Persistent Migraine Aura & Visual Snow (Part Three) (Last Edited: 2009 Nov 19)2008 October 11
This is the final part of a three part series. You can go back to part two from the links at the top and bottom of this page. Or you can jump to any part from the PMA & Visual Snow FAQs page link.
To finish this short series, I’ll relate my own experience. This list of symptoms may be of interest generally and to anyone with persistent aura or visual snow.
I’ve always or long had a few symptoms which I thought everyone had:
- Swirling pink-purple and green patterns in the dark. These repeat with change. I don’t always get them and they don’t usually last long.
- Spontaneous afterimages. These are rather like anyone would get if someone flashed a bright torch in their eyes at a distance. Except they pop up without any light source. They also take a while to disappear. The brightest and largest ones can last half an hour or more.
- A rushing, whistling, whining sound in my ears. This is called tinnitus. In my case I get several distinct but faint sounds all across my stereo field.
Because these hadn’t caused any problems I hadn’t bothered with them. Then just under three months ago I suddenly got a lot more symptoms. My GP diagnosed persistent aura, including visual snow. My specialist has confirmed the diagnosis:
- Something called Scheerer’s Phenomenon. This is where you see short-lived and fast-moving squiggles. These are normally seen against bright uniform fields like white walls or blue sky. You can see these normally without any pathology. Though not everyone does. They are how the brain interprets ‘gaps’ in the blood supply to the eyes caused by white blood cells. In my case it is constant in the right conditions.
- Visual snow itself. At first I confused this with Scheerer’s Phenomenon. Visual snow is like the static you get on an analogue TV in a poor reception area. It’s been described as like “seeing the air” and is also called aeropsia. In my case I see it in dim or dark conditions and it is pronounced most times. It is constant in the right conditions in my case. Though it did go away for a few minutes one night recently.
- Something I call sparklers. These are like exploding fireworks. In my case they take place at the centre of my vision. They usually happen when I go from looking at a bright scene to a darker one. Sometimes I see them while still in a bright scene. I get these most days. They last a second or two each time. They are usually green or orange in my case.
- Fasciculation(?) Localised involuntary twitching or nerves or muscles. These vary from day to day in frequency. Each event can last a second or two or for several minutes. The actual frequency of twitching can be a twitch every second or two to many times a second.
- Pinpoint flashes. These are hard to spot so I’m not sure how often I get them. They may be short lived spontaneous afterimages. The name I have given them describes them perfectly.
- A kind of scintillating scotoma I call “aurora”. These look a bit like the Northern or Southern Lights. But they are colourless. I get my aurora in my right field (side) of vision in darkness. It happens most times I go from lit to dark conditions. It lasts a few minutes before fading away. It is dimmer than the scintillating scotoma I get before a hemiplegic migraine attack. It is reactivated by light, even with my eyes closed.
- Another visual symptom I see in my centre of vision is something I call a “capillary”. This is because it resembles in many ways videos of red blood cells pumping through a capillary. Except that the ‘cells’ are white ringlets. They even pulse. I usually only see them in brightly lit conditions against a white field. Very rarely they end with a spontaneous afterimage. Worried about this, I asked my optometrist about them. After examining my eyes she said I had no damage. So it wasn’t a blood vessel bursting! Also there are no blood vessels in the centre of vision. These seem to happen more in my right eye.
- I also get a single stationary ringlet in the centre of my vision. Recently this has lasted several days. I see it when I blink. I now realise it is in my right eye and is a spontaneous afterimage that won’t go away. Though it has faded again. Usually I see this rarely.
Some rare visual symptoms I get are:
- Starbursts or rays. These look like short but very bright rays with patternation within them. They emerge from very bright usually point light sources such as the sun reflecting of a metal tap (faucet). They give the appearance of something like one of those floating seeds like from cotton. Except they shine. Very pretty!
- Halos. A misty veil of light surrounding a bright light source in dark conditions. Though the scene itself is not misted.
Any of these symptoms can increase when I get a hemiplegic migraine attack.
I can also spontaneously get the other symptoms of such an attack without the usually scintillating scotoma or headache. These usually last just a minute or two and are much milder. Most common are a short, mild burning sensation in one or other hand. This is usually associated with paresthesia (numbness or pins and needles) in a proper attack. Or I can get tingling in my top teeth. Sometimes I also get mild photophobia or hyperacusis: intolerance to light or sound. Finally I sometimes get short lived strobing or pulsating headaches. These usually last only a few seconds and can sometimes be severe.
Each person’s symptoms may vary. I have come across a support forum for people who have or think they have visual snow and are worried by it. Before writing a permanent page here, this is the link to that forum: http://thosewithvisualsnow.yuku.com/