My vision gets clearer when I press on eyelid

I have been told recently that I have an astigmatism in my left eye and my vision is now blurry in that eye. Can an astigmatism just show up after 40 years and blurry your vision in one eye. I am also going to get checked for corneal dystrophy in that eye. I noticed that if I press on my eyelid gently with my eyes open my vision gets clear, Any reason why this happens?

[Timothy D McGarity, M.D.]

Yes and yes to the first 2 questions. Vision clears with gentle pressure on eyelid: applies pressure to cornea and cornea has astigmatism; astigmatism: normal curve in one direction and steeper curve at opposite direction...your steeper curve is probably at 90 or 180 axis and pressure is making that axis more normal (temporary). Good luck!