Pages

nedeľa 29. decembra 2013

Seeing Spots: A Breakdown of Common Causes and Culprits

As an optometrist, I get a lot of questions.  People ask me about their eyes during their exam (of course), but also when I meet strangers on vacation, at the grocery store, or am just hanging out with friends.  Talking about eyes this much, some of the same questions inevitably get asked over and over. So here is one I know you all want answered:  what are those spots you see in your vision sometimes?

First, we need to break down the kind of spots you are seeing.  Remember, this is just a general guideline, so if you are seeing strange visual changes, you should see your doctor to be sure what you are seeing is normal and not a serious medical problem.
  • Floaters: Small dark or outlined shapes
    •  move when your eyes move
    •  most easily seen in bright or white backgrounds
    •  can be normal as the vitreous jelly that fills the eye breaks down during our teenage years
    • If you see a swarm of new ones at all once, see your doctor immediately as this could be a retinal tear!
    • Click here for more info
  • Phosphenes: Balls of light that can be seen even when the eyes are closed
    • Ever rub your eyes and seen spots afterwards?  These are phosphones.  Mechanical pressure can also cause the retinal photoreceptors inside the eye to trigger.  Since the retina cells only know how to communicate "light" they will respond the same to mechanical pressure as they do to incoming light!
    • Stand up to fast and see spots?  This is a type of phosphene resulting from orthostatic hypotension.  Basically with your quick change in positioning, blood flow to the eye was momentarily minimized, causing the eye to see these spots.  Remember, the retina can only say "light" so when the cells are getting less oxygen and nutrients than they need, they only can communicate that issue with a light signal. When blood flow returns to normal levels, the spots go away.  This can also occur if you are about to faint!
      Want to see some interesting art?  Check out this site for work depicting
      the artist's ocular migraine symptoms!
  • Visual Auras: Changing visual phenomenon
    •  Commonly described as waterfall motion, kaleidoscope changes, tunneling of vision, or a light that starts in the center and then expands out.  Medically this is termed scintillating scotomas or ocular migraine
    • Visual auras typically last around 15 minutes, but can last as long as 2 hours
    • Often followed by a migraine headache, but they don't have to be.  It is possible to just get an ocular migraine where only the visual symptoms occur
    • Vision will return 100% to normal within 2 hours.  If it does not, see your doctor immediately!
    • What's the cause?  Scientists believe a vascular spasm is the cause of these ocular migraines, and remember, when the eye gets blood flow disruption, it can only communicate by processing light.
Take home message:  your retinal cells are light communicators. They can't process pain (other parts of your eye can, but not your retinal cells!), so a retinal tear is as painless as a normal floater.  If you are seeing spots of lights, there may be a simple explanation that has nothing to do with your actual eye, just because the eye only can speak 1 language: light.  If you ever see flashing lights followed by vision loss, or a swarm of new floaters all at once, it is best to be seen by a doctor just in case it is a retinal detachment.  The only way to make sure your symptoms are normal is to have your eye dilated and checked by a professional.

Žiadne komentáre:

Zverejnenie komentára