PAL's, PAL's everywhere... not sure which one's for me....

[Now I See]

Hi everyone!

I'd like to know how to switch someone from one PAL to another? OK, that sounds dumb, let's put it this way, I'd like to know how to switch someone from one PAL to another, CONFIDENTLY.

What I'm wondering is, if someone comes in wearing XYZ PAL, then how do I know that ABC PAL is going to work? Should I be matching up soft designs for soft designs..."4mm" fitting cross for "4mm" fitting cross (...."2mm" for "2mm", "0mm" for "0mm")? Or should I be looking more closely at the NEW RX and Add power? Besides the obvious...preadjusting, and acurate fittings...what are other factors to take into account so that I may confidently switch someone from one pal to another. I would like to make it so that if they have problems I'm not thinking... 'could it be the switch in the design?'

[WFruit]

It's all subjective.

However, if you at least want to increase your chances of not having a non-adapt when you switch designs, then I would say that moving from soft design to soft design and hard design to hard design is your best bet. Also, if you're feeling really adventurous then: http://thelensguru.com/ is the place to go. You can look up the design your patient is currently in and compare it to what you are thinking of switching them to.

Or, you can just go Free Form and be done with it all :D.

And keep in mind that nothing is guaranteed to work every time for every patient.

[Now I See]

It's all subjective.

However, if you at least want to increase your chances of not having a non-adapt when you switch designs, then I would say that moving from soft design to soft design and hard design to hard design is your best bet. Also, if you're feeling really adventurous then: http://thelensguru.com/ is the place to go. You can look up the design your patient is currently in and compare it to what you are thinking of switching them to.

Or, you can just go Free Form and be done with it all :D.

And keep in mind that nothing is guaranteed to work every time for every patient.

Thanks...I love looking at Lens Guru! Got them on in under my "favorites" tab! Oh, how I wish going all Free Form would work for me that easily! I've dispensed a few, and so far nobody has been "wow-ed" (not with the PAL's, anyway..SV is a different story), in fact a couple of them ended up back in their original design lens...anyhoo..that's a whole other topic on another thread....

When you look through Lens Guru, do you compare the new maps they have listed there? I'm assuming that the goal with the maps is to find a design that is similar to the one the patient had been wearing (provided they like the PAL they've been wearing)

[WFruit]

Yes, it's best to try to match the map of the old lens to the map of the lens you are switching to. Or at least get them as close as possible, since no two are going to be identical. And while the "soft to soft, hard to hard" is a good rule of thumb, it's harder since a number of lens vendors started trying to combine the best of both design types in order to create that one "fit's all" progressive. And thus the lens maps are the best way to go. And I've got the site under my "favorites" as well :o.

Eventually you'll get a feel, I think, for what progressives are similar to what others, and what your patients have sucess moving into. If you want to list what you're trying to take people out of and what you're trying to put them into, we can play that game where we draw the line between the two columns that match each other :p.

Now, what Free Forms have you been using that you haven't had good luck with?

[Bill Mahnke]

Keep in mind that even if you use the same brand of progressive - as the Rx changes (add power, base curve, material, etc) so does the lens design. If a patient has been wearing the highly touted "XYZ Progressive" for 20 years, and you keep them in it - you’re really providing the same lens in name only (see pic below).

I don’t feel the lens plots are all that useful. A manufacture will show the “ideal design” of a given progressive in a Plano +2.00 add plot. That’s great, but if you add cylinder to the Rx the plot changes radically (cyl really screws up the lens design).

Patient education is the key, it's not easy because you’ve got to do it with a smile. Many of the really successful dispensers let their patients know that their visual needs and requirements have changed. They reassure the patient that both Rx and lenses are good; they insist that the patient wear their new lenses all the time. Several really strong dispensers I know tell their patient that if they fail with their new progressives it’s really their fault. It seems to work because their progressive non-adapt rates are very low, these "tough love" dispensers are well liked and respected by patients.

The following is from HOYA, this shows what happens to a progressive lens design as the add power increases:

[WFruit]

I don’t feel the lens plots are all that useful. A manufacture will show the “ideal design” of a given progressive in a Plano +2.00 add plot. That’s great, but if you add cylinder to the Rx the plot changes radically (cyl really screws up the lens design).

I agree that manufacturer maps are not useful. However, all of the maps on TLG are provided by an independent source, and are all from lenses supplied by Optiboard memebers. It's not perfect, but it's a lot more honest.

And the Hoya picture is an excellent example of why everyone should just get Free Form :)

[braheem24]

The Hoya a pic is typical E marketing without the finesse.

ie BS.

[nawsman]

A patient came in the other day and I could not for the likes of me figure out what type of pal lens they were wearing, look into the lensguru site and it was not there...can you help??

o____________o
25___________^ these are the markings, the roof top symbol is wider at the bottom. More like a rank Insignia for a Private in the army

[WFruit]

Were they Polarized Progressives? If so, then they are the iRx Pro from Specialty Lens.

See here: http://www.irxlens.com/designs

[PKCRM114]

i would argue that the best way of camparing xyz PAL to abc PAL is going to be corridor length. it gets more complicated as most premium freeform lenses have multiple if not infinite corridor options, but ergonomically that is how you can determin where they are used to looking to find the intermediate and near zones. for instance if a patient is moving from an ellipse to a premium freeform design i will tend to pick a shorter corridor regardless of fitting height, because that is what they are used to. Then they will have all of the benefit of the sharper wider vision from the digital design without the adjustment period from it being a new design.

[Now I See]

....

Thanks for this visual, Bill. I like the top part of the graphic, I try to explain this to patients, but having a visual makes it so much easier to relate.

i would argue that the best way of camparing xyz PAL to abc PAL is going to be corridor length. it gets more complicated as most premium freeform lenses have multiple if not infinite corridor options, but ergonomically that is how you can determin where they are used to looking to find the intermediate and near zones. for instance if a patient is moving from an ellipse to a premium freeform design i will tend to pick a shorter corridor regardless of fitting height, because that is what they are used to. Then they will have all of the benefit of the sharper wider vision from the digital design without the adjustment period from it being a new design.

Thanks PKCRM114!

Here's another question for you guys and gals...Let's say the xyz pal has a MIN ht of 17...does that mean that the pt will get 100% of their add power at that height?

[WFruit]

I believe that will vary by vendor. For some it is 100%, for others it's 85%. Usually I believe that it's 85%.

[opticfit]

I hate when our dispensers are afraid to switch brands in order to upgrade to freeform. If we never switched people, everyone would be still wearing Varilux VIP and Truevision.

[Now I See]

I believe that will vary by vendor. For some it is 100%, for others it's 85%. Usually I believe that it's 85%.

OK, then the next question would be, if I've measured them at 17 and that's the min for xyz PAL, should I use the xyz short version? Would that give more reading room?

I hate when our dispensers are afraid to switch brands in order to upgrade to freeform. If we never switched people, everyone would be still wearing Varilux VIP and Truevision.

LOL! Good point, or for that matter, they'd still be in bifocals! :D

[WFruit]

OK, then the next question would be, if I've measured them at 17 and that's the min for xyz PAL, should I use the xyz short version? Would that give more reading room?

Sometimes.... The problem is that it depends on which progressive.... And keep in mind that using the Short version of any progressive is going to take away intermediate space. (For example, Shamir's Autograph II 11 has such a short corridor that it's almost a true "no-line bifocal")

The safest thing to do is take the Seg Height, and then lay the glasses out on the cutout/layout chart for that particular progressive. Generally you want at least half of the bottom reading circle to be inside the lens, obviously the more the better. The other advantage to this is that you will be able to get a better feel for the "true" minimum fitting height for a lens. I've seen progressives where the manufacturer has stated that minimum height to be 18. However, lenses cut at 18 have almost no reading area. The true minimum height needs to be at least 20, and probably closer to 22.

The other issue with using a short progressive is that it is possible that the patient will not see clearly below the reading area if the corridor is both too short and too high. It doesn't happen very often, but I've seen it just enough to be aware of it. And because the progressive is "compressed" they tend to be a "harder" design, with higher amounts of distortion.

[Judy Canty]

Thanks for this visual, Bill. I like the top part of the graphic, I try to explain this to patients, but having a visual makes it so much easier to relate.


Thanks PKCRM114!

Here's another question for you guys and gals...Let's say the xyz pal has a MIN ht of 17...does that mean that the pt will get 100% of their add power at that height?

You need to ask, and sometimes continue to ask, your lens or lab reps. Some reps are there because they were outstanding cheerleaders, other have actual optical knowledge. It takes time to weed out the ones who can't help. The percentage of add power does indeed vary by manufacturer.

[One science]

Try to put together the map of the old lens with the others old lens and the new lens with the new lens, otherwise they won't be compatible.

[PAL]

I agree that manufacturer maps are not useful. However, all of the maps on TLG are provided by an independent source, and are all from lenses supplied by Optiboard memebers. It's not perfect, but it's a lot more honest.

And the Hoya picture is an excellent example of why everyone should just get Free Form :)

The maps on TLG are useful to some people, but many dispensers dismiss the maps because there are too many variations in prescriptions and how patients use or react to their new lenses.
I like to think they at least give a starting point, and when I'm dealing with a very tech-obsessed patient, they can be good to show them so their expectations are a little more reasonable.

As for FF, as with others I've seen mixed results on patients. Just looking at TLG maps you can see they are not miracles that suddenly make every single part of the lens perfect.

Number one priority for me when talking to a patient is finding out how they will use their progressives.
For example, if they are a light user of the near/intermediate zones then I focus on lenses known for wide distance zones, and don't worry too much about the others. OTOH, if they are a dual-monitor nerd, then I will really be concerned more with near/intermediate.

Comments above about corridor are of course factors to consider also. The lens size will of course be a big influence on what designs to consider (assuming you are not just going FF).

But in the end, nothing will "guarantee" a good result. You can only work to improve the chances, knowing that there is too much variation to have the slam-dunk every time.

And of course, manufacturers are full of wild claims about their new products solving every problem for every user. When reading their product brochures, a single manufacturer will often describe more than one of their progressives as the "best", meaning it's up to us to try to find out the real differences under real conditions.

[sharpstick777]

Heather,
One of the difficulties in trying to match PAL's is that you are expecting the previous dispenser to have done a perfect job. What if I sold cars on the same principle? A man drives in with a minivan and asks about a sports car, but I put him in another old minivan? Also, you miss the oportunity to improve vision and lifestyle.

I fit only digital lenses folr years, and I was switching EVERY patient. I prefer to match lens style with lifestyle regardless of what they wore previously. I switched thousands of patients over the years, and only had a1% non-adapt (most of those were first time PAL wearers). I went over 2 years without a single non-adapt at one point.

Different digital lenses have different characteristics and benefits, and when you match those to a patients lifestyle the results are almost always impressive.

[Now I See]

Heather,
One of the difficulties in trying to match PAL's is that you are expecting the previous dispenser to have done a perfect job. What if I sold cars on the same principle? A man drives in with a minivan and asks about a sports car, but I put him in another old minivan? Also, you miss the oportunity to improve vision and lifestyle.

I fit only digital lenses folr years, and I was switching EVERY patient. I prefer to match lens style with lifestyle regardless of what they wore previously. I switched thousands of patients over the years, and only had a1% non-adapt (most of those were first time PAL wearers). I went over 2 years without a single non-adapt at one point.

Different digital lenses have different characteristics and benefits, and when you match those to a patients lifestyle the results are almost always impressive.

You are absolutely right, Sharpstick. I ask if they have any concerns about the lenses they are wearing, and if they bring something up, we do some switching. But using your example, someone might say...yeah, these are OK...then I have just missed the opportunity to possibly "wow" them. I would love to see an un-biased list of PAL's and their characteristics and benefits. Yeah, I know the list would be out-dated as soon as it was printed, that's why I love O'board, you guys and gals help keep me up-to-date. But, hey, a gal can still dream about the list, can't she??

[DragonLensmanWV]

Where did you see the free form lens maps on TLG's site? There aren't any.

[Now I See]

I haven't either...can a free form lens be mapped??

[DragonLensmanWV]

No, that was my reference to PAL saying he saw them on Tony's site. Harry deliberately left out any digital or freeform lens.

[WFruit]

Well, you can map a FreeForm lens (the manufacturers do it all the time). It's just that there really isn't any point from a practicality point of view, since even lenses of the same power can be different due to POW compensations.

[DragonLensmanWV]

Well, you can map a FreeForm lens (the manufacturers do it all the time). It's just that there really isn't any point from a practicality point of view, since even lenses of the same power can be different due to POW compensations.

Not to mention custom fitting heights.