Equilibrium phase images of the liver using a contrast-enhancement boost instead of the portal vein phase

Figure 1 The patient selection flow chart. CT: Computed tomography; HBIR: Hybrid-type iterative reconstruction; RFA: Radiofrequency ablation; TACE: Transcatheter arterial chemoembolization.

Figure 2 An example of a clinical image used in the evaluation. A 77-year-old woman with a diagnosis of hepatocellular carcinoma (arrows) based on a pathological diagnosis. The qualitative evaluation results showed that the vessel visualization of the portal vein provided by the contrast enhancement boost of equilibrium phase [CE-boost (EP)] images and that provided by the portal vein phase (PVP) images was comparable. CE-boost (EP) was significantly superior in lesion conspicuity. In this patient’s case, the vessel visualization of the portal vein was rated with an average of 4.00 points on PVP and 4.00 points on CE-boost (EP). The lesion conspicuity was rated with an average of 3.50 points on PVP and 4.00 points on CE-boost (EP). A and B: Portal vein phase images; C and D: Equilibrium phase images; E and F: Contrast enhancement boost of equilibrium phase images.

Figure 3 Examples of clinical images of two patients used in the evaluation. A: Images of a 51-year-old woman, equilibrium phase (EP) image; B: Images of a 51-year-old woman, contrast enhancement boost (CE-boost) of EP image (the image noise was reduced by smoothing during the CE-boost process); C: Images of a 78-year-old-man, EP image; D: Images of a 78-year-old-man, CE-boost of EP image, however, after the CE-boost processing, the high-signal noise seen in the EP is emphasized and more prominent in image.