Usefulness of dynamic magnetic resonance imaging in the diagnosis of orbital tumors

We studied four cases of orbital tumor by dynamic magnetic resonance imaging (MRI). The series comprised one case each of cavernous hemangioma, hemangiopericytoma, hemangioendothelioma and orbital schwannoma. Cavernous hemangioma showed gradual enhancement from the tumor margin, resulting in intense diffuse staining of the tumor mass in the late phase. Hemangiopericytoma showed rapid staining of the entire tumor. Hemangioendothelioma showed minimal staining of the tumor margin. Orbital schwannoma showed diffuse and rapid staining of the entire tumor. While postoperative recurrence was suspected in this case by standard MRI, dynamic MRI was suggestive of nonspecific scarring. Dynamic MRI was thus useful in the differential diagnosis of orbital tumors and in the evaluation of postoperative changes. (author)