Hello...this is due to dry eyes...when we keep reading for long...our blink rate decreases leading to dryness of cornea(anterior black round portion of eye). Measures to prevent this are...take breaks after every 1 hr of study....Blink..blink and blink a lot...do cold compresses....and use good quality lubricating eyedrop(refresh tears) 6 times/day.
Answered2016-02-15 15:42:55
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