4 ms·

There is Orthokeratology, which physically deforms the cornea via a contact lens, and lasts about a day or two. But it isn't ideal, and can have bad outcomes.

npongratz 6y ago
A day or two if you're lucky. If you happen to have corneas like mine, you'll get about 9 hours before suffering a fast decline: https://news.ycombinator.com/item?id=21546732 https://news.ycombinator.com/item?id=21546732 No lasting bad effects for me, at least. I'm still glad I tried it.
- skulk 6y ago
  Isn't there a period of time during this decline where you can't wear your normal corrective lenses because they are too strong? That sounds horrible.
  - npongratz 6y ago
    That's correct, at least in my experience. I could have worked around the every-afternoon decline by carrying a number of glasses in -1.00 to -6.00 and switching among them as needed, or by wearing the ortho-k lenses, which I could tolerate with my eyes closed while I slept, but would have been intolerable while performing any normal activities. Either way, that completely negated my goal of being able to live corrective lens-free during my waking hours. The other thing that really bugged me was the fact that these lenses could not correct my vision across my entire dilated pupil, and that issue also got worse as the day went on. That resulted in terrible halos around light sources in high contrast situations, such as at night when driving home from work.
rasz 6y ago
I remember learning about it while reading about someone doing this to pass 20/20 SFTI test (aka topgun).
Nicholas_C 6y ago
I wore ortho-k lenses from about 10 years old into my twenties. I switched to daily disposables as I think they are more convenient but when I was younger and playing more sports the ortho-k lenses were great. There is also some evidence that they can prevent eyesight from deteriorating.

npongratz 6y ago

A day or two if you're lucky. If you happen to have corneas like mine, you'll get about 9 hours before suffering a fast decline: https://news.ycombinator.com/item?id=21546732 https://news.ycombinator.com/item?id=21546732 No lasting bad effects for me, at least. I'm still glad I tried it.

skulk 6y ago
Isn't there a period of time during this decline where you can't wear your normal corrective lenses because they are too strong? That sounds horrible.
- npongratz 6y ago
  That's correct, at least in my experience. I could have worked around the every-afternoon decline by carrying a number of glasses in -1.00 to -6.00 and switching among them as needed, or by wearing the ortho-k lenses, which I could tolerate with my eyes closed while I slept, but would have been intolerable while performing any normal activities. Either way, that completely negated my goal of being able to live corrective lens-free during my waking hours. The other thing that really bugged me was the fact that these lenses could not correct my vision across my entire dilated pupil, and that issue also got worse as the day went on. That resulted in terrible halos around light sources in high contrast situations, such as at night when driving home from work.

rasz 6y ago

I remember learning about it while reading about someone doing this to pass 20/20 SFTI test (aka topgun).

Nicholas_C 6y ago

I wore ortho-k lenses from about 10 years old into my twenties. I switched to daily disposables as I think they are more convenient but when I was younger and playing more sports the ortho-k lenses were great. There is also some evidence that they can prevent eyesight from deteriorating.