Several different eye problems can cause you to see bright spots or what appear to be light flashes. Some of these can be serious, so I would call your eye doctor to check it out. Some of these conditions can lead to vision loss, so I would go ahead and call today. You need an eye doctor to examine your eyes as I am not able to tell what might be going on without an examination.
Bright spots that come and go could possibly be caused by pressure on your optical nerve. I had this a couple times a long time ago. Some say it could also preceed a migraine. I didn't have the migraine, but I was under a great deal of stress at the time. it hasn't reoccurred since then, but it really bothered me. My eye doctor and physician told me the veins around the optical nerve can enlarge a little and move into the optical nerve, causing the vision problem.
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