what causes sudden blurry zig zags in the shape of a crescent in the peripheral vision of the eye?
356001
It's a visual migraine.  I get them too. Painless, fortunately. Mine looks like a neon alligator flashing on and off.  My sister has them, too, and she said that if you try to examine the zig zags, you will see they are made up of images of items that you just looked at.  She's right! I tried really looking at it and the zig zags do contain images.  Interesting in a wierd way.
964323
I have floaters. It has something to do with your retina. Should you start noticing many more just out of the blue, blurring vision, peripheral vision fading or blasts of bright light in your vision then you should get to a doctor quick b/c that could mean that your retina is detaching. Look it up in the search engine for more info.
929139
That's a little scary... blurred vision is a sign of REALLY high blood pressure.
695164
It might be conjunctivitis.
23047
I've never had them, but floaters that are just simply annoying, treatment is not necessary.  If they are so dense and numerous that they affect your vision, then you should see your doctor.  If you suddenly see new floaters, or eye floaters accompanied by flashes of light or peripheral vision loss, it could indicate serious conditions such as diabetic retinopathy; vascular abnormalities such as retinal hemorrhages or carotid artery disease, or the beginning of a retinal detachment.  In this case you should also see your doctor.
273966
We do not know exactly why this happens, but it might reflect a "crossing" of pathways in the brain, between the normal reflex of the eye in response to light and the sneezing reflex.\n\nClick below for a FULL explination
358325
Most spots and eye floaters are merely annoying but harmless when they temporarily enter the field of vision, and many fade over time. People sometimes are interested in surgery to remove floaters, but doctors are willing to perform such surgery only in rare instances.\n\nIf you suddenly see new floaters, or eye floaters accompanied by flashes of light or peripheral vision loss, it could indicate serious conditions such as diabetic retinopathy; vascular abnormalities such as retinal hemorrhages or carotid artery disease, or the beginning of a retinal detachment. The retina can tear if the shrinking vitreous gel pulls away from the wall of the eye. This sometimes causes a small amount of bleeding in the eye that may appear as new floaters. You should see your eye doctor immediately
148010
There are many possible physical causes for the diffraction.  Eyes half shut: your eyelashes.  Driving: windshield wiper streaks (visible streaks are at right angles to wiping streaks).  Possibly cataracts or scarring from laser eye surgery.
894122
This is a list I found of causes of blurry vision.  I have put a ** next to the ones that might be found on CT or MRI scans of the brain.\n\n"The following medical conditions are some of the possible causes of Blurred vision. There are likely to be other possible causes, so ask your doctor about your symptoms. \n\nRefractive eye conditions \nMyopia \nNear-sightedness \nPresbyopia \nFar-sightedness \nUncorrected vision disorder \nWrong eyeglasses \nEye irritation (see Eye symptoms) \nDry eyes - may cause blurred vision; see the many causes of dry eyes \nEye conditions \nCataracts \nGlaucoma \nNarrow angle glaucoma \nAcute glaucoma \nMacular degeneration \nSenile macular degeneration \nDiabetic lens osmosis \nIritis \nDiabetes - due to diabetic lens osmosis or diabetic retinopathy in diabetes and diabetes-related conditions: \nUndiagnosed diabetes \nPoorly controlled diabetes \nDKA \nHHNS \nPregnancy \nMigraine - causing visual effects prior to onset of the migraine. \nAnemia - see also types of anemia \nCertain kidney conditions \nCertain nerve conditions \n**Certain brain conditions \n**Stroke \n**Transient ischemic attack \n**Temporal arteritis \nSome possible causes of intermittent blurred vision or episodes of blurred vision including: \nDiabetic lens osmosis - blurred vision due to diabetes, DKA, HHNS, etc. \nGlaucoma \nAcute angle glaucoma - usually unilateral episodic blurring. \n**Multiple sclerosis \n**Transient ischemic attacks - i.e. multiple TIAs each causing blurring of vision. \nBlood circulation disorders \nCarotid insufficiency \nAmaurosis fugax \nCarotid embolism \nAtherosclerotic emboli \nVertebrobasilar insufficiency - causing episodic blurring or double vision. \nVisual hallucinations (see Vision distortion) \nAmphetamine intoxication - in high doses. \nCertain drugs \nDigitalis toxicity \nSee also causes of double vision or other vision symptoms \nNephroangiosclerosis \nHead injury \nConcussion \nRefractive error \nAccidental poisoning - e.g. accidental ingestion of antidepressant medications \nCertain medications"\n\nhttp://www.wrongdiagnosis.com/sym/blurred_vision.htm
1090360
Astigmatism\n\nWhat is astigmatism?\nAstigmatism occurs when the front surface of your eye (cornea) or the lens inside the eye is slightly irregular in shape, resulting in vision being blurred at all distances. Astigmatism is not a disease, but is actually a vision condition that is quite common.\n\nWhat causes astigmatism?\nWhen the front of your eye or the lens inside the eye is more oval than round, light does not focus properly on the back of your eye (retina). The causes of this irregular shape are unclear. In some cases, it may be hereditary or it may result from such factors as pressure of the eyelids on the cornea.\n\nHow common is astigmatism?\nMost people have some degree of astigmatism. However, only moderate to highly astigmatic eyes may need corrective lenses.\n\nWhat are signs/symptoms of astigmatism?\nPeople with severe astigmatism will usually have blurred or distorted vision. Those with mild astigmatism may experience headaches, eye strain, fatigue or blurred vision at certain distances.\n\nHow is astigmatism diagnosed?\nA comprehensive eye examination by your doctor of optometry will include tests for astigmatism.\n\nCan astigmatism by corrected?\nAlmost all levels of astigmatism can be optically corrected with properly prescribed and fitted eyeglasses or contact lenses.\n\nDoes astigmatism get progressively worse?\nAstigmatism may increase slowly. Regular optometric care can, however, help to insure that proper vision is maintained.\n\nHow will astigmatism affect my lifestyle?\nYou may have to adjust to wearing eyeglasses or contact lenses if you do not wear them now. Other than that, astigmatism probably will not significantly affect your lifestyle at all.\n\nFor more information, ask your optometrist.
337092
You should see an eye doctor to be sure. It could be stress, however, it could be something else. I'd check with a professional to be sure.
559526
Most of the time, those are brief after-images; it's a reflection of the processing of images by the retina.\n\nOn occasion, it can reflect retinal pathology--retinal detachment, occlusion of a blood vessel, etc--and it can be the prodrome of a migraine.\n\nIf it only occurs briefly and with closed eyes, it is generally nothing; the disease states usually will cause the little dots whether your eyes are open or closed.
735837
It sounds as if you may be experiencing floaters.  This is something that happens more frequently as people age.  It is actually gel or cells floating in the vitreous fluid (jelly like material within the eyeball) in your eye.  AS we age the vitrous fulid in our eyes thickens and this can lead to floaters.  You are actually seeing the shadows of the material off the retina. Floaters move with your eye as you move it because they are located within the eye itself.  Many times you can see floaters when you are looking at a light colored wall or background.  Floaters can be caused if you have experienced a blow to the head or can also be caused by a retinal detachment.  You should see an opthalmologist to rule this out.  If there is a sudden onset of the floaters it could be indicative of larger problems such as diabetic retinopathy, retinal hemmorhages or carotid artery disease.  If you are nearsighted, have had cataract or YAG surgery or experienced some inflammation or swelling within the eye, it could be a vitreous detachment.\nIt is impossible to diagnose this over the internet so you really should seek the attention of an opthalmologist for a true diagnosis of what you are experiencing.
1168556
most people call that a muscle spasm.  sometimes it could be a neurological problem, but I know a lot of people who have that at times.  Who knows why?  Maybe you were squinting too much and the muscles are tightening on their own now.
82009
It could be "Floaters" small pieces of dead skin that have worked their way into your field of vision, the eye sloughs off dead tissue like the rest of your body and sometimes it floats around in your vision, my mum has them and she just has to learn to live with them, best just to go to an optition for confirmation.
850405
me too! Its natural i guess cause my other friends say the same thing. But what is strange to me is that randomly everything in my sight goes blurry completely and I feel like Im going to faint. And what I mean by blurry, I mean seriously blurry like exactly how you become unconcious. And then quickly my vision returns.\nbut check with your doctor. Remember we only have one pair of eyes and cant replace them!
880795
Blockage from a blood clot is called a "partially occluded retinal vein" in the eye. Sudden symptom are the appearance of a gray foggy spot in the center of your vision, that sometimes fades, but never goes away. Some can be cured with an injection of a kind of steroid. Other causes are more serious. If an artery is affected you would go suddenly blind in that eye. In this case you need to get to the hospital NOW to avoid permanent damage. If you see something that isn't there, it could have to do with a detached retina. If you have any pain or other symptoms, you should seek medical help immediately. Good Luck