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Visual snow is a transitory or persisting visual symptom where people see snow or television-like static in parts or whole of their their visual fields. Other descriptions include visual static, dots, spots, grainy vision, pixellated vision, and more.
For a lot more information, visit our forum and connect with others who share the same symptoms as you: http://thosewithvisualsnow.yuku.com/forums/63
Update as of 10/24/2008:
From Jen Ambrose, founder, Eye on Vision Foundation
Hi 'Those with Visual Snow' Member,
Depending on how often you have visited the Visual Snow message board in the last few months, you may have seen that I've been working to get the Eye on Vision Foundation started. I knew that one day, we would need funds to help find a treatment for VS. Well, it looks like the day is here!!!! I have some great news! I have been in contact with a U.S. based neuro-opthamologist and I am setting up a fellowship for a doctor at USC to study VS. They will begin Phase I of the study, as soon as we can get the $15,000 together.
The doctors that I'm speaking with are willing to begin the project this month. I can't even tell you how excited I am about this.
Here is where I need your help. I can donate $4000 from the foundation, but we need to come up with the other $11,000 through donations. I'm not sure how familiar anyone is with medical research, but it is extremely expensive. $11,000 is only the start, and I really want to be upfront about that with all of you. We are in a rare circumstance with wanting medical research on a very rare condition. We aren't going to have the financial support of a cause such as diabetes or cancer. We are a small group and are going to need to propel a lot of this research ourselves.
Right now we have about 1100 registered members. That would mean that if each member donated $10 we would have our $11,000. The problem is that I know all 1100 members don't visit the boards. Some might not even be legitimate members, and people who just signed up out of curiosity. Cutting that number in half to 550 would mean each member could donate $20.
That is why I'm contacting the entire group today. If you can please try and donate $20 (more would be wonderful) this week or next we can get Phase I started right away. I am having a conference call with the doctors next week, and I will keep you updated. Unfortunately, we need to send them the $15,000 before the project begins, so the timing on this is crucial. Phase I will last from Oct/Nov 2008 - July 2009.
Phase I would be a case series review. The doctor would go through hundreds of patient charts to find cases of VS that they have seen at the University. Then make a systematic analysis of what they do and don't have in common.
Once a thorough study was complete of that small group it would move to peer-review publication. This will result in testable hypotheses and a wider awareness amongst physicians of the phenomenon.
The $15,000 that we need to raise would cover the cost of the doctors' time to review hundreds of charts.
Phase II would then start by the writing an IRB (institutional review board to do any clinical study, even observational), the analysis, etc. If the hypothesis involves blood flow, USC has the world's most sensitive measure of retinal blood flow (OCT doppler) which is so sensitive as to measure the difference between looking at black or white objects.
Donations can be made through credit card and PayPal and are tax deductible. Also, if you have a parent, sibling, relative or friend who is supportive of you, please ask them to make a donation. The $4000 that the foundation has raised so far has been about 90% from my own family and friends. People who are close to us are more than willing to help, and we could really use these funds right now.
v
http://www.EyeOnVision.org
v
Checks and money orders should be made out to:
v
Eye on Vision Foundation 14614 Josair Dr Orlando, FL 32826
The foundation does not have an office. I run it from home.
If we all pull together on this we can get this research project started right away!!!
Thank you so much for your support, Jen Ambrose
EyeOnVision@gmail.com http://www.EyeOnVision.org
Information about Persistent Migraine Aura/Visual Snow as written by Dr Klaus Podoll:
While the medical literature is silent, except for two papers by Liu et al. (1995) and Jäger et al. (2005), online there is active discussion about "visual snow", the most in-depth discussions taking place on the Yuku forum Visual snow or static founded in 2001 by George Farmer. This support group, administered by Ian Casey and privately funded by donations from its members, is regularly visited by a medical professional, Klaus Podoll MD, one of the editors of the Migraine Aura Foundation website, who is in charge for the assessment and evaluation of the responses to the Sofia Greene survey on persistent perception disorders which is distributed via this forum and other sites on the web.
According to the notion of hallucinatory form constants by Klüver (1942) and Siegel and Jarvik (1975), it can be conceived as a variety of visual hallucinations of random form dimension. As such, the phenomenon should not be confused with normal entoptic phenomena such as Haidinger's brush, which almost never have sufficient intensity to gain clinical significance as a source of suffering or functional impairment.
Visual snow, like all other forms of visual hallucinations, is non-specific as regards etiology (cause of illness). Therefore, each subject with a leading complaint of visual snow needs a full diagnostic work-up including ophthalmologic, neurological and psychiatric examinations as well as CAT or MRI scans of the brain.
Visual snow can occur in a variety of ophthalmologic disorders that can be diagnosed by the presence of additional clinical signs and symptoms.
Persisting visual snow can feature as a leading symptom of a migraine complication called persistent aura without infarction (International Headache Society, 2004), first described by Haas (1982) under the designation prolonged migraine aura status. It is important to keep in mind that there exist many clinical subforms of migraine where headache may be absent and where the migraine aura may not take the typical form of the zigzagged fortification spectrum, but manifests with a large variety of focal neurological symptoms including visual snow (Liu et al., 1995; Jäger et al., 2005), so that the condition is commonly underdiagnosed.
Another frequent cause of visual snow is Hallucinogen Persisting Perception Disorder (HPPD) following use of LSD, MDMA (ecstasy), psychedelic mushrooms or other hallucinogens. In HPPD, the symptom of visual snow has been described by Abraham (1983) as aeropsia (literally "seeing the air"). It is noteworthy that HPPD can occur after a single dose of a hallucinogen and with a considerable latency between last drug intake and onset of persistent perception disorder, so taking a thorough life-time drug history is mandatory in the diagnostic-work up of visual snow. There exists anecdotal evidence from single case observations that a variety of other illegal or prescribed drugs including cannabis, antibiotics, anti-depressants, neuroleptics, topiramate, digitalis, mefloquine, clomifene may cause visual snow or other symptoms of persisting perceptual disorder.
Another condition that may rarely produce visual snow is optic neuritis (inflammation of the optic nerve), often caused by multiple sclerosis (MS).
Moreover, a variety of illnesses (e.g. Lyme disease, auto-immune disease) or nocious events (e.g. prolonged use of a VDU, dehydration, over-acidification) have been blamed by sufferers in self-help internet forums as causes of persisting visual snow, but none of these claims have been supported by evidence-based medicine.
Some patients fail to find any apparent causative illness or event in their lives, instead saying the snow came out of nowhere or has been with them for their whole life. It has been suggested by Jäger et al. (2005) that such cases of "primary persistent visual disturbance (visual snow phenomenon)" may possibly represent a variant phenotype of persistent aura without infarction.
In addition to visual snow, patients suffering from persistent perception disorder frequently have other types of visual disturbances such as starbursts, increased afterimages, trails, palinopsia and many others (Podoll et al., 2006). Non-visual symptoms such as tinnitus or depersonalisation-derealisation are also frequently encountered. All of these additional symptoms have been described as manifestations of both migraine aura and HPPD, emphasizing the major importance of these two diagnoses for an explanation of the visual snow condition. Secondary psychiatric sequelae such as anxiety, panic attacks or depression may develop and necessitate appropriate treatment.
There currently is no established treatment for visual snow. In HPPD, clonazepam has been recommended as medication of first choice in patients seeking medical help (Lerner et al., 2001). Furthermore, drug abstinence is of major therapeutic importance in HPPD. In persistent aura without infarction, the evidence so far suggests that acetazolamide may be the premier drug for patients with the repetitive form of aura status (Haan et al., 2000) and that valproate (Rothrock, 1997), lamotrigine (Chen et al., 2001), or topiramate (Podoll et al., 2005) should be first choices for patients with the continuous form. When these oral drugs are ineffective, an intravenous injection or injections of furosemide should be tried (Rozen, 2002). However, with very little scientific research on the condition taking place, for the time being the effectiveness of such treatments remains based solely on anecdotal evidence. Beyond pharmacological approaches, appropriate counselling and cognitive behavioral interventions that focus on coping with the condition may be of huge importance.
References
Abraham HD. Visual phenomenology of the LSD flashback. Arch Gen Psychiatry 1983; 40: 884-889.
Chen WT, Fuh JL, Lu SR, Wang SJ. Persistent migrainous visual phenomena might be responsive to lamotrigine. Headache 2001; 41: 823-825.
Haan J, Sluis P, Sluis LH, Ferrari MD. Acetazolamide treatment for migraine aura status. Neurology 2000; 55: 1588-1589.
Haas DC. Prolonged migraine aura status. Ann Neurol 1982; 11: 197-199.
International Headache Society. The International Classification of Headache Disorders, 2nd edition. Cephalalgia 2004; 24 (suppl. 1): 1-160.
Jäger HR, Giffin NJ, Goadsby PJ. Diffusion- and perfusion-weighted MR imaging in persistent migrainous visual disturbances. Cephalalgia 2005; 25: 323-332.
Klüver H. Mechanisms of hallucinations. In: McNemar Q, Merrill MA (eds) Studies in personality. Contributed in honor of Lewis M. Terman. McGraw-Hill, New York-London 1942, 175-207.
Lerner AG, Kladman I, Kodesh A, Sigal M, Shufman E. LSD-induced Hallucinogen Persisting Perception Disorder treated with clonazepam: two case reports. Isr J Psychiatry Relat Sci 2001; 38: 133-136.
Liu GT, Schatz NJ, Galetta SL, Volpe NJ, Skobieranda F, Kosmorsky GS. Persistent positive visual phenomena in migraine. Neurology 1995; 45: 664-668.
Podoll K, Dahlem M, Greene S. Persistent migraine aura symptoms (e.g. visual snow). *Webpage from Migraine Aura Foundation website, 2006.
Podoll K, Dahlem M, Haas DC. Persistent migraine aura without infarction - a detailed description. *Webpage from Migraine Aura Foundation website, 2005.
Rothrock JF. Successful treatment of persistent migraine aura with divalproex sodium. Neurology 1997; 48: 261-262.
Rozen TD. Treatment of a prolonged migrainous aura with intravenous furosemide. Neurology 2000; 55: 732-733.
Siegel RK, Jarvik M. Drug-induced hallucinations in animals and man. In: Siegel R, West L (eds) Hallucinations: Behavior, experience, and theory. John Wiley and Sons, New York, NY 1975, 81-161.
Klaus Podoll MD, May 2008
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