Prescriptions higher for Lasek?

[Conor]

Wow there's a lot of spam in here! Still, if anyone see this message
in between all the noise I'd be interested in your opinion:

My glasses prescription is -6 sphere, with -0.50 of cylinder. My
current glasses are -5.75 and I'm aware that I can't see license
plates at 1000 metres, but don't care very much! The world is ugly
enough without seeing more of it 8-)

Anyhow. I went for a Lasek consult in 2006, which I walked away from
because there was no Schirmer tear test and no test of my dark adapted
pupils. And I didn't like him. He did tell me my corneas are
borderline for lasik though (500 microns). He then just took the
numbers from the autophoropter (or the pretty colour topography maybe)
and said "we can fit you in next week". So no thanks. His numbers were
-7 with 0.50 of cylinder or thereabouts.

Repeated the lasek consult with another place in Dec 2009. They did a
bunch of tests, including a refraction. The numbers were -6.5 with
-0.50 of cylinder (at least that's consistent). The autophoropter gave
a -6.75 which he said is just a estimate really.

So, the thing is: Why the inconsistency? -6, -6.5, -7? This is all a
bit vague.

I tried a -6.5 contact lens that the surgeon gave me as part of a
monovision trial. It sucks; it's way too strong. If I ended up at that
prescription I'd lose near and intermediate vision. No way. Do
surgeons have a target - must get 20/20 far vision and to hell with
near/intermediate. Hey, you can have monovision or wear reading
glasses. It just doesn't seem reasonable to me. Especially as my
father was about -2 when he was young and is about -1 in his 70s. Can
drive and read without glasses. I get the impression you can gain 0.5
to 0.75 diopters with age...

Oh and does anyone know if chemically induced pupil dilation gives a
pupil diameter equivalent to that you'd expect from a dark-adapted
maximum pupil diameter? Can't find anything on Google.

Thanks all,

Conor.

[serebel]

Post by Conor
Wow there's a lot of spam in here! Still, if anyone see this message

Used to be fun here. Now, just tumbleweeds.

Post by Conor
My glasses prescription is -6 sphere, with -0.50 of cylinder. My
current glasses are -5.75 and I'm aware that I can't see license
plates at 1000 metres, but don't care very much! The world is ugly
enough without seeing more of it 8-)
Anyhow. I went for a Lasek consult in 2006, which I walked away from
because there was no Schirmer tear test and no test of my dark adapted
pupils. And I didn't like him. He did tell me my corneas are
borderline for lasik though (500 microns). He then just took the
numbers from the autophoropter (or the pretty colour topography maybe)
and said "we can fit you in next week". So no thanks. His numbers were
-7 with 0.50 of cylinder or thereabouts.
Repeated the lasek consult with another place in Dec 2009. They did a
bunch of tests, including a refraction. The numbers were -6.5 with
-0.50 of cylinder (at least that's consistent). The autophoropter gave
a -6.75 which he said is just a estimate really.
So, the thing is: Why the inconsistency? -6, -6.5, -7? This is all a
bit vague.

Go to ten different optometrists and you'll get ten different
script numbers (although close to each other).

Post by Conor
I tried a -6.5 contact lens that the surgeon gave me as part of a
monovision trial. It sucks; it's way too strong. If I ended up at that
prescription I'd lose near and intermediate vision. No way. Do
surgeons have a target - must get 20/20 far vision and to hell with
near/intermediate. Hey, you can have monovision or wear reading
glasses. It just doesn't seem reasonable to me. Especially as my
father was about -2 when he was young and is about -1 in his 70s. Can
drive and read without glasses. I get the impression you can gain 0.5
to 0.75 diopters with age...

Monovision is not for everyone,as it takes time to get used to it.

Don't compare your eyesight with your father, genetics do not quite
work that way.

Post by Conor
Oh and does anyone know if chemically induced pupil dilation gives a
pupil diameter equivalent to that you'd expect from a dark-adapted
maximum pupil diameter? Can't find anything on Google.

The chemical dilation opens the pupil wider than the dark.






Good luck, keep asking questions and you'll do just fine.

[Conor]

Post by Conor
Wow there's a lot of spam in here! Still, if anyone see this message

      Used to be fun here.   Now, just tumbleweeds.

I remember the early 90s, before spam was invented. Sigh. Oh well...

Post by Conor
So, the thing is: Why the inconsistency? -6, -6.5, -7? This is all a
bit vague.

      Go to ten different optometrists and you'll get ten different
script numbers (although close to each other).

Yes, there're all -6 or so depending on how far the optometrist thinks
I'd like to see. When I mention most of my work is close up the script
reduces a little. Never had someone say more than 6.25. -7 is a lot
more and loses me my close up vision.

Monovision is not for everyone,as it takes time to get used to it.

I'm second guessing the guy but I believe a -6.5 contact lens is about
a -7 sphere in glasses (at least it is for me as *I* perceive it. My
-5.50 contacts are a little stronger than my -5.75 glasses. Your
milage may vary). So he might have done it deliberately to see how I
might be in 20 years time. Maybe I should go and ask him! He gave me a
-6 contact to try as well which I will next week.

Don't compare your eyesight with your father, genetics do not quite
work that way.

Well no. But his short sightedness worked out well for him in the long
term. His distance vision got a bit better as he got older and his
residual myopia stood to him for reading etc. I know of at least one
person, an opthamologist, who deliberately got her lasik done so she
ended up at -0.5 in each eye for precisely this reason. I'd be
inclined to want to be -6 corrected, not -6.5 too. I think opticians
are too insistant on complete plano - in my opinion if my child was
-0.50 or -0.75 glasses wouldn't be necessary and I simply wouldn't
stand for an optician prescribing them (except for school maybe).

 The chemical dilation opens the pupil wider than the dark.

Ah. That's good to know. I believe mine was between 6.5 and 7mm but
I'm not sure. If it was 8mm I'd probably think rather more carefully
about what that laser is doing!

Thanks for the info.