA).