MRI OF SUBPERIOSTEAL HEMATOMA OF THE ORBIT

Objective: The MR findings of two cases of subperiosteal hematoma of t he orbit are described. Materials and Methods: We present two cases of subperiosteal hematoma of the orbit following minor head trauma, the first presenting with chronic progressive exophthalmos and the second with acute proptosis. Results: Both cases showed a well-defined biconv ex mass with a curvilinear hypointense band in the superior portion of the orbit. In Case 1 chronic hematoma demonstrated high signal on bot h T1- and T2-weighted imaging, and in Case 2 acute hematoma displayed intermediate signal on T1-weighted imaging and high signal on T2-weigh ted imaging. Follow-up MRI in Case 2 demonstrated the typical signal c hanges from acute to subacute hematoma. Conclusion: Subperiosteal hema toma has a characteristic appearance on MRI which is virtually diagnos tic. In proper clinical settings MRI is the modality of choice for the detection and characterization of this hematoma.