Figure 5b. (a) Dynamic CT scan obtained immediately after contrast material injection demonstrates a large mass with peripheral enhancement in the inferior right hepatic lobe. The central two-thirds of the mass is relatively hypoattenuating. The mass causes mass effect on the adjacent right kidney. A thin rim of normal liver is seen anteriorly and demonstrates less enhancement than the mass. (b) Delayed CT scan obtained 8 minutes after contrast material injection shows the mass with some washout of the peripheral enhancement and an attenuation that is closer to that of normal liver. The mass demonstrates persistent hypoattenuation centrally.