Fig. 4

Contrast-enhanced triphasic CT imaging of typical and atypical HCC cases: A case of typical radiological appearance of multiple HCC (LR-5) (a–d). a Cirrhotic liver changes, b with right hepatic lobe focal lesion seen at segment VI displaying intense arterial enhancement, c with washout of contrast in portovenous phase, d being hypo dense to hepatic parenchyma in delayed equilibrium study. e–h Another focal lesion is seen at segment VII with similar enhancement pattern. A case of infiltrative HCC (LR-5) (i–l). i Cirrhotic liver changes, j with malignant infiltration of the left hepatic lobe that shows heterogeneous enhancement in the arterial phase with low density areas indicative of necrosis k and displays wash out of contrast at portovenous phase, l being hypodense to hepatic parenchyma in delayed equilibrium study. A case of multiple hypovascular HCC (LR-5) (m–p). m Cirrhotic liver changes, n–p with multiple bilobar variable sized hepatic focal lesions showing no contrast uptake in different study phases, the largest at left hepatic lobe segment II measuring 5 × 4.8 cm. A case of HCC on top of non-cirrhotic liver (LR-M) (q–t). q Non cirrhotic liver, r with right hepatic lobe segment VI large exophytic well defined focal mass lesion displaying thick irregular peripheral arterial enhancement and central hypo dense area of necrosis, s with washout of contrast at portovenous phase, t and delayed phases