Fig. 14. Orbital venous flow malformation. Axial computed tomography scan showing an ill-defined, dense, inhomogeneous orbital lesion with the patient in a supine position (A). Note the phlebolith, which indicates venous stagnation. As the venous flow malformation distends with the patient in the prone position, the lesion enlarges (B). (Courtesy of Dr. John V. Linberg, University of West Virginia, Morgantown, WV)