I wouldn't say that hyperopes are more sensitive to chromatic aberration per
se, but that chromatic aberration is more noticeable with higher plus
lenses. As patients get older, the presbyopia on top of the hyperopia
results in much higher net reading power than myopes with presbyopia.

Personally, I don't consider a natural myope with presbopia to be a
hyperope, even if they only want SV reading glasses with a plus Rx.

I'd say that you're both right.  There are more hyperopes than myopes in
the world (assuming the narrow definition of hyperopia as anything over
0.00 spherical equivalent), but the vast majority of them don't need or
wear corrections. I do find more myopic corrections in my office than
hyperopic, but that is dependent on the demographics, as my average
patient is a young professional and his/her family. If I practiced in
some retirement village in New Mexico, I would imagine it would be more
plus than minus Rxs.

Anyway, I'm not sure about the idea of hyperopes being more sensitive to
chromatic abb. and can't off hand think of a reason why that would be.
I do have more trouble fitting hyperopes with progressives, but it seems
to me more a problem of lens design and small reading areas than chromatic.

w.stacy, o.d.

The clear majority of patients who go to opticians for glasses have myopia,
not hyperopia (or hypermetropia). That is one reason why poorly trained
opticians using a "one-solution fits all" often neglect the special problems
of hyperopia, particularly higher sensitively to chromatic aberration.

No.  I am an eye doctor, and I was thinking of hypermetropia.

A huge perecentage of my patients who get refracted have hypermetropia
(a bunch of these don't need glasses).

Remember, anyone who has a refraction with more plus than plano has
hypermetropia.

The incidence of hyperopia (like myopia) can vary depending on ethnic and
heredity background.

An American study published in Archives of Ophthalmology found that more
than 1 in 8 (12.8%) children between the ages of 5 and 17 have hyperopia.
(Kleinstein RN, Jones LA, Hullett S, Kwon S, Lee RJ, Friedman NE, Manny RE,
Mutti DO, Yu JA, Zadnik K; Collaborative Longitudinal Evaluation of
Ethnicity and Refractive Error Study Group. "Refractive Error and Ethnicity
in Children". Arch Ophthalmol. 2003 Aug;121(8):1141-7. PMID 1291269.)

A study of Jordanian adults aged 17 to 40 found only 1 in 20 (5.7%) were
hyperopic. (Mallen EA, Gammoh Y, Al-Bdour M, Sayegh FN. "Refractive error
and ocular biometry in Jordanian adults." Ophthalmic Physiol Opt. 2005
Jul;25(4):302-9. PMID 15953114)

A recent study involving first-year undergraduate students in the United
Kingdom found that 18.8% of British whites and 17.3% of British Asians were
hyperopic. (Logan NS, Davies LN, Mallen EA, Gilmartin B. "Ametropia and
ocular biometry in a U.K. university student population." Optom Vis Sci.
2005 Apr;82(4):261-6. PMID 15829853).

A recent Brazilian study, however, found that nearly 7 in 10 (71%) of the
students in one city were hyperopic. (Garcia CA, Orefice F, Nobre GF, Souza
Dde B, Rocha ML, Vianna RN. "[ Prevalence of refractive errors in students
in Northeastern Brazil. ]" Arq Bras Oftalmol. 2005 May-Jun;68(3):321-5. Epub
2005 Jul 26. PMID 16059562)

Unfortunately, many sales persons in optical shops who dispense lenses in
the US are poorly trained, and given that 87% of patients in the US are not
far-sighted, their special problems will likely be ignored with a
one-solution fits all recommendation.

Perhaps you were thinking of myopia (near-sightedness), which the most
common condition of young people who need eye correction, or presbyopia
(need for progressives or bi-focals that occurs with almost all adults
starting in their 40's).

[snip]

Really?

I find hypeopes to be a rather large percentage of the populaton.

Thank you for not calling me an idiot like Dr. Grant did.

Everyone seems to be calling the Rx of the OP low power, but with a +2.25
add on top of a +1.25 sphere, I would call it at least moderate.

My experience is that hyperopes (farsighted with a plus Rx for distance) are
more sensitive to chromatic aberration. And since hyperopes are small
percentage of the population, their special problems are often mistreated by
lens dispensers. Since the OP specifically claimed that he is "very
sensitive" to chromatic aberration (perhaps because he is a hyperope?) ,
then it might be of more concern than normal.

True, but you'll probably not notice that small difference.  My reason
for (rarely, as in this "choice") choosing the polycarb is the greater
production/availability of polycarb progressives over 1.67 means that
you might get better optics otherwise.  By that I mean the manufacturers
may have put more effort into the designs of the polycarbs, since it is
by far more commonly used, esp. in the lower powers as in this case.
But that's just a hunch based on experience.

w.stacy, o.d.

However, the abbe value for 1.67 is slightly higher than polycarb, which
means 1.67 should have less chromatic aberration.

Locked out of free choice by someone?  Anyway if I had to choose between
the lesser of 2 evil lenses, I'd go with the poly in your Rx, because
it's pretty low power so chromatic abb will not be a large factor...

w.stacy, o.d.

Yea, I think that would have been my first choice... If it was an option.
It's not. The choice is between polycarb or 1.67

-Quick
 Not sure if I missed it, but someone should recommend a Trivex ECP by hoya.  It's a great, thin, strong, light lens with little aberration.  I wear them myself and love them.

 w.stacy, o.d.

 Quick wrote:

CatmanX wrote:
 Buddy, you are an idiot.

Physio 360m is a much better lens. Pay the $20.00 and be
happy it was well invested.

Airwear is fine for lower scripts. Chromatic aberration is
inconsequential at these scripts. The benefit of 1.67 is
it is virtually unbreakable - more so than airwear.
Airwear is cheaper and great for rimless fits.

Quick, stick with the physio 360, multicoated and choose
the material you are happy with.\
   
I've decided on the Physio 360 (over the Physio).
I have decided on the Air Titanium drill mount frames.
I don't know what "Airware" is.... Is that another term for
polycarb?

I'm not sure what lens material will make me happiest :)
The viable alternatives are polycarb and 1.67

I have no qualms about the extra money if there
is any advantage at all to the 1.67 over polycarb
given my Rx.

For all I know polycarb might be better than
the 1.67 given my Rx.

I have no idea if the materials effect the transitions
performance differently.

At the moment it sounds like I'm going with the 1.67

thanks,
-Quick

 

Not sure if I missed it, but someone should recommend a Trivex ECP by
hoya.  It's a great, thin, strong, light lens with little aberration.  I
wear them myself and love them.

w.stacy, o.d.

I've decided on the Physio 360 (over the Physio).
I have decided on the Air Titanium drill mount frames.
I don't know what "Airware" is.... Is that another term for
polycarb?

I'm not sure what lens material will make me happiest :)
The viable alternatives are polycarb and 1.67

I have no qualms about the extra money if there
is any advantage at all to the 1.67 over polycarb
given my Rx.

For all I know polycarb might be better than
the 1.67 given my Rx.

I have no idea if the materials effect the transitions
performance differently.

At the moment it sounds like I'm going with the 1.67

thanks,
-Quick

Buddy, you are an idiot.

Physio 360m is a much better lens. Pay the $20.00 and be happy it was
well invested.

Airwear is fine for lower scripts. Chromatic aberration is
inconsequential at these scripts. The benefit of 1.67 is it is
virtually unbreakable - more so than airwear. Airwear is cheaper and
great for rimless fits.

Quick, stick with the physio 360, multicoated and choose the material
you are happy with.\

dr grant

"Quick" <quick7135-news@NOSPAMyahoo.com> wrote in message news:q5Omg.49044

You are correct that 1.60 is not available for Varilux Physio 360. Therefore
I would strongly consider the Varilux Panamic which is available in 1.60.

I don't think that's an option. I think the Physio 360 is only
offered in polycarb, 1.67, and they just added CR-30 which
has been recommended against due to the drill mounts.

thanks,
-Quick

Polycarb has the worst chromatic aberration of any commercially available
lens material (measured by abbe value) regardless of index. Avoid it like
the plague.

Except for polycarb, the higher the index, the worse the chromatic
aberration. 1.67 is overkill for you. I would go with 1.60 at the most.

Ok, Doc is really advising against CR-30 and recommends
polycarb, or as an alternative 1.67, 'cause I'm getting drill
mounts. Air Titanium rimless.

O.D. +1.25 sph add +2.25
O.S. +0.75 -0.25 add +2.25

Physio 360
Crizal Alize with Clear Guard (gold)
Transitions (grey)

Yea, I know, I don't need the 360... it's only $20 more.
I don't play Jai Lai

So...
I don't expect the difference in thinness to be measurable.
I don't expect the difference in weight to be noticeable.

Is there any possibility I could see any material caused
abberations with either (I'm very sensitive to that sort of
thing)?
Would there be any difference with the transitions
performance?

Price difference is about 10% of total so not a factor
if there is any advantage to the 1.67

-Quick