Ocular Aura, Asymptomatic Optic Neuritis, and their relation to Multiple Sclerosis
Last month, a strange thing happened. I was sitting at the computer engrossed in my moderating/writing stuff, when suddenly my vision went wonky, sort of the way it does when you glance directly at the sun. I could still see the computer screen with my left eye, but when I closed that eye, the vision in my right eye was dark except for a luminous crescent hanging suspended just right of center. Oh my God, I thought, I’ve gone half moon-blind.
(In case you thought you were going daft, half moon-blind is not a thing. I just made it up to suit the situation. Now back to the story.)
Almost immediately the vision was restored in my right eye, but the crescent had turned prism-like with red and green rays shooting out from it. As I continued to watch this lavish spectacle, the crescent grew translucent and white with sharply defined angles and intricate designs, like a snowflake or a filigreed piece of jewelry. I could see right through it to the computer screen, where I began typing into the search box a description of everything I was observing. A term popped up in Wikipedia with a whole article explaining it.
The phenomenon I described is called a Scintillating Scotoma. Apparently I had a classic case of it, because the article described it almost exactly as I was experiencing it. The suspended object, flashing colored lights and temporary blindness are symptoms called a visual aura, which can precede a migraine headache. I did not get the headache, however. It is also known as an ocular migraine or silent migraine, yet those have some different causes.1
Since I’m a stickler for thoroughness, I did call my neurologist’s office and report my symptoms in detail to the nurse; my doc was out of the country. I tried to be a good patient and not diagnose myself, so I left out the part about researching my symptoms and finding the name of the syndrome—for about 30 seconds. (I’m hopeless, the girl just can’t help being a know-it-all.) When my doc did check in, she said it did sound like an ocular migraine and was not MS-related, and that we didn’t need to do anything about it. I asked whether I should see an ophthalmologist, and she said it wouldn’t hurt to see one.
For a long time I’ve neglected seeing an ophthalmologist; in fact, I don’t think I’d ever been to one. Having had MS for 16 years, I was overdue, so I made an appointment for a baseline exam. I did report the symptoms and added that I’d had a history of migraine headaches starting at age ten but had never had the aura. Ironically, I told him, now I’ve had the aura without the headache! The ophthalmologist nodded knowingly at this information and said that it is so very common; after decades of migraines without aura, the painful headaches can fade while auras appear without an accompanying headache. I’ll take the aura over a headache any day!
And here is when a second strange thing caught me totally off guard. The ophthalmologist performed some additional tests and confirmed that scarring was present in my left optic nerve. It is evidence that I had optic neuritis at some point, probably asymptomatic since I don’t recall having had vision problems. The good news was that despite the scarring, there was no inflammation and no evidence of vision damage in either eye. I got a clean bill of eye health, which was a great relief after being told that I’d experienced optic neuritis without knowing it!
I learned some interesting new things from these two events:
- Our headache patterns can change over time,
- Ocular auras can be harmless progressions in a lifelong history of migraines, and
- Optic neuritis isn’t necessarily symptomatic.
These epiphanies reminded me that we should always consult our specialists about our symptoms whether or not we’ve researched them first. Tests are proof of the pudding, you might say. A visual aura might be harmless, but it also might be the smoking gun evidence that you’ve had a stroke or a retinal or vitreous detachment. A doctor’s exam is a vital part of diagnosing these symptoms. Blowing it off could have serious consequences.
Are migraines, silent or full-blown, connected to Multiple Sclerosis and MS-related optic neuritis? As far as I’ve been told, having a history of migraines can be an early symptom of MS. Mine started at age ten. When I told my first neuro that, he nodded as though he’d heard it a thousand times before. My current neuro maintains that migraines are vascular in nature, and the aura I experienced falls into that category as well.
Have you experienced migraine headaches with or without an aura, or silent migraines with crescent shapes like the one I mentioned above? What has your neurologist told you about it in relation to your MS?