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The optic nerve is a sensory nerve that originates in the retina and is responsible for sending nerve impulses to the brain for it to interpret and transform into images.

It is indispensable for the vision. Although the entire ocular structure works correctly, a failure in the optic nerve is able to compromise vision completely.

En Área Oftalmológica Avanzada We explain, then, what is the optic nerve and what are its functions. 

optic nerve

What is the optic nerve?

The retina is a sensitive tissue that transforms light into nerve impulses. These signals are sent by the optic nerve to the brain to be processed and transformed into images.

Without the optic nerve, it is impossible for a person to see. 

The optic nerve originates in the layer of retinal ganglion cells and is made up of more than 1,2 millions of axons that are attached in the form of a corsage in the back of the eye.

It can measure up to 5 centimeters and when it leaves the eyeball it is covered by meningeal sheaths and cerebrospinal fluid until it reaches the central nervous system. 

Its duties?

The main function of the optic nerve is to transport the electrical impulses created in the retina to the brain for the images to form correctly.

As it does? To understand it you have to know the light path in the ocular structure

Light enters the eyes through the cornea and is projected on the retina. In the retina, the photoreceptor cells are responsible for transforming the light received into electrical impulses that will travel through the nerve.

The images are formed thanks to the participation of two photoreceptor cells: the cones and the canes. The cones are responsible for color perception and the rods are responsible for let's see shapes in low light conditions

Once the optic nerve receives the information, it sends it to the central nervous system where it is interpreted and transformed into the images we receive.

This whole process occurs in thousandths of a second and can be interrupted if the optic nerve presents the slightest lesion in its nerve fibers. 

Optic nerve diseases

El damaged optic nerve or inflamed represents a major problem for eye health. Sometimes a cure can be found to recover some of the vision lost due to a damaged optic nerve, but in others the damage can be irreversible.

Let us know below what are the diseases that can impair the function of the optic nerve. 


It is a set of diseases that degeneratively affect eye health. Glaucoma occurs due to intraocular pressure elevation which directly affects the function of the optic nerve.

El glaucoma It is one of the main causes of blindness in the world. 

Optic neuritis

Infections and diseases associated with the immune system, such as multiple sclerosis, can cause inflammation of the optic nerve, causing ocular pain, and compromise its correct functioning.

In some cases, the optic neuritis It can occur without apparent cause. 

optic nerve atrophy 

Lack of blood flow can cause nerve fiber death and nerve atrophy. 

optic nerve drusen

Our optic nerve drusen they are the accumulation of protein and calcium pockets in the structure of the optic nerve.

En Área Oftalmológica Avanzada We are experts in the care and treatment of diseases of the optic nerve. If you need one ophthalmologic review complete, do not hesitate to schedule an appointment with our specialists: we will attend you as soon as possible! 

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Optic nerve
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Optic nerve
The optic nerve fulfills an essential function for vision. We tell you what it is and what diseases are associated with it.
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Área Oftalmológica Avanzada
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