Figure 5. Hepatocellular carcinoma(HCC) (Edmonson grade I) in a 67-year-old man. (a) Baseline ultrasound image shows a hypoechoic HCC nodule in the right lobe of the liver 2.3 cm in diameter. (b) Arterial phase image obtained at 23 s after contrast agent administration shows a homogeneous isoenhancement of the lesion. (c) Portal phase image obtained at 52 s. The nodule is isoechoic with respect to the surrounding liver. (d) Late portal phase image obtained at 280 s. The HCC is isoechoic with respect to the surrounding liver.