RADIOLOGY: HEPATOBILIARY: Case# 32898: HEMANGIOMA. 51 year old male with right upper quadrant pain. There is a large low attenuation lesion within the left lobe of the liver. With contrast administration, the lesion displays a nodular enhancing rim. On delayed scans, the lesion appears isodense to intrahepatic blood vessels. Hemangiomas are a common incidental finding on routine imaging surveys of the liver and may pose an important diagnostic problem in patients with a known primary malignancy. Hemangiomas are the most common benign tumors of the liver. They are usually found in the right hepatic lobe and are subcapsular in location. The CT appearance of hemangiomas after a bolus injection of iodinated contrast material with dynamic scanning demonstrates a dense peripheral enhancement, which eccentrically fills in toward the center of the lesion on delayed scan. This is the most common finding and is seen in approximately 85% of lesions greater than 3cm in size. The angiographic appearance of a hemangioma is classic, with puddling of contrast material within the tumor, which remains visible on delayed, prolonged filming sequences. Some hemangiomas exhibit atypical features such as cystic areas probably caused by hemorrhage or thrombosis. Other lesions simply fail to show the typical pattern well enough to confirm the diagnosis.