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Visual Snow: What is this neurological disorder all about?

Nikki Alberta has a Master of Arts in Philosophy from the University of Alberta. She is a freelance article writer, novelist and blogger.


Visual Snow Introduction

Visual snow is a poorly understood neurological disorder that is just recently being studied as an entity of its own. People often describe it as a like a TV set without reception... that black and white static overlying across the visual field. A static that can be thin or thick, rapid moving or slow. It makes the world a little grainy and indistinct but shifting and moving at the same time. It is not unknown for people to describe heatwave effects, pulsing in the air, flickering in the visual field or other distortions within this static. Visual Snow is a visual condition often connected with persistent migraine auras but it can be seen it people who do not have migraines and in people who have migraines but experience no other aura phenomena. In fact, it does not behave like a migraine aura at all. Rather it seems like the visual filter hyperactive and not filtering out all that visual noise as it were so the individual perceives this constant moving static in their visual field. It is commonly worse in dim and dark environments but can be perceived at all times. This continuous visual disturbance consists of white and black dots, although some do have colours, in the entire visual field. A “female-to-male ratio of 1:2.2 was reported and 92% of patients had no response to medication. It appears to be a unique disease entity presenting clinically distinct from visual aura, and is often associated with other visual symptoms including floaters, palinopsia, halos, photophobia, and phosphenes. However, its onset seems to coincide with headache onset, and has a high prevalence among patients who have migraine without and with visual aura. The etiology is unknown.” (Primary headache disorders and neuroophthalmologic manifestations” Dove Press Journal Sept 13, 2012)

The Facts

Most neurologists believe the condition is a migrainous phenomenon in some way which is why most people with visual snow are diagnosed with persistent migraine aura. Yet visual snow does not act like a migraine aura nor does it typically respond to regular migraine preventative treatments. In fact, recently it has been stated by Dr. Chistoph Schankin “Visual snow is almost always associated with additional visual symptoms. It, therefore, represents a unique clinical syndrome – the visual snow syndrome," he said at the annual meeting of the American Headache Society. "It is distinct from visual aura in migraine; migraine with and without aura are common comorbidities, but we don’t actually know at the moment what is the pathological link between those two conditions.”

One of the unfortunate stigmas associated with visual snow is that it is caused by illicit drug use however according to research only a small percentage of people with the syndrome have ever used drugs.

The prevalence of other visual phenomena that occurs with visual snow is “showed that in addition to visual snow, nearly all patients reported other visual symptoms, such floaters (73%); persistent visual images (63%); difficulty seeing at night (58%); tiny objects moving on the blue sky (57%); sensitivity to light (54%); trails behind moving objects (48%); bright flashes (44%); and colored swirls, clouds, or waves when their eyes were closed (41%)” (Visual snow may be a distinct clinical entity)

While visual snow is found commonly among people with migraines the fact it occurs without migraines at all is fascinating in itself for research. Likewise, when it occurs in migraine patients without aura that is a clear indication something else is going on neurologically. "'I think it’s real.' Moreover, in her opinion, the presence of visual snow alone would be sufficient for diagnosis. 'I suspect it’s migrainous because most of these people have migraines. But it’s not aura. I don’t know really what it is. It’s incredibly frustrating because nothing works. You can try every antiepileptic known to mankind, and nothing works. So I agree that this is something we need to pay attention to and help these people.'" (Visual Snow May be Distinct) It would be interesting to have a study to compare people with just visual snow and people with visual snow with migraines without aura. Migraines have a peculiar way of firing up the brain even when the migraine is not present, as in such studies that show photophobia when a migraine is not present. It would be interesting to see if there is something about having migraines, of a certain frequency or duration of having them, that makes the brain more susceptible to developing visual snow. In this case, ignoring the visual aura phenomena that might happen to be affecting the same area of the brain in patients with migraine with aura. Or maybe comparing all three. Another interesting factor research much consider are the other symptoms. Those of halos and starbursts and things one might see with people with migraines occurring... is this a hyperactivity issue or similar to a migraine aura occurring in a similar fashion? Symptoms associated with the eyes themselves are even more puzzling but if the brain isn't filtering information properly it could have a connection to increased perception of visual phenomenon that is normal but just more frequent. Either way, something is making the system go haywire and by comparing those with just the visual snow to those with migraines and visual snow it might help see what the factors are that cause this to happen. New studies on just visual snow, however, show promise in revealing more insight in what is going on with this neurological disease.

It is a fascinating problem it presents trying to sort out what is causing it, what is going on and what treatments would actually be effective. For the people suffering it they often receive little care, more indifference from neurologists than anything or a lot of treatments that do a lot of nothing. In fact, the research indicates 92% had no response to medication. It can cause a great deal of frustration, confusion, and anxiety because the condition is a constant distorting perceptual phenomenon that can affect a great deal of a person's life.

The most recent research has located the region of the visual cortex responsible for visual snow: "the relationship to migraine and typical migraine aura was recently evaluated. Further, patients with visual snow differ from controls in respect of hypermetabolism in the supplementary visual cortex (lingual gyrus). This provides evidence that visual snow, despite being purely subjective in the individual patient, has a clear biological basis. The area of hypermetabolism overlaps with the functional correlates of photophobia in migraine supporting the close relationship of migraine and visual snow." Clearly, we now know it has a biological basis and is not 'in our heads'. It can be seen. It can be located. Again, we do have a correlation between migraines and visual snow that needs to be investigated further.

Nevertheless, it remains a rare disease that can greatly impact lives. For me, personally, I have never had any medication I have responded to. I also have persistent migraine auras and was initially told visual snow was part of that. Which is why I am intrigued by the research. My own experience was that the VS came far before the auras at the young age of 12 long before my first migraine with aura. Although I may have suffered with silent migraines before I had them with the 'bang'.

Visual Snow image


Old migraine case studies: Descriptions and treatments

These case studies come from persistent migraine aura research which up to present has been the majority of the case studies we have seen for treatment. Now that VS is being studies on its own, with another study due to come out Spring 2014, we should know more above the syndrome as well as potential treatments for it. Old treatments as we can see from these case studies follow along with migraine treatments to treat persistent migraine auras but is vastly less successful at treating the VS.

Nevertheless you might find them interesting to read as you will recognize the patients symptoms as VS. And you will see what their neurologists went about to treat it as well as whether the treatment was successful or not.

“Three-and-a-half years prior to evaluation, the patient developed a constant “rain-like” pattern in front of both eyes, at times appearing like a carpet background, often associated with the illusion of motion. Despite atenolol, the visual patterns intensified and converted to persistent “heat waves” with flickering lights. Although extremely uncomfortable, they did not interfere with visual function. She also reported five episodes of visual “black-out” and bright “daggers and spots” lasting 40 seconds each. He complained of 8 months of “snow” and “flickering” similar to what was “between TV channels.” Initially experienced only in dark illumination, eventually the visual phenomena became constant, without headaches. SPECT scan revealed bilateral parieto-occipital hypoperfusion. An EEG was not performed. Nifedipine was unhelpful, but sertraline reduced the visual phenomena by 50%.” (The last couple of sentences there apply to migraine auras and not VS just to be clear about that. This is a good example of someone with PMA characteristics and VS symptoms).

“she saw constant white and black dots, “snow,” and “TV static” over her entire visual field that worsened when she stared at a white background. Later, persistence of visual images (palinopsia) developed.”

“They commonly described diffuse small particles, such as TV static, snow, lines of ants, dots, and rain, that lasted for months to years. Some patients reported greater awareness of the visual phenomena when looking at the sky or at a light-colored wall. Complex phenomena such as palinopsia, micropsia, and formed hallucinations were exceptional. Some characterized these unformed visual hallucinations as bothersome, uncomfortable, or emotionally disabling, but not as interfering with visual function. Other patients were unconcerned by them. For the most part, medications such as tricyclic agents, calcium channel andbeta blockers, and analgesics were unhelpful. The patients’ ages varied from 9 to 67 years;”

Persistent positive visualphenomena in migraineG.T. Liu, MD; N.J. Schatz, MD; S.L. Galetta, MD; N.J. Volpe, F. Skobieranda, MD; and G.S. Kosmorsky, DO666 NEURO1,OGY 45 April 1995

“Over the next few years, the visual phenomenon was described as “snowy vision,” which was, present all the time and would worsen episodically, unassociated with pain. The subject described the visual phenomenon as like looking at a television with bad reception. It moved and swirled, and covered his entire visual field. When he looked at the sky or a white wall, the snowy effect was dark gray. He also saw constant “sparks,”“shooting stars,” and “floaters.”

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When the patient closed his eyes or looked at a dark surface, he saw the same effects, except that all of the visual phenomena were white, similar to looking at a sky full of moving and shooting stars.”495

“Since the age of 7, she rather constantly sees what she describes as television static that is getting worse and more noticeable. She sees tiny air molecules, also described as rain on a window, which are most noticeable if she is looking at the sky or a white background, present in both eyes and with the eyes closed. The symptoms can interfere with reading. “494

PMA”Medications reported as effective cyproheptadine, dihydroergotamine, divalproex sodium, (mono- and polytherapy) furosemide intravenous 20 mg once and verapamil, fusosemide intravenous 20 mg once, lamotrigine polytherapy, and nimodipine. In Dr. experience, low doses of divalproex sodium, and topiramate have been effective. In persistent visual aura was less intense on topiramate mg daily, and the palinopsia resolved. from starting treatment and complete response from several hours to 2 months and was typically weeks. Of the cases reviewed by Wang et reported headache improvement after treatment. the headache improved despite persistent symptoms, and in 2, the headache improved complete resolution of the visual symptoms. Most patients were reported as unresponsive numerous medications including aspirin, naproxen, carbamazepine, phenytoin, phenobarbital, divalproex sodium, lamotrigine, topiramate, diazepam, flunarizine, nimodipine, citicoline, verapamil, fluoxetine, sertraline, amitriptyline, nortriptyline, dothiepin, nifedipine, baclofen, propranolol, metoprolol, atenolol, sumatriptan, methylprednisolone,magnesium, acetazolamide, and pizotifen.

Migraine With Persistent Visual AuraHeadache 2012 American Headache Society (Headache 2012;52:494-501)

How would you say VS affects you

Visual snow in the News



Michi on January 27, 2016:

What can we do is the question everybody knows that it is bad,

Simon on June 16, 2015:

My child had developed VS soon after blinding dots from short use of an LED laptop which was setup too bright. First permanent experience of VS and hasn't gone since. Household lights were also replaced with LED's about 6 months prior, including close up study lights. After this happened all lights were again replaced with halogen and VS went calmer. Could be the same with modern flourescent lights which have a much higher blue light level, which is the damaging light, not the brightness itself, it overstimulates the visual brain area. Various research on LED's and eye damage and I predict VS symptoms will become widespread with LED's everywhere. Have you tried to look directly at an LED room light for 10 seconds and then close your eyes?

Also MTHFR C677, check yourself for this, because research shows a possible link between Migraine Aura (similar to VS) and C677T mutation.

Nikki Albert (author) from Canada on May 19, 2015:

I am not sure about that Micky. I know a lot of people with migraines are not pleased about it. And for the photophobia aspect of VS it will not be pleasant. But causally I don't know. There has been recent research on VS but I have not updated it on the page yet.

micky on May 19, 2015:

What about LED lights used as replacements for incandescents ones in the house and on computer monitors? I am sure these are involved in causing visual snow in some way.

believe on August 03, 2014:

I may be wrong but how I cope with it is I just assume we can see energy and deny it as a dissfunction but rather a gift

Nikki Albert (author) from Canada on March 09, 2014:

I can relate since I also rarely leave the house during the day unless I must. I hope that the new research that will be coming out soon will help target medication for us all. At this time it is a bit hit and miss with medications. The same sort of medications tried for migraine prevention are also tried for visual snow but with a far lower success rate. I have tried more than a few of them said to be beneficial and they had no impact at all. That is not to say they are not worth trying because some people do get a change in the snow quality or the other symptoms... like afterimages or something of that nature. You can definitely get a great deal of support and information from the Facebook group I mentioned in the resources there. There is a large number of members who have a varying amount of severity of symptoms. Doctors say it is harmless because they do not believe it is deteriorating the physical vision. However, it impacts our vision so it is hardly harmless to us. Unlike other people we cannot put on a pair of glasses and get clarity... we have to endure this constant motion distorting things. I do what I can do avoid sharp contrasts, patterns and bright lights. I use Flux on my computer screen to help with the lighting. I wear rose tinted glasses to also help with photophobia. And I use a lot of soft indirect lighting in my house for most things. I would recommend you join the Facebook group for support though. Maybe get some treatment ideas but at the very least have the company of others like us.

samkro on March 08, 2014:

Hello Nikki,

I found your blog while doing a search on visual snow. I suffer from very strong visual snow. I also suffer from blue field entoptic phenomenon and floaters. It's absolutely terrible. I have been to neurologists who checked the optic nerve, which was normal, and opthalmologists, who examined the eyes and found nothing except the floaters. Nobody could help me. I really don't know what to do anymore. It's becoming so bad that I can't leave the house anymore during the day. My eyes are also totally light sensitive. Do you have any ideas what might help or what kind of medical tests would make sense to find a possible cause of this?

Doctors always tell me it's harmless but I don't think it's harmless. I am 30 now and 10 years ago I didn't have any of this and it only gets worse. on March 06, 2014:

Yea im sorry but you know in web is so many misinformation. recent research shows that V-S is not a migraine but offen accompanied. Almost all people with V-S ho have hyperperfusion have migraine and migraine cause Hyperperfusion without infraction. No offensive rather scary for people who looking what going on

Nikki Albert (author) from Canada on March 03, 2014:

Those are direct quotes taken from papers referencing people with visual snow. Often those papers refer to VS as persistent migraine auras but do go into detail the symptoms and treatment that was offered. There has been only recently research devoted to VS in-itself. However, I wanted to include incidences and treatments shown in research past. I personally find the research interesting. Sorry you find those quotes so offensive. on March 03, 2014:

one more i read this study and have one conlusion you can't even wrote correct "A 30-year-old man had a 2-year history of classic migraine characterized by left homonymous streaks of light lasting 30 minutes followed by a pulsating headache associated with nausea and emesis. The episodes resolved with propranolol. His history was significant for marijuana use from ages 18 to 22, and his mother and m a t e r n a l grandmother h a d migraine headaches. He complained of 8 months of "snow" and "flickering" similar to what was "between TV channels." Initially experienced only in illumination, dark eventually the visual phenomena became constant, without headaches. SPECT scan revealed bilateral parieto-occipital hypoperfusion. An EEG was not performed. Nifedipine was unhelpful, but sertraline reduced the visual phenomena by 50%. " He has migraine and visual snow so that why he have hypoperfusion on March 03, 2014:

SPECT scan revealed bilateral parieto-occipital hypoperfusion but She also reported five episodes of visual “black-out” and bright “daggers and spots” lasting 40 seconds each. so she has migraine and migraine can cause hypoperfusion so how is this related to visual snow ? when you wrote something try to make it sense

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