The medial palpebral arteries (internal palpebral arteries) are arteries of the head. They are two in number, superior and inferior, arise from the ophthalmic

Ophthalmic artery

The ophthalmic artery is the first branch of the internal carotid artery distal to the cavernous sinus. Branches of the OA supply all the structures in the orbit as well as some structures in the nose, face and meninges...

, opposite the pulley of the Obliquus superior.

Course

They leave the orbit to encircle the eyelids near their free margins, forming a superior and an inferior arch, which lie between the Orbicularis oculi and the tarsi.

The superior palpebral arch anastomoses, at the lateral angle of the orbit, with the zygomaticoörbital branch of the temporal artery and with the upper of the two lateral palpebral branches from the lacrimal artery

Lacrimal artery

The lacrimal artery arises close to the optic foramen, and is one of the largest branches derived from the ophthalmic artery: not infrequently it is given off before the artery enters the orbit....

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The inferior palpebral arch anastomoses, at the lateral angle of the orbit, with the lower of the two lateral palpebral branches from the lacrimal and with the transverse facial artery

Transverse facial artery

The transverse facial artery is an artery that branches from the superficial temporal artery and runs across the face.-Course:The transverse facial artery is given off from the superficial temporal artery before that vessel leaves the parotid gland; running forward through the substance of the...

, and, at the medial part of the lid, with a branch from the angular artery

Angular artery

The angular artery is the terminal part of the facial artery; it ascends to the medial angle of the eye's orbit, imbedded in the fibers of the angular head of the Quadratus labii superioris, and accompanied by the angular vein....

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From this last anastomoses a branch passes to the nasolacrimal duct

Nasolacrimal duct

The nasolacrimal duct carries tears from the lacrimal sac into the nasal cavity. Excess tears flow through nasolacrimal duct which drains into the inferior nasal meatus...

, ramifying in its mucous membrane

Mucous membrane

The mucous membranes are linings of mostly endodermal origin, covered in epithelium, which are involved in absorption and secretion. They line cavities that are exposed to the external environment and internal organs...

, as far as the inferior meatus

Inferior meatus

The inferior meatus, the largest of the three meatuses of the nose, is the space between the inferior concha and the floor of the nasal cavity....

 of the nasal cavity

Nasal cavity

The nasal cavity is a large air filled space above and behind the nose in the middle of the face.- Function :The nasal cavity conditions the air to be received by the other areas of the respiratory tract...

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