I saw this post in All my Circles by Devernder ji.
Glaucoma and I
Glaucoma is a silent eye disease. The victim does not realize the effect of glaucoma, even until, the loss of vision is almost 100% in affected eye. The onset of glaucoma can be checked by simple test at home itself.
One needs to lie down straight and focus vertically up on ceiling. Close one eye at a time and view the ceiling, without moving the eyeballs or changing the point of focus. The area of vision with each eye should be equal. If the areas of vision are different, then the eye with lesser vision area is affected. Normally the right eye is affected first and, to best of my knowledge, both eyes are not affected simultaneously.
Once the reduction in view area is noticed, immediately contact eye specialist.
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