A literature review of the vascular system in the human orbit

Some clinical ophthalmological problems led us to a study of literature data about the blood vessels in the human orbit. This inquiry confronted us with a profound knowledge of individual vessels. Remarkably, the arterial system appears to be in general more variable than the venous system. Radiologists have also noticed the difference in variability between the two vascular systems. Mainly for this reason, they consider topographical information obtained from phlebograms more useful than that obtained from arteriograms. However, the spatial arrangement of the orbital vessels has been given little consideration in literature. The same can be said of the relationship of the vessels with their immediate surroundings, connective tissue. Of the arterial system, only the ophthalmic artery and the posterior ciliary arteries have been described in this way, and only in relation to the optic sheath. Of the venous system, few authors mention the relation of parts of it with elastic tissue and the tight connective tissue of the superior orbital fissure. Only one author observed a complete septal structure in which the superior ophthalmic vein is suspended. The reports on the connective tissue relationships thus appear to be fairly fragmentary. Finally, the architecture of orbital microvascularization has also hardly been dealt with. A field for further anatomical study thus seemed to invite exploration.