THE INTERNAL CAROTID ARTERY 



569 



The Lacrimal Artery (a. lacrimalis) arises close to the optic foramen, and is one 

 of the largest branches derived from the ophthalmic: not infrequently it is given 

 off before the artery enters the orbit. It accompanies the lacrimal nerve along 

 the upper border of the Rectus lateralis, and supplies the lacrimal gland. Its 

 terminal branches, escaping from the gland, are distributed to the eyelids and con- 

 junctiva : of those supplying the eyelids, two are of considerable size and are named 

 the lateral palpebral arteries; they run mediaiward in the upper and lower lids 

 respectively and anastomose with the medial palpebral arteries, forming an arterial 

 circle in this situation. The lacrimal artery give off one or two zygomatic branches, 

 one of which passes through the zygomatico-temporal foramen, to reach the tem- 

 poral fossa, and anastomoses with the deep temporal arteries; another appears 

 on the cheek through the zygomatico-facial foramen, and anastomoses with the 

 transverse facial. A recurrent branch passes backward through the lateral part of 

 the superior orbital fissure to the dura mater, and anastomoses with a branch of 

 the middle meningeal artery. The lacrimal artery is sometimes derived from one 

 of the anterior branches of the middle meningeal artery. 



Dorsal nasal Medial palpebral 



r f\\Frontal 



Anterior ethmoidal 



Posterior ethmoidal 



) Zygomatic branches 



of lacrimal 



Miiscular 



Lacrimal 



Ophthalmic 



Internal carotid 



FIG. 514. The ophthalmic artery and its branches. 



The Supraorbital Artery (a. supraorbitalis') springs from the ophthalmic as that 

 vessel is crossing over the optic nerve. It passes upward on the medial borders 

 of the Rectus superior and Levator palpebrse, and meeting the supraorbital nerve 

 accompanies it between the periosteum and Levator palpebrse to the supraorbital 

 foramen; passing through this it divides into a superficial and a deep branch, 

 which supply the integument, the muscles, and the pericranium of the forehead, 

 anastomosing with the frontal, the frontal branch of the superficial temporal, and 

 the artery of the opposite side. This artery in the orbit supplies the Rectus superior 

 and the Levator palpebrse, and sends a branch across the pulley of the Obliquus 

 superior, to supply the parts at the medial palpebral commissure. At the supra- 

 orbital foramen it frequently transmits a branch to the diploe. 



