Hemangioma is a common benign vascular neoplasm that closely resembles normal vessels and can be found in all organs of the human body. Vascular lesions can be classified as infantile hemangiomas or vascular malformations on the basis of their natural history, location, cellular turnover, and histologic characteristics. The magnetic resonance (MR) imaging features of vascular malformations of the central nervous system depend on the pathologic subtype. Soft-tissue vascular malformations can be categorized with combined MR imaging and MR angiography as either high- or low-flow. Osseous vascular malformations commonly demonstrate a high-signal-intensity trabecular pattern at both T1- and T2-weighted MR imaging. A group of more aggressive vascular neoplasms, including hemangioendothelioma, hemangiopericytoma, and glomus tumor, have a nonspecific appearance at MR imaging. In the liver and spleen, hemangiomas are typically hyperintense at T2-weighted MR imaging, with a centripetal filling pattern after administration of gadopentetate dimeglumine. Vascular lesions can involve several organs or systems in angiomatous syndromes. MR imaging allows characterization of a hemangioma with typical features, which vary depending on anatomic location. Familiarity with these features facilitates diagnosis and management of these anomalies.
Copyright RSNA, 2004