Eye Anatomy

    The eye is composed of several parts: cornea, iris, pupil, lens, corpus vitreum, retina, macula, uvea, optic nerve. Eye anatomy is displayed below.

    Learning eye anatomy is fundamental to truly understand how the eye works. Eye structure is complex and has a fragile balance. The eye is composed of several structures that work together to fulfill an important function: transforming rays of light that come from the outside into signals that have to be transmitted to the central nervous system in order to make us see The most complex phase of this process happen in the retina.

    Eye diseases happen when even a single part is damaged, being it the cornea, iris, pupil, lens, corpus vitreum, retina, macula, uvea, optic nerve.

     

    Move your cursor over the colored words to read the corresponding description

    Cornea

    Cornea is a transparent anatomic structure, non vascularized, rich in nerve endings and is the main optic component in the ocular system. It has five layers; the outer one, called epithelium, is composed of five or six layers of cells of different thickness.

    Pupil

    Pupil is a hole through which light enters the eye. Light coming from the pupil, through the lens reaches the retina. Its size is important for eye surgery.

    Lens

    The lens is made of a small biconvex lens, with a thickness of about 3,6mm. Its function is to correct focal vergence when we focus on objects that are placed at different distances from the eye.

    Iris

    The iris is a pigmented membrane, located behind the cornea and before the lens, it has a central hole (pupil). Its function is to manage light quantity that gets inside the eye.

    Vitreous Humor

    Vitreous humor is located between the retina and the lens; it is composed of a transparent gelatinous substance and its function consists in keep the retina adherent to the pigmented epithelium.

    Optic Nerve

    Optic nerve links the eye to the brain, just like a cable connects a videocamera to the television. It is made of about two millions nervous fibers that can become less and less because of the time passing or diseases.

    Macula

    Macula is the most central portion of the retina and controls our ability to recognize objects and colors, to read or write, etc, It contains a very small area called central fovea: this is a highly specialized structure that is responsible, in case of very strong brightness, for the best possible visual acuity, color perception and contrast sensitivity. Inside the macula, 3 kinds of cones can be found and everyone is sensitive for a special wavelenght: red, green and blue. The colored images we see, come from the combination of stimula coming from the different cones. Cones are mostly located in the central fovea and in the adjacent retinal portion, where they are placed one next to the other.

    Fovea

    Fovea is the central part of the macula, the most sensitive part of the retina. Is has no vessels but a high concentration of photoreceptors, especially cones.

    Retina

    Retina is a sensitive membrane, split in three portions: a pigmented layer, a vascular layer, a layer composed of nervous fibers and photoreceptors (6 millions cones and 120 retinal rods). When the focused image falls onto the retina, a series of physical, chemical and electric events happen and, through the optic nerve, the information gets to the visual cortex, where it is corrected and elaborated.

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    Vitreous

    Vitreous

    Humor vitreous is located between the retina and the lens, and it is composed of a jelly transparent substance. Its function is to keep the retina adherent to the pigmented epithelium.

    Optic Nerve

    Optic Nerve

    Optic nerve is the nerve that links eye and brain, it is like a cable that links camera with television. It is composed of two millions of nervous fibers that, with time and pathologies, can decrease in quantity.

    Macula

    Macula

    Macula is the most central portion of the retina and controls our ability to recognize objects and colors, to read or write, etc, It contains a very small area called central fovea: this is a highly specialized structure that is responsible, in case of very strong brightness, for the best possible visual acuity, color perception and contrast sensitivity. Inside the macula, 3 kinds of cones can be found and everyone is sensitive for a special wavelenght: red, green and blue. The colored images we see, come from the combination of stimula coming from the different cones. Cones are mostly located in the central fovea and in the adjacent retinal portion, where they are placed one next to the other.

    Fovea

    Fovea

    La fovea è la parte centrale della macula, la zona più sensibile della retina. Sprovvista di vasi sanguigni contiene una
    alta concentrazione di fotorecettori soprattutto i coni.

    Retina

    Retina

    Retina is a sensitive membrane, split in three portions: a pigmented layer, a vascular layer, a layer composed of nervous fibers and photoreceptors (6 millions cones and 120 retinal rods). When the focused image falls onto the retina, a series of physical, chemical and electric events happen and, through the optic nerve, the information gets to the visual cortex, where it is corrected and elaborated.

    Cornea

    Cornea

    Cornea is a transparent anatomic structure, non vascularized, rich in nerve endings and is the main optic component in the ocular system. It has five layers; the outer one, called epithelium, is composed of five or six layers of cells of different thickness.

    Pupil

    Pupil

    Pupil is a hole through which light enters the eye. Light coming from the pupil, through the lens reaches the retina. Its size is important for eye surgery.

    Lens

    Lens

    The lens is composed of a little biconvex membranous lens that is around 3,6mm thick . It has the function to adjust focal vergency when objects located at different distances from the eyes are observed by the patient.

    Iris

    Iris

    The iris is a pigmented membrane located behind the cornea and before the lens, it has a central hole (pupil). Its function is to adjust the quantity of light that enters in the eye

     

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