Progressive Frustration

[drk]

This has happened to me several times, and I can never seem to get at the root of the problem.

Typical scenario: person picking up some form of progressive lens. Person claims that he has to turn head to left or right to see more clearly. I check monocular pd's. I check vertex and panto. I even check for some weird, asymmetric convergence by checking near pd's. I check the clear zone by asking him to turn his head to either side, monocularly. Nothing looks wrong or asymmetric, but the guy just has to turn his head to one side to see clearer when both eyes are open!

What am I missing? The need for an inset specific to this guy? The guy today had a 66.5/61.5 pd (33/33.5 and 30.5/31), thus requiring a 5 mm total inset, and had to turn his head to the left in his Sola Smart Segs. I know the majority of his bit***** was about a more limited field of view than his old FT's, but the head turn thing? If they were generically inset not enough (say, only 4 mm, per lens design), then the relatively outset reading area would cause you to try to turn your head, right? And maybe the patient notices it in only one direction more than another?

In other words, is this problem from people with greater and lesser near insets than is standard for a given progressive design? If so, then people with big pd's (approaching 70mm) would need to have more inset at a given reading distance, and complain of turning to the temporal portion of the lens, and small pd people would have to have less inset, and would complain of turning to the more nasal part of the lens?

Another confounding factor may be their eye muscle balance. What if it's also related to whether they're eso or exophoric? Thus, an overly outset exo may be cool with it, but a overly outset eso would throw a hissy. And vice-versa.

Any lens design geniuses out there? Any salty old opticians?

[chip anderson]

Did you inset them individually for each P.D. or did you put both P.D.'s the same even though the monocular P.D.'s differed widely?

Make sure you have a lot of pantoscopic angle (about 8+ degrees). Had a similar problem with a patient that the doctor's office (not affiliated with my dispensary) refers to as a "nut case." Did a few adjustments and the woman still complained she was "one eyed" and could see through either lens by tilting here head to the side but not see through both together. Checked all measurments (fine), found one lens to be 2 degrees off axis which I corrected, kept glasses for a week (during which the patien thought they were in the lab being evaluated and re-made, which was my origional intention) but after I and a few colege compeditors agreed that all was as it should be, added a little more pantoscopic angle, fiddled with them, brought them as close to eye as possible without rubbing lashes or eyeballs and the woman says she is cured.

Chip:)

[ziggy]

Doc, you might also try adding some extra face form. Most of the time ,I've found it has to do with, as you suggesetd, has to do with the individual inset. Are you using a PD stick or a digital CRP? Good luck!

[Joann Raytar]

Another confounding factor may be their eye muscle balance. What if it's also related to whether they're eso or exophoric? Thus, an overly outset exo may be cool with it, but a overly outset eso would throw a hissy. And vice-versa.

I've run into this a couple of times but was able to get the patients comfortable comfortable by favoring their near PDs somewhat when I decentered horizontally. What are the powers and what progressive did you fit the patient with?

[Robert Martellaro]

DRK,

I think it's strictly a brain thing. Have you noticed that the client can't recreate the issue on a follow-up? PALs offer the brain an extremely complex if not a "messy" image to fuse. I suspect that some folks have a visual cortex that can't adapt as well or as quickly as others. I tell my clients that this is normal, that they can expect this to clear up within 24 to 48 hours. Usually it's gone the by the following morning.

Robert

[shanbaum]

I gather this is at near? What's the RX?

You mention "an inset specific to this guy" - that would be the normal way to fabricate a Smart Seg (is it not?); how was this ordered?

[Clive Noble]

I'm going to be very cynical and cutting only because it's happened to us frequently.....

So the Pt. has to move his head, or feels uncomfortable which he/she didn't in the old VIPs or AO Pros, you, as the professional have turned your brain inside out to find the cause, and in the end say, "we'll just have to remake the lenses"

"Ahhhh...." says the Pt. "In that case I would like to choose a different frame, everyone tells me this one doesn't suit me!!!! "

Hasn't this happened to you???????

[mrba]

I'm going to be very cynical and cutting only because it's happened to us frequently.....
So the Pt. has to move his head, or feels uncomfortable which he/she didn't in the old VIPs or AO Pros, you, as the professional have turned your brain inside out to find the cause, and in the end say, "we'll just have to remake the lenses"
"Ahhhh...." says the Pt. "In that case I would like to choose a different frame, everyone tells me this one doesn't suit me!!!! "
Hasn't this happened to you???????

You are worthy Clive!

[chip anderson]

Now Clive:

You could have covered yourself with: "New frame, of course. And since you didn't like the last one I'll even give you 10% off on the new glasses! And if you like I'll even dye your old lenses into sunglasses for free!

Chip
In every situation there is oportunity.

[rdcoach5]

This has happened to me several times, and I can never seem to get at the root of the problem.

Typical scenario: person picking up some form of progressive lens. Person claims that he has to turn head to left or right to see more clearly. I check monocular pd's. I check vertex and panto. I even check for some weird, asymmetric convergence by checking near pd's. I check the clear zone by asking him to turn his head to either side, monocularly. Nothing looks wrong or asymmetric, but the guy just has to turn his head to one side to see clearer when both eyes are open!

What am I missing? The need for an inset specific to this guy? The guy today had a 66.5/61.5 pd (33/33.5 and 30.5/31), thus requiring a 5 mm total inset, and had to turn his head to the left in his Sola Smart Segs. I know the majority of his bit***** was about a more limited field of view than his old FT's, but the head turn thing? If they were generically inset not enough (say, only 4 mm, per lens design), then the relatively outset reading area would cause you to try to turn your head, right? And maybe the patient notices it in only one direction more than another?

In other words, is this problem from people with greater and lesser near insets than is standard for a given progressive design? If so, then people with big pd's (approaching 70mm) would need to have more inset at a given reading distance, and complain of turning to the temporal portion of the lens, and small pd people would have to have less inset, and would complain of turning to the more nasal part of the lens?

Another confounding factor may be their eye muscle balance. What if it's also related to whether they're eso or exophoric? Thus, an overly outset exo may be cool with it, but a overly outset eso would throw a hissy. And vice-versa.

Any lens design geniuses out there? Any salty old opticians?

Check his pupil size-larger pupils require very bright reading light , as would patients with emerging cataracts
Bob Taylor

[For-Life]

Check his pupil size-larger pupils require very bright reading light , as would patients with emerging cataracts
Bob Taylor

I sure hope DRK is not dealing with this customer three years later

[ferch_ctw]

Amen.