The Optic
Nerve and
associated Diseases
The second cranial nerve. Largest sensory nerve of the eye; carries impulses for sight from the retina to the brain. Composed of retinal nerve fibers that exit the eyeball through the optic disk and exit the orbit through the optic foramen.
The Fovia
Centrales and
associated Diseases
The Fovia Centrales is a central pit in the macula that produces sharpest vision. Contains a high concentration of cones and no retinal blood vessals.
The Retina
and
associated Diseases
The retina is part eye (embryologically part of the brain) that converts images from the eye's optical system into electrical impulses that are sent along the optic nerve for transmission to the brain. Forms a thin membranous lining of the rear two thirds of the globe. Consists of layers that include Rods(where vision) and cones(color and what vision); bipoler, amacrine, gaglion, horizontal and muller cells, and all interconnecting nerve fibers.
The Choroid
and
associated Diseases
The Choroid is a vasculer (major blood vessel) layer of the eye lying between the retina and the sclera. Provides nourishment to the outer layers of the retina. Forms part of the uvea, along with the ciliary body and iris.
The Sclera
and
associated Diseases
The sclera is an opaque, fibrous, protective outer layer of the eye ("white of the eye") that is directly continuous with the cornea in front and with the sheath that covers the optic nerve behind. Contains collagen and elastic fibers.
The Optic
Diskand
associated Diseases
The optic disk is the ocular end of the optic nerve that denotes the exit of retinal nerve fibers the eye and entrance of blood vessels to the eye. AKA blind spot.
The Macula
and
associated Diseases
The macula is a small central area of the retina surrounding the fovia centrales; area of acute central vision. Is responsible for the "what" vision.
The Ora
Serrata and
associated Diseases
The ora serrata is the front edge of the retina, located about 6.5 mm behind the corneo-scleral junction (limbus). Has a tooth-like appearance.
The Canal
of Schlemm and
associated Diseases
The canal of Schlemm is a circular channel deep in the corneal-scleral junction (limbus); conducts aqueous from the anterior chamber in the eye through aqueous veins into the bloodstream.
The Conjutiva
and
associated Diseases
The conjunctiva is transparent mucus membrane covering the outer surface of the eyeball except the cornea, and lining the inner surface of the eyelids. The Bulbar portion covers the external eyeball and the palberal portions lines the inner side of eyelids.
The Iris
and
associated Diseases
The iris is a pigmented tissue lying behind the cornea that gives color to the eye and controls the amount of light entering the eye by varying the size of pupillary opening. Most forward extension of the middle (uveil) layer of the eye; separates the interior chamber from the posterior chamber.
The Lens
and
associated Diseases
The lens is the natural crytaline lens of the eye. Transparent, biconvex interocular tissue that helps bring rays of light to focus on the retina. suspended by fine ligaments (zonules) attached between the ciliary processes. It's major function is accomodation for near distance viewing.
The Pupil
and
associated Diseases
The pupil is a variable-sized black circular opening in the center of the iris that regulates the amount of light that enters the eye.
The Cornea
and
associated Diseases
The cornea is the transparent front part of the eye that covers the iris, pupil and anterior chamber and provides most of the eye's optical power. It has five layers: The epithelium, Bowman's membrane, the stroma, Decemet's membrane, and the endotheium.
The Aqueous
Humorand
associated Diseases
The Aqueous humor is a clear, watery fluid that fills the space between the back surface of the cornea and the front surface of the vitreous, bathing the lens. It is produced by the ciliary processes and nourishes the cornea, iris, and lens and maintains inner ocular pressure.
TheVitreous
Humor and
associated Diseases
The vitreous is a transparent, colorless gelatinous mass (fine collagen fibrals hyaluronic acid) that fills the rear two thirds of the eyeball, between the lens and the retina.
The Suspensory
Ligaments and
associated Diseases
The suspensory ligaments (zonules of Zinn) are radially arranged fibers that suspend the lens from the ciliary body and hold it in position.
The Ciliary
Body and
associated Diseases
The ciliary body is the circumferential tissue inside the eye composed of the ciliary muscle (involved in lens accomodation and control of inneroculer pressure) and seventy ciliary processes that produce aqueous.