Fig. 20. The arterial supply of the eyelids and midface. A. The upper eyelid contains two arcades, whereas the lower typically has one main arcade with or without a more rudimentary secondary arcade. Note that the palpebral arteries pierce the orbital septum to communicate with the anterior orbit. B. Major anastomoses of the internal (green) and external (red) carotid arterial supplies include the transverse facial and dorsal nasal arteries; the zygomatic/superficial temporal and lacrimal/lateral palpebral arteries; and the frontal branch of the superficial temporal and supraorbital arteries. Note that the infraorbital artery is a branch of the external carotid artery, arising from the internal maxillary artery within the pterygopalatine fossa. (A from Dutton JJ: Atlas of Clinical and Surgical Orbital Anatomy, p 79. Philadelphia, WB Saunders, 1994)