Regeneration of damaged RGC axons was not considered a possibility until when Berry et al. The emerging science — obtained from experimental models — is that if axon function can be repaired early enough, either by reducing intraocular pressure IOP -related damage on the axon or by removing the influence of metabolic pathological changes, loss of tissue in glaucoma can be avoided.
More recent scientific studies have shown that this same effect might hold true for human glaucoma. The optic nerve and retinal neuronal cells are integral components of the central nervous system and, as mentioned previously, their capacity to regenerate in adult tissues is severely limited.
As well, axon degeneration in the optic nerve is not confined to a single area. This means that regenerative strategies potentially need to replace entire lengths of axons or repair axons at multiple points of damage; a significant challenge for developing practical approaches to regenerate fibres of RGCs.
So to progress regenerative science to a point where we can overcome the effects of heightened damage imposed by IOP and partially improve vision in glaucoma patients, we must develop regenerative therapies that consider many challenges.
One of them is the necessity to maintain connections between retinal cells and the corresponding neurons in the visual centres of the brain. Not surprisingly, our visual system is very specific in its connections. Although most axons in our brain travel from the eye to special subcortical structures, some target other areas of the brain; all of which combined present us with a full picture of the world around us.
As well, cells throughout our visual system map to each other in very specific ways allowing us to receive the highly-organized information we need to see. The richness of our visual experience depends on accurate maintenance of these maps, and we expect regenerative therapies will need to capture the need for restored retinal cells to connect to their corresponding neurons in the brain.
Although significant progress has been made in recent years to better identify and understand regenerative therapies that can help restore vision in patients with optic nerve damage, like those with glaucoma, much more work is needed to translate this emerging science to readily-available treatment therapies. Our Restore Vision Clinic in Berlin has significant experience in both improving vision in glaucoma patients and in slowing down their loss of vision - both of which are achieved without structural regeneration of the damaged optic nerves.
Given our scientifically-proven treatments and clinical successes, we are confident in saying that functional restoration of vision is possible today without regeneration. Damaged optic nerve and retinal cells still have a capacity to provide more function. During optic neuritis inflammation can cause damage to the protective sheath myelin surrounding this nerve and the nerve itself. It can effect one optic nerve or both optic nerves at the same time. Vision symptoms from optic neuritis can include blurring, blind spots or complete loss of vision.
You also may notice distorted vision, reduced color vision and pain when you move one or both eyes. These types of symptoms may precede vision loss due to optic neuritis. The term optic neuropathy more generally describes optic nerve abnormalities or damage.
This damage could be from blocked blood flow, certain medical conditions or toxic exposure. Optic neuritis is one specific cause of an optic neuropathy. Optic neuritis can occur in anyone, but usually occurs in adults younger than 45 and affects more women than men.
The condition is common in people who have multiple sclerosis MS , which occurs when the body's own immune system attacks and destroys protective nerve coverings. Besides affecting eyesight , related nerve damage in MS can lead to loss of mobility and sensory functions, along with other debilitating conditions. Image of the back of a healthy eye, where the optic nerve is located. Hereditary, nutritional, and toxic optic atrophies.
Philadelphia, PA: Elsevier; chap 9. Prasad S, Balcer LJ. Abnormalities of the optic nerve and retina. Bradley's Neurology in Clinical Practice.
Updated by: Franklin W. Editorial team. Optic nerve atrophy. These may include: Brain tumor Cranial arteritis sometimes called temporal arteritis Multiple sclerosis Stroke There are also rare forms of hereditary optic nerve atrophy that affect children and young adults.
Exams and Tests. The exam will include tests of: Color vision Pupil light reflex Tonometry Visual acuity Visual field side vision test You may also need a complete physical exam and other tests.
Rarely, conditions that lead to optic atrophy may be treatable. Outlook Prognosis. Optic Nerve Head Drusen is another condition that causes damage to the optic nerve. Also known as, Optic Disc Drusen, the condition occurs when pockets of mucoproteins and amino sugars calcify in the optic disc. Another condition that results in optic nerve damage is Optic Nerve Hypoplasia , which occurs due to the underdevelopment of the optic nerve.
The optic nerve appears to be abnormally small in this condition due to underdevelopment. Vision loss may occur with optic nerve hypoplasia. Tumors in the brain, especially those in the pituitary gland of the eye, can also cause damage to the optic nerve. Trauma and injury to the eye or the brain can also affect the optic nerve, resulting in deteriorating vision.
To learn more about diseases and conditions that can cause damage to the optic nerve, click here. Some people will experience pain because of the damage. A person with optic nerve damage will experience mild to severe pain when they move their eyes or while resting.
Vision loss is a common occurrence with optic nerve damage. Since the optic nerve links the brain with the eyes, the visual acuity is affected, resulting in eventual vision loss. Loss of color vision is another occurrence with optic nerve damage. A person with optic nerve damage will partially suffer from loss of color vision. Loss of visual perception will also occur if the damage to the optic nerve becomes severe, as the eyes are no longer able to perceive the surroundings.
Unusual symptoms include numbness or weakness of the limbs, which may be a result of a neurological disorder. Unfortunately, once damaged, the optic nerve cannot be repaired since the damage is irreversible.
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