Why does my vision blank out when I'm relaxed?

April 26, 2013 11:29 AM

Sometimes when I'm relaxed, for instance sitting at my computer, I start to lose vision in my left eye. It usually takes the form of a dark "C" or donut around my central vision (e.g. I can see through it to a single word but it covers up most of the web page). If I blink or even move my eye in the slightest, it goes away, returning in a few seconds if I am still relaxed.

This has been happening for at least a year or more. I went to the ophthalmologist recently, he looked at my retina etc. and diagnosed it as a floater or posterior vitreous detachment. I've had floaters all my life (the squiggly stringy kind) but never one that acts quite like this.

Wondering if this is typical for someone with a PVD (I've read about Weiss ring floaters but having trouble finding an exact description of picture) or if I should be worried about something else related to blood flow issues in my eye.

posted by RobotVoodooPower to Health & Fitness (9 answers total)

Anecdata: I Had this exact thing occur to me once, spontaneously, during a meeting. It dissipated after about 20 minutes. I described it to a colleague and he said he got symptoms like that connected to his migraine episodes. Not all migraines involve headaches and nausea, apparently.
posted by BigLankyBastard at 11:36 AM on April 26, 2013

I've started getting those, will report it to my COVD eye guy. Maybe get a second opinion with a more diagnostic-styled exam with someone who is part of covd.org?
posted by tilde at 11:58 AM on April 26, 2013

Basic question: are you breathing when you're that relaxed? Sometimes when I'm really relaxed I forget to breath or I hold my breath. Lack of oxygen could make you start to black out. It seems ridiculous, but how much attention do most of us really pay to our breath?
posted by postel's law at 12:06 PM on April 26, 2013

http://en.wikipedia.org/wiki/Scintillating_scotoma
Scintillating scotoma is the most common visual aura preceding migraine and was first described by 19th century physician Hubert Airy (1838–1903). It is often confused with ocular migraine which originates in the eyeball or socket.
Scintiallting scotoma might not be what is happening to you. Would a visit to an ophthalmologist be in your future?
posted by Cranberry at 12:13 PM on April 26, 2013 [1 favorite]

I have had symptoms on and off like that for years, after a lot of doctors the general consensus is optic migraines, in my case bought about by inter cranial hypertension or pressure increases in my brain pressing on my optic nerves, but they have recently started being triggered by flickering lights as well. I am one of the lucky ones that doesn't get the headaches just the visual field disturbances. I'd maybe look into seeing a specialist in PVD if you have concerns and get all your questions answered.
posted by wwax at 12:38 PM on April 26, 2013

I'm not an eye doctor or anyone with any kind of expertise whatsoever, but:
Does it happen when you're relaxed, or does it happen when your eyes aren't moving much? If part of your retina isn't sending signals to the brain, it might appear as a dark spot in part of your field of vision if you try to keep your eyes still for a while, but as soon as you move your eyes, that part of your field of vision now falls on a different spot on your retina-- one that is working properly-- and your brain fills in the gap. It's the same sort of thing that happens normally with people's blind spots.
posted by grahamsletter at 2:23 PM on April 26, 2013 [1 favorite]

I've had amblyopia most of my life. My right eye has much worse vision than my left eye. My brain compensates by relying primarily on my left eye for detail, and my right eye only for peripheral vision, depth perception, and motion. If I stare at one thing for a while, my bad eye starts to black out just as you described. This even happens if I've covered my good eye.
posted by WasabiFlux at 8:03 PM on April 26, 2013

Response by poster: Thanks for the replies, all. I have been to an ophthalmologist but I think his diagnosis was more "your retina's fine, at least" rather than positively identifying any cause. I didn't know about COVD, thanks. I think it's related to not moving my eye, but only in one eye. I do hold my breath but not enough to black out :)
posted by RobotVoodooPower at 6:23 AM on April 27, 2013

Go see a retina specialist.
I was given a similar diagnosis by 3 regular ophthalmologists. I saw a retina specialist and he found tiny holes (like retinal tears) in both eyes. I had the eyes zapped with a laser.

I have floaters. I have had aura-only migraines for years. They are different conditions. While I can make the floaters move by moving my eyes, shifting my eyes about does nothing for the aura.

So I would suggest you see a retina specialist just to get the problem thoroughly checked out.
Mefimail me if you wish.
posted by PickeringPete at 6:42 AM on April 27, 2013