Eyesight degeneration due to short sleep/computer

Hi.
If my eyesight is 70-80%, and I sit near a computer for 9 hours straight near an old monitor, then sleep for 4 to 5 hours, how much could my eyesight be worse the next day? Could it get down to 30-40%?

[Ray T Oyakawa, MD]

Prolonged computer use can induce myopia.  It also depends on the refraction in your eye.  If you are slightly nearsighted and do not wear glasses it is less of a problem.  Also, computer glasses will help.

Dr. O.

[questioneer434]

Thank you for your answer.

However I meant a short term effect. Let me give you a situation:

I have to write an essay and I am working on it for 9 hours straight without wearing any glasses. I'm writing it with my poor-quality monitor where the text is a bit blurry. After I'm finished, I go to bed and sleep for 4-5 hours.

In this situation, could my eyesight go down to 30-40% from 70-80%?

[questioneer434]

Sorry, I forgot to mention - I mean that it would be like that just for one day, until I would get a good night sleep and my eyes would rest.