Ferumoxide-enhanced MRI of sideronecrosis superimposed on genetic hemochromatosis.

Genetic hemochromatosis is an autosomal recessive disorder characterized by excessive iron absorption from the gut, resulting in increased total body iron stores, multisystem organ dysfunction, and an increased risk of hepatocellular carcinoma. The magnetic susceptibility effects of excess hepatocellular iron generally cause diffuse hepatic signal loss on T2- or T2*-weighted MR images. Although hepatic iron deposition is usually diffuse, focal areas of iron sparing can occur, and, when present, superimposed neoplasm is a consideration. We describe a patient with cirrhosis, hemochromatosis, and multiple small benign relatively hyperintense iron-poor foci consisting of piecemeal sideronecrosis.