| I normally wear glasses for distance vision. I hadn't realised that my visin had gradually become worse.
In hospital once they had got my BS down I could look out of the window and see for ever.It was a fantasic, though slightly weird feeling. On the otherhand I couldn't bear to watch the TV in my room because I was far too close to it. My eyesight went back to 'normal' very quickly (actually slightly better than my most recent prescription)
Apparently high BS causes the fluid levels in the lens to change (because of osmotic pressure) The change in the fluid level changes the refractive index of the lens causing (usually) increased myopia. Rapid correction causes the levels to change again leading to farsightedness. Eventually, if BS stabilises everything settles down and the vision returns to what it should have been without the high BS. (source Gretchen Becker) | 
