听力原文：M: What trouble are you having with your eyes? W: Well, I'm a bit tired and you know I do a lot of reading because of my work and besides our room is in the basement in the Department of English and we always work with electric light. I'm very tired I think. M: Does the print get blurred as you're reading at all? W: Sometimes, yes, especially at night. M: You manage in the distance all right? W: Yes. And also you see, doctor, I drive so erm you know this check-up is absolutely necessary. M: What I want you to do is to look into the distance. Right! Look through me. W: Through you? M: Right you are. I'm going to shine a light in your eye don't worry about that. W: Ok. M: Your eyes, they are completely healthy. You just need slightly different glasses. It'll make you see a little bit clearer and a little stronger, but your eyes are basically normal. W: Doctor, erm what do you think about contact lenses? Do you think it's worthwhile for me getting some or not? M: Not in your case. If your left eye was as bad as your right eye, I would say yes, but at the moment you see nicely with your left eye nakedly. Which of the following is NOT among the reasons leading to the woman's eye problem?