How long does the black cloud image persists?
Have you seen an ophthalmologist yet?
Does it happen with both the eyes?
The black cloud image persists, I think, until I get out of bed. I could wake up in the middle of the night with it and still be there in the morning when I wake up and I would say it goes away shortly after I wake. Well, both my eyes are open when it happens. And no, I have not been to an opthamologist EVER.
These black cloud images may be due to posterior vitreous detachment which is a normal ageing change. The vitreous gel in the back part of the eye liquifies and separates from the retina to form a clump which may be visible to you as a black cloud. Another possibilitiy could be the lack of blood supply to the brain(due to gravity) on getting up suddenly from the bed. This is likely if you see the cloud after getting up from the bed. However, if you are seeing the cloud in the bed itself(as you have stated), this is unlikely. Other causes for cloudy vision include retinal detachment or vitreous hemorrhage. The cloudy vision in such cases is more likely to persist and not go away in a few minutes after waking up. To confirm the cause you need to see an ophthalmologist for a dilated eye examination. Thanks and best wishes.
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