Eye With Orbit

The human eye with orbit refers to the eyeball and its supporting structures housed within the bony cavity of the skull called the orbit.

Orbit: Bony Eye Socket

The orbit is a pyramidal cavity formed by seven bones: maxilla, zygomatic bone, frontal bone, ethmoid bone, lacrimal bone, sphenoid bone, and palatine bone.

It hosts the eyeball along with extraocular muscles, fat, nerves, blood vessels, and the lacrimal (tear) gland.

The orbit provides structural support and protection to the eye and creates pathways for critical nerves and blood vessels through openings like the optic canal and superior orbital fissure.

Eye Structure Within the Orbit

The eyeball itself is a spherical structure with three main layers: the outer fibrous layer (sclera and cornea), the middle vascular layer (choroid, ciliary body, iris), and the inner neural layer (retina).

The optic nerve exits the back of the eye through the orbit, relaying visual information to the brain.

Extraocular muscles attached to the eye and orbit walls control voluntary eye movement.

Key Functions

The orbit's structure shields the eye from trauma, helps maintain its position, and houses tissues vital for eye mobility and function.

Multiple foramina and fissures in the orbit allow passage for nerves such as the optic nerve (CN II), oculomotor (CN III), trochlear (CN IV), abducens (CN VI), and the ophthalmic branch of the trigeminal nerve (CN V).