Re: Had PRK 1 month ago (8mm pupils)

Hello fauzool, and sorry to hear about your situation. I had LASIK in one eye and PRK in the other four years ago. One month isn't a long time... I had massive and horrifying glare/halos/starbursts post-op, which improved significantly over three weeks, and slightly over four years, but not completely. Everyone is different.

I found several studies which say that, as long as the optical zone is ~6.0 mm or more, larger pupils did not have more night vision problems [u]after[/u] 3 to 6 months post-op. (Note that optical zone is smaller than treatment zone, which includes the transition or 'blend' zone.)

Which makes one wonder what [i]does[/i] cause night vision problems. A decentered ablation (not properly lined up) could do it. Dry eye, maybe.

I also found one small study to suggest that PRK tends to increase pupil size but that it improves with time. The average increase was 0.7 mm at 3 months and 0.2 mm at 21 months. For what it's worth, my PRK eye has a slightly larger pupil than my LASIK eye, but I don't have my records in front of me so can't say what it was before surgery.

Re: Had PRK 1 month ago (8mm pupils)

Yes - according to the FDA approval letters, the Visx Star S4 and Star S4 IR have an 8 mm treatment zone and 6 mm optical zone when used for nearsightedness, such as in your case. I don't know if they could be pushed beyond those sizes. For what it's worth, my own surgery used the Star S4 IR.

It seems deceptive for doctors to claim an 8 mm treatment zone when only 6 mm of that is optical zone. But again, supposedly, after 3 to 6 months, larger pupil sizes are not associated with more night vision problems as long as the optical zone is at least 6 mm.

One doctor claimed that the Star S4 doesn't always achieve 6 mm, but then, he works for a competing manufacturer (WaveLight).

For a long time, I got some starburst during the day with bright reflections, e.g. sunlight reflecting off metal. It pretty much went away eventually.

I'll PM you about the pupil size study.