So, when it happened a couple of days ago, I suddenly decided to see if I could read up about it (Prashanth Nuggehalli Srinivas' FB comment that "Everything is just a Google away" stuck in my mind!), and I found
is what it was.
However, in my case, migraine headaches don't always seem to follow the scotoma event (though this time, I did get a migraine yesterday, about 24 hours after the scotoma, which made me terribly nauseous and tired after the migraine attack was over) so I guess I seem to have
most of the time...
The scintillating scotoma is rather a spectacular display, I must say...
and in that, if you see the illustration of the spiral geometricscotoma, over the title, "Entry to art contest, Migraine Images, 1991" ...that's almost precisely what I see, unfurling and expanding across my vision.
Here's an almos precise description of what I experience, from the webpage above:
just had my first aura, without headache, yesterday. I had a breakfast of fresh pear and banana with yogurt at 9 a.m., then had a weight machine workout at 10 a.m. 15 minutes after the workout, I sat down at my computer and opened a document to read. I immediately noticed that I could not 'see' the word I was focusing on! The effect was similar to the local vision loss you get after having looked at a bright light. It’s not like the local area was 'black' – it was just 'missing'. After a couple of minutes, the small vision loss area began to drift to the left in my field of vision. I began experimenting with it by moving my finger horizontally and vertically through the vision loss area. I found that the blind spot remained when I covered either eye. At first, the blind spot moved left without getting any larger.
It was at this time that I witnessed the most bizarre phenomenon, which I have not read in the many personal accounts of aura on the Web. I opened a blank document on the computer and placed a letter on it. Then I adjusted my center of vision until the letter was in the blind spot. As soon as the letter was in the blind spot, the letter immediately began to reciprocate left and right in a very regular pattern both in time and space ('tick-tock-tick-tock-tick-tock') even though I was keeping my eyes and center of vision perfectly still. The letter moved a distance of about 1/2'' and back in about 1 second for each 'tick-tock'. It was as if my brain was trying to move the letter to a point where it could 'see' it, but couldn't decide on which way to move it!!
Yes, I was focusing on a point well to the right of the scotoma. The scotoma at that time was still very small, only about the size of the letter. The letter disappeared just momentarily, then it reappeared, alternating very regularly from left of the scotoma to right of the scotoma, never simultaneously on both left and right. But I was struck that this happened even when I very consciously kept my eyes, and center of vision perfectly still. It appeared to be a succession of two stationary images. It didn't 'slide' back and forth; it 'toggled' back and forth. I just saw the alternation of the two positions.
This phenomenon so interested me that I had not noticed something else going on further out in my field of vision. In the lower left quadrant, there was a vague sawtooth arc of scintillating images. I wouldn't say they were 'colorful', yet they had a quality that was almost colorful. At first, they were just sort of superimposed on the field of vision, without blinding me to what was behind them. But a minute or so after I noticed the sawtooth arc, it suddenly expanded into a large blind area consisting of a complete semicircle 'C' shape covering the entire left half of my field of view, as it also expanded all the way to the edge of my field of view. I think it may even have 'thickened', meaning the inner edge move closer to my center of vision. Before this, I had just been fascinated, but not at all worried. But when this major progression happened so quickly, it suddenly occurred to me that I may be having a stroke or brain aneurism, and I feared that I might be losing consciousness! Since no one else was at home, I grabbed the phone and dialed 911. I also became confused and had a little trouble actually dialing the phone and talking to the dispatcher. Later after reading other migraineur accounts, I believe my confusion was probably part of the aura.
When I hung up the phone, I stood up and began to walk around a little bit. It struck me that I was not the least bit dizzy or physically sick or anything. Then, the symptoms completely receded over a period of just a minute or so. By the time the ambulance arrived 15 minutes later, the symptoms were completely gone. I sheepishly walked out to greet the ambulance crew and reported my experience. They had no idea what had happened to me. They took my blood pressure, pulse and blood sugar, all of which were normal. After they left, I went back to my office and Googled 'temporary vision loss' and immediately got hundreds of hits on migraine aura. The many descriptions I have read on the Web left no doubt that this is what had happened to me.
I can't decide whether I can just leave this alone..and probably try for better sleep (which is a notorious problem for me) or whether I should go to a neurologist ...I've already checked out with an eye doctor, who's reassured me that it's nothing to do with my vision.)
However, the point I want to make is...if any of you have something unusual like this happening to you...don't, as I did, take it too casually (I thought it was something like the usual "threads" that one sees in the field of one's vision.)...Get it checked out. It may (like in my case) be nothing very serious...but if it is, you can get treated quickly. I'm glad this turned out to be not a big deal!