Strange circular shadow

[bluesquare]

Recently, I noticed that when I open my eyes upon waking from sleep, I see a black circle over my central vision that quickly disappears (as if dissolving). Both eyes display this behavior.

I can replicate the visual anomaly by closing my eyes again and opening them, but only shortly after I wake up. Any other time during the day, I am unable to observe this black circle. My central vision is fine otherwise -- no blurriness, no problems reading, no halos around lights, no trouble seeing in dim light, etc.

I am under 30 and had an eye examination about a month ago, and there were no signs of macular degeneration, glaucoma, or retinal detachment. Nevertheless, seeing a large, circular shadow in the center of your vision is a bit frightening, even if it is temporary. Have any doctors ever heard of this problem or know what might be causing it?

Thanks for your help.

[bluesquare]

I just found out that I can reproduce the visual anomaly by sitting in a dark room for several minutes, then turning the light back on and opening my eyes. Does this suggest that something is wrong with my eyes' ability to adapt to light?

My main concern is that I might be developing macular degeneration right after an eye examination. Do my symptoms at all indicate that might be happening?

Thanks for your thoughts on this.

[Doreen Fazio, M.D.]

If you sleep on your stomach, the symptom may result from pressure on one or both eyes.  The fact that it goes away so quickly is reassuring.  You are young for sleep apnea, but any condition that impairs oxygenation, including low blood pressure during sleep, could be a culprit.