Made a new pair of glasses for a client. Half diopter increase in distance. Half diopter increase in add. Long corridor fit at 20. Distance and reading are way better than old pair but can't find mid range in them. Old pair was a short corridor that she wore with no problem. Throw me some ideas please.
What's the Rx?
I would lean towards putting the pt back in a short corridor. Depending on which one he/she was in prior, a lot of short corridors have the feeling of a wider intermediate because the "squeezing down" of the corridor actually pushes some of the marginal astigmatism out of the way.
Just my $.02 without knowing anything else about the script/glasses/pt.
I've considered that. Have quite a bit of frame to work with and with the increase in add up to 225 it seemed like the right thing to do. She says she's been wearing for a week yet her eyes and brain don't seem to be dealing with it very well at all.Originally Posted by DC Optix
I always have that problem - I simply can't wear mid/long corridor PALs. Then I have esophoria and the short corridor design just behaves better for me.
Previously underminused at distance? Obvious answer would be that the distance zone was the intermediate zone.
Underplussed at distance and near? The entire near zone was the intermediate zone.
Either way you lose! Computer lens is next course, of course.
As drk said, .50 D more minus or less plus on the distance will do that. It's like the rob peter to pay paul idiom: you have to take away some intermediate utility to improve the distance. Not much that can be done now except grin and bear it, or make two pair, with one being the manifest Rx and the other a room distance or computer Rx. Some might switch between the old and new Rx, most folks adapt by relearning head and eye movements.
However, your second post states that she's still ucomfortable after a week. I would consider getting the doctor involved at this point if you think she's over-minused.
Science is a way of trying not to fool yourself. - Richard P. Feynman
Experience is the hardest teacher. She gives the test before the lesson.
It's 50 more plus in the distance. It seems like it should make it easier. Her doc isn't being much help, basically said that we must have measured them incorrectly. The heights are fine but this didn't really instill any confidence in her. She's gonna bring in her old pair for us to check out to see if there's anything odd about the way her old pair was fit. Old pair was a poly LC Accolade. New pair is a Definity. Simple rx minor cyl.
Then I agree with the doc. PAL design and lack of communication tops the list.
Science is a way of trying not to fool yourself. - Richard P. Feynman
Experience is the hardest teacher. She gives the test before the lesson.
Lack of communication?
The half diopter of add will also decrease the intermediate size. Try a short corridor with wide channels like the Adage.
DragonlensmanWV N.A.O.L.
"There is nothing patriotic about hating your government or pretending you can hate your government but love your country."
Let's do the math, then.
If her new add is +2.25, then her old add was +1.75 short corridor.
If her new distance Rx is, say +0.50, it used to be plano.
Old Rx: plano/ +1.75
New Rx: +0.50/+2.25
Through old add: effective add +1.25, perfect for the computer and fit high and in a short corridor!
Her problem is that now she HAS to use an intermediate zone (and she's never had one or needed one, before), and that's usually not good for these patients, anyway.
I'd simply get her a computer lens or let her use the LC specials, and leave her general purpose PALs as is.
Just as a general rule, here's how I think we should roll:
For presbyopic (not emerging, >=+2.00) computer users that are desk-toppers (and not I-padder/lap-toppers), they need a general purpose PAL. They should be warned that they may have better success with a dedicated computer lens, and in your 2-wk phone followup, you should ask how they're doing with that.
Last edited by drk; 11-18-2010 at 10:05 AM.
Thanks DRK. Gonna roll with that.
If she liked the Accolade better, why not switch her back to it? It should work well at 20. Though I find it odd she can't find the intermediate in a Definity, it has a good intermediate area.
Maybe the increase in the distance and near is making the intermediate too strong? If her intermediate distance that she works at is a little further out then a stronger intermediate area might not work well. She will have to bring everything in closer then she is used to.
Sorry for being tactless- I'm a little on edge lately. In addition to the old and new lens design, include a thorough client history (old and new Rx, health, VAs if available and pertinent), including the type and frequency of intermediate tasks, the object (monitor, sheet music, etc.) position including the distance and vertical height, and the client's symptoms in their own words. "Can't find mid range" is too vague.
BTW, drk's analysis is spot on in both scenarios. However, as mentioned above, there is still a lot of missing and essential data.
Drk- you know more about progressives, presbyopia, and practical optics than almost every optician that I know. Impressive.
Science is a way of trying not to fool yourself. - Richard P. Feynman
Experience is the hardest teacher. She gives the test before the lesson.
You are kind.
What makes optometry effective and opticianry effective is when we work together. It's difficult to know both fields completely, but together we can do good stuff!
You're both great. As it stands I think with a little explanation from the info I got from you I hope I can make this work. Hopefully my follow-up will be cheerful. :cheers:
Agree with drk and Robert, but still think a shorter corridor with a wide intermediate would fix the problem. I like the Seiko Supercede WS for this purpose, exactly.
So check this out. Our client got into a little car accident (not related to her glasses). Insurance is gonna cop to a brand new pair. We get a fresh start!
I consider her misfortune to be an exceptional birthday present. :)
Here's the follow up. Client adapted to RX, donated old glasses. Bought a new frame in the same style and different colour to put the lenses that her insurance replaced into.
Thanks for the update. So how long did it take for her to adapt to the new RX?
I didn't ask her specifically but the time line would indicate a couple weeks.
I thought you were on vacation
It's when I do my best work! :)
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