Contact Lens Fitting?

Is there a relationship between the Sphere (-8.00, -10.00 etc), Base
Curve and/or Diameter of a contact lens in terms of its ability to
correct vision?

I ask because normally I wear B&L PureVisions with my right eye at Rx
-10.00, BC 8.6, Dia 13.8 and find this to be pretty good. But recently
had an emergency situation where I tried an Acuvue daily at Rx -10.00,
BC 8.5, Dia 14.2 and couldn't see very well at all. Just for the heck of
it I decided to try the same Acuvue in my left eye Rx of -8.00 (same BC,
Dia) in my right eye and found my vision much closer to the B&Ls.

In article <Xns95A3566DBDC13rljameshotmailcom@208.34.105.14 >,
Bob <(E-Mail Removed)> wrote:

> Is there a relationship between the Sphere (-8.00, -10.00 etc), Base
> Curve and/or Diameter of a contact lens in terms of its ability to
> correct vision?
>
> I ask because normally I wear B&L PureVisions with my right eye at Rx
> -10.00, BC 8.6, Dia 13.8 and find this to be pretty good. But recently
> had an emergency situation where I tried an Acuvue daily at Rx -10.00,
> BC 8.5, Dia 14.2 and couldn't see very well at all. Just for the heck of
> it I decided to try the same Acuvue in my left eye Rx of -8.00 (same BC,
> Dia) in my right eye and found my vision much closer to the B&Ls.

With soft contact lenses, base curve and diameter have little effect on
resultant optics, assuming the fit is correct. But the rigidity of the
material, optic zone diameter and surface stability certainly does,
especially when astigmatism (caused by cornea) is present.

The power number on the package is not the issue, What is important is
instead the resultant power number that provides the best vision.

--LB