[Arterial blood supply and innervation of the rectus muscles of the eyeball].

UNLABELLED: The authors report on the arterial blood supply and the innervation of the rectus muscles of the eyeball from human orbital dissections. MATERIAL AND METHODS: Hundred human orbits were dissected using a superior approach after arterial injection with colored latex. The different arterial pedicles for each muscle were noted and the nervous supply was studied. RESULTS: The arterial blood supply of the rectus muscles comes from different branches of the ophthalmic artery, usually the inferior muscular artery, the lacrimal artery, the superior muscular artery when it exists, and by small branches arising from the ophthalmic artery. The superior rectus is supplied by branches of the ophthalmic artery and the lacrimal artery (1 to 5 pedicles). The medial rectus is supplied by branches of the ophthalmic artery and the inferior muscular artery (5 to 9 branches). The inferior muscle rectus is principally supplied by the inferior muscular artery (4 pedicles) and the lateral muscle is supplied by the lacrimal artery or the lateral muscular artery (3 to 6 branches). For innervation, the abducens nerve supplies the lateral rectus; the other muscles are supplied by the oculomotor nerve whose superior branch supplies the superior rectus and whose inferior branch, supplies the inferior and medial rectus. DISCUSSION: The arterial blood supply is variable. The arteries which lie near the rectus muscles usually supply one or more branches to the muscles. The arteries go into the muscles through their conal side. This arterial supply is at the posterior part of the muscle. Innervation, in contrast, is very constant and fixed. CONCLUSION: The arterial blood supply to the rectus muscles is variable but always substantial. The pedicles are numerous, often 3 to 5 for each muscle. Innervation is fixed and constant.