Orbital cavernous hemangioma. A, CT scan (axial view) shows a well-circumscribed retrobulbar intraconal mass (asterisk). B, Low-magnification photomicrograph demonstrates large blood-filled spaces that are separated by relatively thin septa. C, Higher-magnification photomicrograph shows the large, irregular venous channels lined with flat endothelial cells and containing red blood cells. The collagenous capsule can be seen on the left side of the image.