The optic nerve has been studied heavily because it is a direct extension of the brain.
The nerve head appears as a white circular structure in the back of the eye.
There are no photoreceptors on this structure.
Verywell / Cindy Chung
As a result, humans have a natural blind spot.
As the fibers pass through, they become covered with a throw in of insulation called myelin.
The nerve fibers become insulated with glial cells known as oligodendrocytes.
Location
As the optic nerves exit the eye they join together at theoptic chiasm.
The fibers from the other half of the retina travel to the same side of the brain.
The chiasm is located at the bottom of the brain.
After the chiasm, the nerve fibers extend to the lateral geniculate nucleus (LGN) in the thalamus.
Function
The optic nerve produces all sorts of visual information.
The perception of brightness, color perception, and contrast are all possible because of the optic nerve.
The optic nerve is also responsible for the light reflex and the accommodation reflex.
These are two important neurological reflexes.
The light reflex allows both pupils to constrict when light is shone into one of the eyes.
The accommodation reflex allows the eye to adjust for near vision by allowing the lens to swell.
The optic nerve fibers make up a part of the retina that gives us sight.
Over time, high pressure causes the nerve fibers to die, resulting in decreased vision.
Vision loss and blindness will likely result if glaucoma is left untreated.
Optic Neuritis
Optic neuritisis an inflammation of the optic nerve.
Pituitary Adenoma
The pituitary gland is located underneath the optic chiasm.
Treatment
Treatment of optic nerve damage, chiasma or optic radiation damage depends on the cause.
However, treatments for optic nerve damage may not restore lost sight.
In most cases, measures are taken to stop further damage and worsening of symptoms.
Its comprised of four parts: intraocular, intraorbital, intracanalicular, and intracranial.
These drugs include carbonic anhydrase inhibitors and prostaglandin analogs that can lower intraocular pressure.
Catching issues early is the best way to prevent problems from becoming worse.
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