Optic nerve what is it

Constant eye strain causes squinting, severe discomfort and headaches, just as with blurry vision. Hazy or foggy vision can also be indicative of numerous acute or chronic conditions, both common and severe, such as glaucoma, cataracts, and acute optic nerve damage.

It is one of the most typically reported symptoms among those suffering from problems with their eyesight, and can be distinguished during routine eye examinations. Optic nerve damage often causes the loss of central vision which can be total absolute or partial relative. In clinical practice this is defined as a scotoma blank area in field of vision.

Scotoma is caused by the damage of central fibers of the optic nerve, and frequently occurs in cases of optic neuritis and other autoimmune or inflammatory processes. Major complaints include severe difficulties with straight-ahead sight due to central vision being blurry, foggy, or entirely absent in the form of a blank area as in the case of total scotoma. In the early stages of developed scotoma, another common complaint includes difficulties in distinguishing colors, especially between light or dark colors.

Most noticeable defects occur in the bottom of the field of vision, or the nasal or temporal parts. Depending on the severity of the case, patients describe their condition as partial loss, where the field of vision is not completely lost, but rather becomes low-functioning, with the individual experiencing hazy or blurry vision on the periphery. In severe cases peripheral vision is entirely absent. Extremely severe conditions such as advanced or terminal glaucoma leave only limited central vision preserved.

Loss of peripheral field of vision, and in many cases low-functioning field of vision, can make common activities like driving a car or walking difficult or impossible. Individuals suffering from loss or lack of field of vision often report difficulties seeing properly in low or dim light, as well. Problems with field of vision often stem from different types of optic neuropathy or damage of visual system in the brain due to stroke or head trauma.

Patients suffering from field of vision loss commonly seek the help of low vision specialists to determine ways that peripheral vision can be corrected or compensated by special lenses or devices or visual exercises. The cause and severity of the loss or lack of field of vision generally determines the effectiveness of various corrective treatments or rehabilitation approaches.

Glare: Glare is the difficulty in vision produced by bright lights when the luminance is much greater than the luminance to which the eyes are adapted. Due to excessively bright light, poor visibility and poor visual performance is observed. In addition, recovery time from bright lights is longer than typically experienced. Glare is generally caused by an inability of photoreceptor cells in your retina to focus light received from your environment, and also depends on damaged retinal ganglion cells in the case of optic neuropathy.

Like many other symptoms of neuropathy, this can cause one to squint while attempting to focus, causing painful eyestrain and headaches. Finally, glare can be caused by any condition affecting the retina and photoreceptor cells, and can be indicative of serious eye conditions. Objects appear darker and less clear than they are in actuality, which can also make them appear blurry, hazy, or lacking proper contrast. This symptom is often caused by optic neuritis, or inflammation of the optic nerve and the fibers of which it is composed.

Optic neuritis can be caused by a wide array of autoimmune conditions and inflammatory diseases. The ability to adapt to darkness is determined by the ability of photoreceptors rods and cones in the retina to respond properly to lower levels of light after having been previously exposed to brighter light.

Painful Eye Movement: Eye pain is a general term used to refer to pain and discomfort in any region in or around the eye. Like any kind of pain, eye pain ranges from the barely discernible to severe and debilitating, and yet the severity of eye pain is not necessarily or automatically indicative of the seriousness of the underlying cause s.

Likewise, eye pain is often described in similar terms to pain felt elsewhere, with individuals reporting muted, dull, burning, throbbing, piercing, or sharp pains, among other common descriptors. However, eye pain related to optic neuritis is almost always most severe when eye movement occurs.

Painful eye movement can be caused by a host of conditions and illnesses, including a foreign object lodged in or near the eye, optic neuritis, multiple sclerosis, fungal infection, head trauma, and corneal and other abrasions. Any pain caused by optic neuropathy requires timely medical intervention to prevent further damage caused by the specific underlying cause. Treatment will, as always, depend on the determination of such cause or causes.

In addition to these sensations, dry eye can also be concurrent with redness, soreness, itchiness, aching, irritation, and blurred vision. While dryness of the eye is a commonly reported symptom, persistent lack of eye lubrication can lead to a severe and sometimes permanent issue of the eye, and is therefore a condition that could very well be indicative of a far more urgent situation, which requires a comprehensive evaluation.

In latter cases, simple remedies such as eye drops may be insufficient to treat the symptom and its underlying cause s sufficiently. Because dry eye can be caused by such a variety of conditions, any prolonged experience of this symptom requires timely attention and the attention of an eye care professional.

Similarly to dry eye, redness of the eye can be anywhere from mild to severe and indicative of a variety of underlying causes. Likewise, it can be accompanied by a number of other conditions, such as watering of the eye, dryness, sensitivity to light, pain, and blurred vision.

While redness of the eye or eyes is not always an indicator of a serious condition and is often temporary or simply environmental dust, pollen, and pollution, for example , this is not always the case. More serious causes of eye redness are ulcers, infections, injuries, and trauma. Redness also often accompanies or results from eye surgery, and while this is common, it may also signal a larger issue or more severe cause occurring as a negative outcome from that surgery. For these reasons, any prolonged period of eye redness should be promptly treated by an eye care professional.

Glaucoma: Glaucoma is one of the most common causes of optic nerve damage and subsequent vision loss, which is often the first sign of the condition due to the fact that, generally, glaucoma causes no pain until the condition has advanced considerably. One of the leading causes of blindness worldwide, glaucoma is commonly related to ocular hypertension, or increased pressure within the eye. There are two subtypes of glaucoma associated with high intraocular pressure— - open-angle glaucoma and closed-angle glaucoma, the former being the far more commonly occurring variety.

Open-angle glaucoma progresses slowly, and, again, generally produces no pain. However, the end stages of developed terminal glaucomatous optic nerve damage leads to total blindness. Some glaucoma patients develop typical symptoms of eyesight loss where elevated pressure cannot be revealed, which is generally known as normal-tension glaucoma.

Glaucoma is usually diagnosed during an eye exam by using instruments that test the intraocular pressure within the eye, field of vision, and thickness of the optic nerve. Once diagnosed, proper treatments, such as surgery, medications, specialized eye drops, or laser procedures, will be administered.

The proper glaucoma management for each case of the condition is often determined by success in lowering of intraocular pressure, the speed of glaucomatous optic nerve damage, and the timing of vision loss. Lack of Blood Supply Ischemic Optic Neuropathy : Ischemic optic neuropathy is a condition in which a lack of blood supply results in damage to the optic nerve and subsequent loss of vision. The majority of all ischemic optic neuropathies are anterior ones AION , meaning blood vascularization in the optic nerve occurs close to the eyeball.

This is usually due to inflamed arteries, or arteric AION. Full vision loss occurs in some cases but is exceedingly rare. Three major causes of NAION have been determined: first, an optic disc that is too narrow to accommodate the optic nerve from which it emerges; second, sleep apnea syndrome and third, various cardiovascular conditions including high cholesterol, diabetes, and hypertension.

However, the aforementioned fall in blood pressure overnight is the most common cause. Patients are generally diagnosed via an eye examination and consideration of other health factors and predispositions.

Treatment of the condition has often been difficult, although some specialized treatments using certain types of steroids can be partially successful. Eye or Head Trauma: Any type of trauma or injury to the eye or severe head trauma in general can cause optic neuropathy. Concussive blows to the head and traumatic brain injury can lead to vision problems including loss or reduction of field of vision, double vision, blurred vision, sensitivity to light, and pain during eye movements.

Treatments for concussions and brain injuries vary based on the type and degree of symptoms. Inflammation and Autoimmune Conditions: Inflammation of the optic nerve, or optic neuritis, due to autoimmune conditions will often cause optic neuropathy and severe vision problems.

Two of the most common conditions responsible for vision loss are multiple sclerosis and neuromyelitis optica. Multiple sclerosis or MS is an autoimmune condition that occurs when nerve endings, including the optic nerve, are damaged due to the immune system attacking the myelin - the substance which is used to cover the trunks of the nerves.

MS is one of the most common causes of optic neuritis, and the detection of optic neuritis during eye exams is often an early indicator of the condition.

Damage to the optic nerve causes a wide variety of symptoms from blurry or hazy vision, defects of central visual field, dimming of the eyesight and low contrast. Neuromyelitis optica is another autoimmune disorder in which the immune system primarily attacks the optic nerve, spinal cord, and in some cases, the brain. Its effects on vision are similar to MS, causing optic neuritis and loss of vision.

However, neuromyelitis optica, unlike MS, generally has no progressive stage, but rather occurs in repeated acute attacks that can often be even more devastating than those occurring with MS.

Optic neuritis can be detected using standard eye exams like visual field tests or imagining of the optic nerve and more specialized exams like MRI or comprehensive blood tests. Treatment for the condition generally centers around oral steroids which serve an anti-inflammatory purpose. Non-Development of the Optic Nerve Optic Nerve Hypoplasia : Optic nerve hypoplasia or ONH is a congenital condition resulting from the non-development or underdevelopment of the optic nerve, where the fibers making up the optic nerve either fail to develop or develop incompletely.

ONH most commonly affects both eyes, however it can also be present in one eye only. Depending on the severity of the case, NHO can affect vision minimally or drastically, with latter cases involving severe loss of vision and intense difficulties perceiving light due to a reduced numbers of optic fibers. ONH is diagnosed via examination conducted by an ophthalmologist, where the optic nerve will appear structurally abnormal and smaller than a healthy nerve. Treatment of ONH is difficult, and often includes typical assistance for the visually impaired along with treatment of other non-visually related symptoms of the condition.

Brain Tumors: Brain tumors can often cause compression of the optic nerve leading to varying degrees of vision loss and different forms of visual impairment. The compression primarily causes local ischemic damages in the optic nerve leading to optic nerve atrophy and disruption of the visual pathway, essentially cutting off the relaying of visual signals from the eyes to the brain.

The most typical clinical signs brain tumors are damages to and defects in the field of vision, which can be partial in some areas. In the most severe cases, compete blindness occurs. One such example of compression occurs in the form of a pituitary adenoma, a type of tumor occurring on the pituitary gland. This form of tumor while growing applies pressure to the optic nerves where they are crossed at the optic chiasm.

For this reason, defects of peripheral vision are progressive, starting from the very periphery and slowly damaging more and more side vision. In the end stages, half of the field of vision is gone, a condition better known as bitemporal hemianopia. Elevated Intracranial Pressure: Intracranial pressure, or pressure inside the skull, can also cause optic neuropathy. While increased pressure can occur for a number of reasons, it is often caused by brain tumors or conditions such as hydrocephalus, a condition in which cerebrospinal builds up within the brain.

Both hydrocephalus and tumors are generally treated with surgery to reduce a variety of negative symptoms, including vision-related symptoms including blurry vision, double vision, and other visual impairments and disturbances that vary in severity. Infections and Related Diseases: Different infections can cause optic nerve damage as well, depending on the type and location. Sinusitis commonly known as a sinus infection , for example, is the inflammation of the sinuses, areas surrounding the nasal cavity that are filled with air.

When these become inflamed, severe facial pressure often occurs, particularly between and behind the eyes, causing severe pain and making vision difficult at times. Generally, blurring of vision occurs, although in severe and chronic cases optic neuropathy can occur as well, leading to loss of vision.

Diseases such as lupus and sarcoidosis are other examples of diseases that may have dire effects on vision, particularly the optic nerve. Such infections and diseases are often treated with anti-inflammatory medicines such as steroids, or through antibiotics. Toxins: Toxins, particularly alcohol, tobacco, and drugs can also cause optic nerve damage and lead to partial or severe loss of vision. For example, prolonged alcohol use can cause toxic optic neuropathy with long-term loss of central vision, color deficiency, and general loss of vision.

Many of these symptoms and conditions can cause permanent damage and threaten the future integrity of your vision. If a confirmation of optic nerve damage is made by a professional, make an appointment as soon as possible at the Fedorov Restore Vision Clinic , where you may receive vision restoration therapy. Naturally, any patient suffering from optic nerve damage wants to know how and by what methods their condition can be managed and treated, and whether or not the damage suffered can be cured outright.

When it comes to optic neuropathy atrophy of the optic nerve , this is often a complex issue. Here, we will examine existing forms of management and possible cures.

The treatment of optic nerve damage largely depends on the underlying cause. Methods of management and treatment are often centered on the prevention of further damage to the nerve, as damage already suffered unfortunately can rarely be reversed.

In other words, the focus of treatment is often on stabilization of symptoms and halting the progression of a given condition. Healthcare providers also encourage those with optic nerve damage to maintain the healthiest possible lifestyle, particularly when it comes to eating a balanced diet with nutrient-rich foods that may help stabilize vision along with other treatments.

Because the management of optic nerve damage depends largely upon early detection and preventative methods, it is essential that anyone suffering from vision problems see their eye care specialist immediately. Unfortunately, at the present moment there are no known ways to reverse optic nerve damage which are offered for public use. Research on the subject has increased considerably in recent years, with researchers testing experimental methods in laboratories, particularly on mice.

In addition, it has been found that certain animals, some mammals for example, are able to regenerate the axons stemming from their retinal ganglion cells RGCs , which are necessary to carry visual information to the brain. Similarly, researchers have found that certain lower vertebrates can spontaneously regenerate their optic nerves and repair their sight completely. Doctors and researchers hope that by studying these phenomena, it might be possible to translate regenerative processes to human beings.

Here are a few examples of the experimental methods used in attempts to reverse optic nerve damage, some of which have proved partially effective in laboratory settings only :.

These are just a few of the methods being tested and modified by researchers all over the world. While considerable advancements have been made in attempts to repair and reverse optic nerve damage, none of these have proven significantly reliable and have been confined to the laboratory. However, there is reason for hope in other advanced approaches as well.

It is well known that the optic nerve connects the eye with the brain, and unfortunately it remains an issue in modern medicine that there is a therapeutic break between ophthalmologists who do not treat optic nerve diseases because it's a part of the brain and neurologists who do not treat the loss of vision, even when caused by optic nerve disorders. Fedorov Restoration Therapy is unique in that it is an interdisciplinary approach that bridges ophthalmology and neurology, eye and brain, combining the two in order to achieve breathtaking results for visually impaired patients whose vision loss relates to medical conditions of the optic nerve.

It is also unique in being a completely non-invasive, non-surgical method that improves and restores vision naturally with stable results and with no risk of side effects.

While it is important for prospective patients to keep in mind that Fedorov Restoration Therapy cannot actually regenerate the optic nerves or replace damaged cells, it can drastically improve vision by achieving two significant outcomes: 1 an increased functioning of pre-existing preserved cells on the retina, and 2 enhanced activity and flow along the whole visual pathway from the optic nerves to the visual cortex.

This cutting edge Fedorov Therapy is able to help patients suffering from many different types of visual complaints caused by a vast range of optic nerve diseases, some retinal dystrophies, damages to the visual pathway or cortex in the brain, and in cases of amblyopia.

Fedorov Restoration Therapy is a painless, straightforward process designed to improve the function of retinal cells and the entire of the optic nerve.

Optic nerve damage disrupts the flow of information from the eye to the brain, often causing a variety of negative symptoms and eventually leading to lost or impaired vision. FedorovRestoration t Therapy employs an application of weak electrical current pulses which stimulate partially-damaged retinal cells and improve the conductivity of signals to the brain in order to enhance a traveling of visual signals along the affected optic nerve.

While attending the clinic, patients undergo comprehensive exams in order to determine the degree of their vision loss and to set a baseline by which post-therapy results can be measured. They will go through the testing of subjective vision visual acuity, contrast vision, colour vision , detailed visual field exams, modern analysis of optic nerve and retina structure based on OCT eye imaging, electrophysiological evaluation and an EEG electroencephalogram, which measures brain waves during this evaluation.

After these tests are conducted, patients are ready for the treatment to be administered. Fedorov Restore Vision Clinic provides outpatient treatment during which patients attend the clinic daily excluding weekends over a two week period for therapeutic sessions lasting approximately two hours a day. Restoration treatment is achieved by the administration of alternating current through a series of electrodes attached near and around the eyes.

This current passes through the eye and along the optic nerve to the brain. Once therapy is completed patients will undergo the same exams that were conducted during their preliminary visit. At the time these are completed, results obtained from the therapy will be discussed during a discharge discussion.

Ultimately, the major goal of Fedorov Therapy. In fact, in before-and-after surveys conducted with those treated, the vast majority of patients report improved everyday activities, regained social functioning and increased independence, directly leading to a higher quality of life. If you or a loved one are experiencing vision problems, especially caused by optic nerve damage, Fedorov Restoration Treatment might be the right treatment for you.

Recognizing its unique place in the field of vision restoration, Fedorov Restore Vision Clinic's mission is to qualify for treatment only those eligible patients who can benefit the most from Dr.

Achieving this goal would not be possible without obtaining sufficiently detailed feedback from the clinic's clients: visually impaired patients.

Given this objective, a comprehensive survey was developed to provide an accurate assessment of how successful the clinic's efforts have been over time. This allows Dr. This helps Dr. Fedorov has received. Many of the responses may be close to what you are feeling at this moment in your own life. Understanding what types of symptoms and complaints former patients have shared and expressed, which could be similar to your own, may help you determine whether or not Fedorov Therapy is right for you.

While there are several common complaints, patients have experienced a wide variety of core symptoms before undergoing treatment. There are four main symptoms that are most common among patients seeking treatment at the clinic, the first two of which are disturbances in central vision and a partial or complete lack of peripheral vision. These two symptoms are grouped together here because they are often experienced together, according to patient reports.

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This high pressure compresses the optic nerve and causes cells to die. It is referred to as atrophy of the optic nerve. Although the optic nerve is part of the eye, it is considered part of the central nervous system. The superior oblique is a fusiform spindle-shaped muscle belonging to the extraocular group of muscles. It originates near the nose.

Along with the…. The ophthalmic artery branches off from a major group of blood vessels in the head and neck known as the internal carotid arteries. The ophthalmic…. The optic chiasm or optic chiasma is an X-shaped space, located in the forebrain, directly in front of the hypothalamus.

Crucial to vision, the left…. The orbicularis oculi muscle is one of the two major components that form the core of the eyelid, the other being the tarsal plate.