The supraorbital notch, infraorbital foramen, and lacrimal fossa are clinically palpable and function as important landmarks for performance of regional anesthesia (Fig. 48-1: Diagram of ocular anatomy).
The coat of the eye is composed of three layers: the sclera, uveal tract, and retina.
Whereas the fibrous outer layer of the sclera is protective, providing sufficient rigidity to maintain the shape of the eye, the anterior portion of the sclera, the cornea, is transparent, permitting light to enter the internal ocular structures.
The uveal tract consists of the iris, ciliary body, and choroid.
The pupil is part of the iris that controls the amount of light that enters by dilation (sympathetic innervation) or constriction (parasympathetic innervation).
The ciliary body produces aqueous humor.
The retina is a neurosensory membrane that converts light impulses to neural impulses that travel via the optic nerve to the brain.
Six intraocular muscles move the eye within the orbit.
The conjunctiva is a mucous membrane (topical administration of ophthalmic drugs) that covers the globe and serves as a lining of the eyelids.
Blood supply to the eye is from branches of the internal and external carotid arteries.