My vision was nearsighted about -8 correction with about 2 diopters of astigmatism, cylinder correction.With cataract surgery, you get to decide what kind of correction you'd like to have after the surgery. You get to choose, that is, within the skill level of the institution that measures you up and does the surgery. Needless to say, they don't inform you the standard deviation of their results.
I chose the standard answer. I'd like zero correction, drive a car without glasses. Retrospectively, I think I'd like to have retained the amount of nearsightedness that would be suitable for a guy who spends a lot of time on a computer, reads in bed, etc.
Here's what happened: I paid $500 extra for "Toric" lenses with cylinder correction, i.e. astigmatism. After the operation my spherical correction was about perfect. My cylinder correction though, went only half way to normal. My average cylinder was 2.5. Now it is 1.25. OK, I can pass the driver's test without glasses. BUT. But I prefer to drive with glasses because that remaining cylinder correction is quite noticeable. I definitely see distance better with glasses. When you are driving, you are often struggling to see small signs far away so excellent vision is important then. On the other hand, when you are reading, you are not stressing for perfect focus. You can easily move your book or your head a few inches. Had I asked to be corrected for something like 1/2 meter = 2 diopters, I'd be on the computer now without glasses. Heck, most my life I'd be without glasses.
Right now my eyes are 22" from the computer screen. That would be 1/(22x2.54/100) = 1.8 diopters. Do not follow my advice if you spend most of your time watching television! If you are a TV lover, do as I did, not as I say.
My other personal advice is to buy your glasses on line. Insist the bifocal line to be half way up the lens. Ordinary glasses are under $10, bifocals about $25, so buy lots of different glasses to experiment with. Still haven't made up your mind about what correction you want after cataract surgery? Glasses are so cheap, you can experiment in advance by trying out various corrections.
At my final consultation I gave a copy of this document to my eye surgeon, Jason W. Much. His reply: "I'll scan it and put it in your file."