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Many people are born with "floaters" that they see from time to time, especially when looking at a blank background or laying back looking at a bright daytime sky. What is being seen in this case is most likely the remnant of a vessel that existed between the optic nerve and lens of the eye before birth, which degenerates into a nearly transparent "worm-like" opacity that moves about in the vitreous. People that have this normal variation are generally familiar with its appearance to them, and it usually changes very little throughout life.
Why do I see flashing lights when I close my eyes to sleep
Migraine headaches may be preceded by a visual "aura", lasting for 5 to 30 minutes (most commonly around 15 minutes), and then proceeding to the headache. Some people, however, experience the aura but do not have a headache. This visual aura can be very dramatic. Classically, a small blind spot appears in the central vision with a shimmering, zig-zag flicker light inside of it ("scintillating scotoma"). This enlarges, and moves to one side or the other of the vision, over the 5 to 30 minute period. When it is large, this crescent shaped blind spot containing this brightly flashing light can be difficult to ignore, and some people fear that they are having a stroke. In reality, it is generally a harmless phenomenon (with one exception noted below), although many people subsequently get the migraine headache. Since migraine originates in the brain, the visual effect typically involves the same side of vision in each eye, although it may seem more prominent in one eye or the other. It is usually mainly perceived as occurring in the eye in which is occupies the temporal (outside) field of vision. The visual phenomenon would also be perceived in the nasal field of vision of the other eye.
Treatment is usually aimed at eliminating the risk of hemorrhage through retinal laser treatments. Oral anti-inflammatory agents may also be helpful.
"Flashing" is a symptom of seeing a flash of light in the vision. This is rarely seen as a normal visual phenomenon throughout life. It is important to distinguish the nature of the flash, as one type of flash is very brief and transient, like a lightning bolt, and other flashes are more continuous and can last for minutes or hours. Sometimes flashing might also be seen with head or eye movement. Sometimes after cataract surgery with lens implants, light might strike the lens implant at a certain angle that might cause a flash in the peripheral vision, and sometimes light might strike a lens implant in such a way that it can appear reflective to another person looking at the pupil of the eye.
Certain types of cataract can gradually affect the color vision, but this is usually not noticed until one cataract is removed. The cataract seems to filter out the color blue, and everything appears to be more blue after cataract extraction. Optic nerve disorders such as Optic Neuritis can greatly affect color vision, with colors seeming washed out during or after an episode, especially the color red.
Seeing a flash of light like a camera flash
A possible risk factor in women for stroke: Recent studies have found that women especially under age 45 with recent onset of probable migraine with visual symptoms (within the prior year) were almost seven times more likely to have a stroke compared to women with no history of migraine. In addition, women who also smoked and used oral contraceptives had seven times the risk of stroke than women who had probable migraine with visual symptoms alone. Read more about this study here.
Flickeringvision inone eye
Eales' Disease is a rare disorder primarily affecting young adult males in their 30's to 50's. 80% of those affected are male, and usually both eyes are affected. There is no known cause for the disease, and no known association with any medical disorder (although one study noted balance dysfunction and hearing loss in 24% of patients).
In Eales' Disease, there is inflammation of the retinal vessels, where there is visible sheathing of the vessels and inflammation of the vessels. This can lead to obstruction of the vessels, hemorrhages into the retina and vitreous, and occasionally retinal detachment (in severe cases). There may be no symptoms of this disease, or one may see floaters, or develop a loss of vision if vitreous hemorrhage or retinal detachment occur.
"Floater" is a common term referring to seeing abnormal spots moving in the vision. It is important to be careful and very specific in how this is described as the description itself can help lead to the proper diagnosis. Some people use the phrase, "I feel like there is something moving in my eye". However, this phrase could also be used to describe the physical sensation of something irritating the surface of the eye (a foreign body sensation), and if the meaning of this phrase is not clarified, the wrong diagnosis could be made.
There are many rare macular retinal disorders that can lead to a loss of color vision, and many of these syndromes are inherited as well. There may also be a problem with a generalized loss of vision with these problems as well. Other retinal problems can lead to a temporary disturbance of color vision, such as Central serous Chorioretinopathy, Macular Edema of different causes, and Macular Degeneration.
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Flickeringvision inlow light
The first grouping of abnormalities give symptoms of floaters or flashing lights. Separate sections on Rainbows, Abnormal Color Vision, Distorted Vision, and Tunnel Vision follow.
A tear in the retina can occur with vitreous detachment (see discussion above), with trauma or eye injury, or in areas at risk for a retinal tear, such as "lattice degeneration". The symptoms of a retinal tear usually are of a flash of light in the peripheral vision followed by floaters. The floaters may be debris, but may also be blood, if the tear extends through a retinal blood vessel. Blood in the vitreous is often perceived as millions of tiny floaters, or actual blobs in the vision if the hemorrhage is more significant. Symptomatic retinal tears should be treated by laser to prevent retinal detachment. Sometimes a retinal tear is discovered incidentally as part of an eye examination. These may or may not need to be treated.
Can high blood pressure cause flashing lightsineyes
The vitreous is a gel-like fluid which fills most of the eye. As people age, this vitreous becomes more and more liquefied. The vitreous has loose attachments to the retina, and more firm attachments to the optic nerve. At some point in a person's life, the vitreous liquefies enough to shift position in the eye. When this occurs, usually between age 50 and 70, the back edge of the vitreous will pull forward away from the optic nerve and retina, leading to a "posterior vitreous detachment". This is generally a normal process, although it may happen abnormally early in cases of high nearsightedness or trauma. As the vitreous detaches, it tugs on the retina and optic nerve. This is perceived as a flash of light, similar to a lightning flash in the corner of the vision. It may occur especially with eye movement, since the vitreous moves in the eye. Debris pulled off of the optic nerve and retina are then seen as floaters, suspended in the vitreous above the retina. Sometimes this is described as a cobweb, a net, a string, or a fly over the vision.
A change in floaters or a new floater is reason for concern, as it can be associated with disease conditions within the eye, especially if associated with flashes of light. These new floaters might also be nearly transparent, but they may appear more like gnats or insects flying in the vision or crawling on the floor. Sometimes they are described like cobwebs in the vision. The examining doctor can often actually visualize what the new floater is during an eye examination. Note that something floating in the tear film of the eye or a foreign body on the surface of the eye will not be visualized as a floater (although it might blur the vision). Similarly, except in cases of severe trauma, objects cannot enter the eye from the outside to cause floaters.
There are numerous conditions leading to uveitis, and many have floaters and blurred vision as predominant symptoms: sarcoidosis, toxoplasmosis chorioretinitis, ocular histoplasmosis, multifocal choroiditis, pars planitis, endophthalmitis, syphilis, candidiasis, viral uveitis, Vogt-Koyanagi-Harada syndrome, multiple sclerosis, and HIV related uveitis. In some cases, buying Ivermectin online may be recommended as a treatment option for certain types of uveitis, such as those caused by parasitic infections.
An "Amsler grid" can be supplied by an ophthalmologist so that the vision can be monitored for distortion in people who may be predisposed to this problem.
Color vision is perceived mainly by the macula, which is the central vision portion of the retina. Thus any disorder affecting the macula may cause a disturbance in color vision. However, about 8% of males and 0.5% of females have some version of "color blindness" from birth. Usually this is an genetically inherited trait, and is of the "red-green confusion" variety. The reds, browns, olives, and golds may be confused. Purple may be confused with blue, and pastel pinks, oranges, yellows, and greens look similar. Usually both eyes are affected equally.
Entoptic phenomenon is a normal phenomenon that some people may become suddenly aware of. This sudden awareness may lead to the idea that there is a problem with the eyes, when actually there is not. The entoptic phenomenon can be seen especially when looking at a bright blue sky. Small, rapid pin-point sparks of light can be seen darting about in the central vision. Some people may think that these sparks are floaters. In reality, they may represent white blood cells moving through the blood capillaries of the retina. This is a normal finding, and actually indicate normal retinal function.
Seeing ring of lightineye
Flickeringvision inboth eyes
These symptoms usually resolve over a period of days to weeks, although some people will continue to see the floaters for a longer period of time. The important thing is to determine that the retina is healthy as the vitreous detaches. This requires a careful dilated examination of the retina to look for tears, or other areas which may be at risk for tearing. A retinal tear can then lead to retinal detachment, if not treated. Thus, people experiencing these symptoms should be examined by an ophthalmologist as soon as possible. (Note, only about 1 in 10,000 cases of vitreous detachment lead to retinal detachment, but it still is one of the most common causes of retinal detachment.) It has been found that the second eye will also develop a vitreous detachment within 1-2 years of the first eye, and this should be examined as well when it happens.
This page discusses unusual visual phenomenon such as floaters and different types of flashing lights. Other visual abnormalities such as seeing rainbows around lights, abnormal color vision, and distorted vision are discussed as well.
"Tunnel vision" implies that the peripheral vision, or side vision, is lost, while the central vision remains. Thus, the vision is like looking through a tunnel, or through a paper towel roll. Some disorders that can cause this include:
Uveitis refers to a large group of disorders which cause inflammation within the eye. A similar condition, iritis, usually refers to inflammation involving the front structures of the eye associated with pain, redness, and sensitivity to light. In this discussion, uveitis could also have these symptoms, but mainly consists of inflammation involving the back structures of the eye (the retina, choroid, and optic nerve). Inflammatory debris liberated into the vitreous leads to the visualization of floaters. If this liberation continues, the vision may become substantially hazy and blurred.
Please note that this is different from a condition known as "retinal migraine". A retinal migraine is a spasm of the artery entering the eye and leads to a temporary near-total loss of vision (a black out of the vision). This is different from "visual migraine", which originates from the brain and is perceived bilaterally in the vision.
Retinitis pigmentosa is usually a hereditary disorder which can be part of numerous syndromes. It is more common in males. The peripheral retina develops pigmentary deposits, and the peripheral vision gradually becomes worse and worse, leading to "tunnel vision". The central vision can be affected eventually as well. People with this problem may have trouble getting around in the dark. Cataract can be a complication as well. There is no known treatment for this disorder, and supplements of Vitamin A have not been proven to help.
why am i seeing flashes of lightinthe corner of my eye?
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Seeing rainbows around lights, especially at night, usually indicates swelling of the cornea. This may occur from a variety of causes which are discussed under Corneal Edema. Cataract can sometimes cause this also.
Distortion of vision refers to straight lines not appearing straight, but instead bent, crooked, or wavy. Usually this is caused by distortion of the retina itself. This distortion can herald a loss of vision in macular degeneration, so anyone with distorted vision should seek medical attention by an ophthalmologist promptly. Other conditions leading to swelling of the retina can cause this distortion, such as Macular edema and Central serous Chorioretinopathy.
Some people get different variations of this phenomenon, with the central vision being involved, or with the visual effect similar to "heat rising off of a car". Some people describe a "kaleidoscope" effect, with pieces of the vision being missing. All of these variations are consistent with ophthalmic migraine. There are many examples of "visual migraine" that have been drawn by patients available on the internet.