This blog was first published in 2011 and had over 300 comments on my prior blog. Because it is such a popular blog post I am publishing it again.
There is nothing like experiencing a medical condition first-hand to really help a doctor understand it from the patient's point of view. After all these years, I had my first (and hopefully last) scintillating scotoma while sitting on the couch playing "words with friends" on my ipad and watching TV. A scotoma is a partial loss of vision in a normal visual field. Scintillate is flashing, sparkles. Put them together and you have moving, flashing sparkles with a blind spot in your eyes.
This visual aura was first described in the 19th century by a Dr. Hubert Airy who had migraine headaches. The visual sparks and flashes are in a zig-zag pattern and they can precede a migraine headache or occur without any pain. The scotoma affects both eyes and closing one or the other does not make it go away. Sometimes the term "ocular migraine" or "retinal migraine" are used to describe this phenomenon but these involve only one eye, not both. The terms are often used interchangeably but they are not the same.
The cause of these migraine auras are not understood. Only 20-30% of people with migraine headache experience them. The visual defect occurs not in the eyes, but in the visual cortex which is located in the back of the brain in the occipital lobe.
My scintillating scotoma lasted about 15 minutes and it took me awhile to figure out what it was. I went outside and gazed into the distance and it persisted. I closed one eye and then the other and it was still there. I never got a headache or any other symptoms. Then it just went away. There is no connection between this phenomenon and a stroke or permanent visual impairment, even though it can be quite scary for the patient who is experiencing it.
The next time a patient with classic migraine with aura comes in, I will have a better understanding of the prodrome before the headache. I hope I don't have to experience the entire headache. I could do without that.