Let's Begin the New Year with some CONTROVERSY!

[Barry Santini]

Yep, I think this board's been too quiet of late. So, from a discussion that started on FB, I ask the following in the form of a poll?

Vote and add your two cents!

B

[becc971]

what is a POW lens? my manager and i are both stumped! ... also not too sure about "comp'd" ... did you mean computed? sorry i don't speak abbreviations well!!

[Barry Santini]

POW = Position of Wear

Comp'd = (Rx) Compensated

B

[jonah]

So much has evolved since ANSI came up with standards, and frankly, they probably don't understand half of it now.

[n711]

Maybe the ANSI standards need to "catch-up" (I know dealing with a government body...good luck) when taking into consideration the clarity someone would get by a comp'd Rx I don't know how they could be considered not "with in tolerence". Maybe I should say that a different way, I know HOW they would be considered jusy not WHY!!

Did I even make sence?? Sheesh... I need to have some coffee I think!

[Randle Tibbs, ABOM]

Bear in mind that ANSI is much like the pirates code "It's a suggestion". Also, isn't ANSI revising their standards in the near future to account for compensated lenses?

[Wes]

Maybe the ANSI standards need to "catch-up" (I know dealing with a government body...good luck) when taking into consideration the clarity someone would get by a comp'd Rx I don't know how they could be considered not "with in tolerence". Maybe I should say that a different way, I know HOW they would be considered jusy not WHY!!

Did I even make sence?? Sheesh... I need to have some coffee I think!

ANSI is not a government body.

[Wes]

Bear in mind that ANSI is much like the pirates code "It's a suggestion".

Correct, except when a real government agency, like the FDA, decides to enforce some of those standards.

[Wes]

So much has evolved since ANSI came up with standards, and frankly, they probably don't understand half of it now.

The most recent publication of those standards was 2010. I know a couple of the people who sat on that committee, and I can assure you they know what they're talking about.

[n711]

ANSI is not a government body.

I said I needed coffee....

I guess this is my one mistake for the week.

[Judy Canty]

So much has evolved since ANSI came up with standards, and frankly, they probably don't understand half of it now.

I'm sure that Darryl has a pretty good handle on it.

[Barry Santini]

Bear in mind that ANSI is much like the pirates code "It's a suggestion". Also, isn't ANSI revising their standards in the near future to account for compensated lenses?

Even if they are, those of us who have immersed themselves in these compensated lenses should be asking ourselves if all our "old" stk SV jobs were, in fact, not compliant with ANSI power standards. Yet, most proved to be "satisfactory." for the clients.

B

[Wes]

I hate voting for a typo! Refractionists use lenses perpendicular to the optical axis to refract. Glasses as worn must function well for the full range of vision, which for ground based animals like us, tends to be ahead and slightly down. POW compensated lenses are very appropriate for glasses requiring tilt and/or wrap.

[Wes]

Even if they are, those of us who have immersed themselves in these compensated lenses should be asking ourselves if all our "old" stk SV jobs were, in fact, not compliant with ANSI power standards. Yet, most proved to be "satisfactory." for the clients.

B

In some cases of higher tilts/wraps/powers, stock (and other) lenses don't meet the refractionist's intent when position of wear is taken into consideration. Now, how do we explain that to the patient when another optical tells the patient they aren't within standards?

[Jason H]

Its my understanding that POW compensations are the equivalent of the Rx, once you allow for the difference in a tilted frame versus a perpindicular refraction or vertometer examination. If they are equivalent you are further away from ANSI standards if you don't compensate. It's the whole point - isn't it?

[Jason H]

Oh wait, just noticing how carefully the original question was worded.

[Barry Santini]

Its my understanding that POW compensations are the equivalent of the Rx, once you allow for the difference in a tilted frame versus a perpindicular refraction or vertometer examination. If they are equivalent you are further away from ANSI standards if you don't compensate. It's the whole point - isn't it?

Yes...that *is* my intent with this question.

B

[idispense]

The Dr intends a RX to deliver visual accuity as tested, therefore it is your job to deliver that visual accuity as worn, therefore it also follows that the Dr and his Regulator should insist on releasing the visual acuity along with the RX and optician regulators should insist on a sign off by the optician verifying that visual acuity was achieved .

Goodbye on line vendors.

[MakeOptics]

POW and Comp'd, The vision council has a document that describes all the common terms used in the industry and these two are really just a form of optical slang, kinda like "no-glare". I don't use the terms pow and comp'd because they are technical slang as well which is counterproductive, but I understand that "professionals" understand these terms so I'll play along.

ANSI, does have a provision for comp'd lenses and when a comp'd lens is supplied according to the 2010 ANSI you should check conformity to the comp'd Rx not the refracted Rx.

Looking back at historical methods, I would say that the accuracy supplied by comp'd lenses is unnecessary to most. Solid methods are being developed to identify clients that could benefit from these lenses, that's when I think the best benefit to the client will be realized.

I have also questioned the quality being produced by the everyday laboratory. I understand quality control measures are in place, but I have not seen any quality assurance measures in place. That is a very important distinction. Essilor claims that their process has been developed to provide that quality assurance but I am not a big believer since I have seen the shortcuts taken on the line in their AR production from when their flagship coating first hit the market. I think eventually every product and process succumbs to profit and margins. The easiest way to increase profits is to fudge a little which puts us back at stock lens optics.

[Barry Santini]

PhiTrace:

The importance of production engineering aside, the question is really one where we ask:

"Do you subscribe to the concept that *any* Rx, even those fitted ideally with proper compliance to corrected curve theory, may require a (recalculated?) set of Rx parameters to provide the vision as the refraction intended...assuming that the refraction is done as perfectly as the production of the lenses?"

Further, in a specific fitting situation, when those values at the primary gaze angle are recalculated from the original Rx, and that these numbers deviate from the original Rx in an amount greater than the appropriate ANSI tolerances, would the use of any lens whose labeled power is compliant, but deviates from the recalculated power at the primary gaze angle, be reasonable considered out of compliance?

BTW - Just what are the terms you prefer?

B

[MakeOptics]

PhiTrace:

The importance of production engineering aside, the question is really one where we ask:

"Do you subscribe to the concept that *any* Rx, even those fitted ideally with proper compliance to corrected curve theory, may require a (recalculated?) set of Rx parameters to provide the vision as the refraction intended...assuming that the refraction is done as perfectly as the production of the lenses?"

I don't think you can ask that question AND put production engineering aside. ANSI has largely been defined by the production side of the industry. ANY Rx is just a summation of all orders of errors present int eh patients optical system, the eye. Given that the prescription may incorporate mean higher order aberrations summed into the lower order spherical and cylindrical components that we are used to seeing ona prescription. I don't know if addressing the issues with a refraction by way of lens production is going anywhere, for most clients.

Further, in a specific fitting situation, when those values at the primary gaze angle are recalculated from the original Rx, and that these numbers deviate from the original Rx in an amount greater than the appropriate ANSI tolerances, would the use of any lens whose labeled power is compliant, but deviates from the recalculated power at the primary gaze angle, be reasonable considered out of compliance?

It depends on the patient, ultimately the satisfaction of the patient will be 100% if everyone does there job right. I don't know if at the professional level we have accomplished this simple task so that's where I would focus my attentions first and foremost. More on that later.

If you ask me the dollars they spend with me to purchase a FF lens to accomplish precision vision would be better spent with the refracter. Most of my issues with vision don't come from me or the lab choosing the wrong lenses. They come from an off prescription. Also I don't know what goals my stock lenses hope to accomplish when they are labelled best form, nor do I get that information from the FF manufacturers. I can't make a truly informed decision until I have data. I have spent my time gathering that data the dumb way. I don't think a poll is going to coax that out of me.

BTW - Just what are the terms you prefer?

B

[Robert_S]

The Dr intends a RX to deliver visual accuity as tested, therefore it is your job to deliver that visual accuity as worn, therefore it also follows that the Dr and his Regulator should insist on releasing the visual acuity along with the RX and optician regulators should insist on a sign off by the optician verifying that visual acuity was achieved .

Goodbye on line vendors.

Good idea!

[MakeOptics]

The Dr intends a RX to deliver visual accuity as tested, therefore it is your job to deliver that visual accuity as worn, therefore it also follows that the Dr and his Regulator should insist on releasing the visual acuity along with the RX and optician regulators should insist on a sign off by the optician verifying that visual acuity was achieved .

Goodbye on line vendors.

I forget where I read it, but back in the days vertex compensations were frowned upon by prescribers. ANSI has the procedure for vertex compensation listed in the document so that all vertex compensations are verifiable.

I point to these two facts, one because prescribers want their prescription filled as written, optician interpret as written "as worn". Two ANSI has made vertex compensation transparent enough where a lens that has been vertex compensated can be verified and the quality assured on the office level. With current "comp'd lenses" the lens can only be verified to the comp'd prescription provided by the lab so the quality can be controlled but not assured in this case, also the lens cannot be mathematically calculated back to it's roots the Rx or recipe.

It's this equivalent of a little of this a little of that. I know which lenses I like and trust so I have made the issue moot, but make no mistake FF lenses have many manufacturing labs that are giving the process a black eye. Ideally I love your comment, realistically it makes me sad.

[Barry Santini]

The Dr intends a RX to deliver visual accuity as tested, therefore it is your job to deliver that visual accuity as worn, therefore it also follows that the Dr and his Regulator should insist on releasing the visual acuity along with the RX and optician regulators should insist on a sign off by the optician verifying that visual acuity was achieved .

Goodbye on line vendors.

There are problems here:

1. Acuities are rarely written on the Rx.
2. Even if the target acuity is acheived, things such as subjective sense of clarity contrast as just as important, and the client will expect to achieve what they expect, no matter what the refractionist's intentions were.
3. Signing off really means signing away the client if they are not satisfied.

B

[Barry Santini]

I forget where I read it, but back in the days vertex compensations were frowned upon by prescribers. ANSI has the procedure for vertex compensation listed in the document so that all vertex compensations are verifiable.

I point to these two facts, one because prescribers want their prescription filled as written, optician interpret as written "as worn". Two ANSI has made vertex compensation transparent enough where a lens that has been vertex compensated can be verified and the quality assured on the office level. With current "comp'd lenses" the lens can only be verified to the comp'd prescription provided by the lab so the quality can be controlled but not assured in this case, also the lens cannot be mathematically calculated back to it's roots the Rx or recipe.

It's this equivalent of a little of this a little of that. I know which lenses I like and trust so I have made the issue moot, but make no mistake FF lenses have many manufacturing labs that are giving the process a black eye. Ideally I love your comment, realistically it makes me sad.

It is interesting to note that for most FF lenses, when the fitting vertex (and or refracting) vertex is ask for, it is NOT for Vertex compensation reasons. It is to help ensure optimal lens mapping.

I agree with you Phi Trace, that the end result of spectacle correction is a recipe summed of multiple layers. But where I disagree is about how much better just about everyone sees with FF SV. And FF SV allows me to imrpove fit and deliver the authentic fashion without optical comprimise.

Of this, there is no doubt in my mind.

B