fig6

Figure 6. Threshold Growth. Axial CT images of a 21 mm mass in the right hepatic lobe. The mass demonstrates arterial phase hyperenhancement during the arterial phase (white arrow, A), and “washout” with “capsule” (black arrow) on the portal venous (B) and delayed phases (C). Axial CT performed 5 months prior demonstrates a 12 mm mass on the portal venous phase (D, black arrowhead). The interval growth is more than 50% in less than 6 months, therefore, the mass also demonstrates threshold growth. The most appropriate category for this mass is LI-RADS 5. CT: computed tomography; LI-RADS: Liver Imaging Reporting and Data System