Hemangioma of long tubular bone: imaging characteristics with emphasis on magnetic resonance imaging.

OBJECTIVE To investigate the imaging findings, especially the MRI findings, of intraosseous hemangioma of long tubular bones and to improve the recognition of this rare tumor. MATERIALS AND METHODS The imaging characteristics of 16 histopathologically diagnosed long tubular bone hemangioma lesions were retrospectively reviewed on radiography (n = 16), CT (n = 16), and MRI (n = 15). RESULTS Thirteen of 16 lesions were intramedullary, whereas the other three were cortical, subperiosteal, and mixed intracortical and intramedullary, respectively. The radiologic appearance of long bone intraosseous hemangioma was divided into five types: cyst-like (n = 7), mesh- or honeycomb-like (n = 6), medullary sclerosis (n = 1), cortical thickening (n = 1), and cortical lytic type (n = 1). Radiography and CT allowed the identification of sclerotic margins in eight cases, thickened trabeculae in six cases, internal calcification in one case, cortical thickening in one case, and fracture in four cases. Two lesions were confusing on radiography but clearly identifiable on MRI. All intraosseous hemangioma showed high signal intensity on T2-weighted imaging and intermediate signal intensity on T1-weighted imaging. Four cyst-like lesions showed peripheral and filling enhancement, whereas others exhibited diffuse enhancement with an intensity similar to adjacent vessels. CONCLUSION Cystic and mesh types are the most common types of hemangioma in long tubular bones. MRI can help to define the location and extent of lesions. The tumor usually shows high signal intensity on T2-weighted imaging and intermediate signal intensity on T1-weighted imaging. Peripheral and filling or diffuse enhancement with an intensity similar to vessels is helpful for the diagnosis of intraosseous hemangioma.