According to Dartmouth's online textbook, "Basic Human Anatomy," the superior orbital fissure is a cleft in the bones of the skull located within the hollows (or orbits) of the eye. Several important nerves pass through this cleft. It is larger and higher than the inferior orbital fissure.
The inferior orbital fissure is located near the outside corner of the eye socket or orbit. The superior orbital fissure is centrally located, curving toward the upper-right corner of the eye orbit. There is one superior orbital fissure in each eye. These fissures are clefts in the sphenoid bone. According to FreeDictionary.com, the sphenoid bone is a butterfly-shaped plate of bone that makes up the bridge of the nose and the back section of the eye sockets.