So the Dr I work for took a guy out of a Hoya ECP and put him in a comfort enhanced. Now the guy has a good bit of distortion in the peripheral vision.
+1.75 -.25 x 15
+1.75 sph
+2.00
34/33.5
23 high
We're trying to get him back in the ECP, but the lab (Essilor) may not be able to handle this. As a back up would an InTouch be a good substitute, more would a one of the Sekos be better?
What are his lifestyle needs? Is the peripheral the distance peripheral? How's his intermediate with the new lens?
From what I know (I got handed this second hand) Moderate computer use, intermediate is not an issue, it's the peripheral in general he's complaining about. Frame size is almost the same. I think 2mm bigger on the A haven't had a chance to check panto or anything.
Define peripheral vision, that is, at what angle of gaze.Originally Posted by Boldt
Post old Rx.
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.
First thing to do verify the PD and OC (verify no unwanted prism in either pair), then match the fit, esp Vertex and Panto from new pair to old. The other things is to see if there was a material change.
The Comfort is emphasized for reading, which means as you make the reading wider the distance narrows. It has one of the widest reading zones on the market, as such, its also one of the narrowest distances, esp in high adds. The Comfort is an adaptive design that narrows the distance zone with each increase in Add power, but keeps the reading zone wide.
ECP is a hard design, with a wide intermediate for a standard lens, but as a result if has one of the widest areas of a traditional ground lens. It also has more base curve options than the Comfort, so you could be looking at anyone of a dozen issues.
Not knowing what his lifestyle needs are though its impossible to say where you should go, once you determined the problem.
Did the doc raise the add, from say, +1.00 to +2.00? That alone could cause the symptoms.
An add power bump is likely at this stage of presbyopia. An increase of .25 D or more would be the most likely cause for a difficult adaptation/off-axis blur.
The ECP is a soft design.ECP is a hard design, with a wide intermediate for a standard lens, but as a result if has one of the widest areas of a traditional ground lens. It also has more base curve options than the Comfort, so you could be looking at anyone of a dozen issues.
The New Comfort has a slight shorter corridor than the original comfort. The Contour plot below is the old Comfort and should look similar to the new design.
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.
What progressive lens has less distortion in the peripheral area? My customer will use the sunglasses for driving and playing golf.
"What car has a good engine?"
Sincerely,
Chad Sobodash ABO-AC
Update:
Doing the ECP again, but looks like the segs where a tad up and out. (1mm up and 1.5ish out on left and 1 on rt.) I retook everything so now just to wait.
Thank you for the help.
Robert, I keep seeing those topographical maps on progressives, how do you read them? I have guesses, but would rather know.
Optician2601: I've had great results with the Shamir Golf lens in the past, and the Oakley version is done quite well also.
I've successfully used Shamir Auto 3 to switch all previous lens wearers with all measurements...vertex, no, panto done with an essilor clear measuring device. Shamir is available in all materials, base curves, colors of polarized, even copper tone grey (my fave) I've had a one eyed man with from hoya and hug me. Happiest guy in the world! Make sure you ask the life style questions to set best fitting height. I usually stick with 18 for more peripheral, but bump it down to 16 or less if they do a lot of computer work. I have a chart that splits up the amount of each viewing area from Shamir. Varliux S Series and S Series Fit do the same, but they are more expensive and don't have as many options with lens or AR availability. Shamir keep continuity from everyday wear to sun wear to many multiple pair. Good Luck! It's a whole new world for high add powers! I always use Trivex when possible. High plus RXs can be drilled at a razor thin edge with no breakage like HI or stretching/cracking like poly. Not sure if Essilor had the S Series in Trivex or high base curves. Try Walman Lab for all availabilities.
Trust me if I had my way the guy would have been in an auto 3 no questions. And trivex has always been my go to for lenses. :^)
The more the addition is increased the larger the distorted parts
I just love this discussion.
The more the addition is increased the larger the distorted parts on the lens, and the older is your customer.
These are 2 factors that are harder to adjust for people that are getting older.
It is not a matter of manufacturing, progressive curves produce distortion whatever make they are, which any optical engineer can certify.
It was like that when Essilor introduced the Varilux 50 years ago and has not changed with the exception of that every lens manufacturer now makes his own distorted progressives and everybody makes good money selling lenses that have 40% unusable lens areas.
Wow , nice power&cylinder Map could you share more please Mr.Robert Martellaro that was good knowledge
+1+1
The plots are from a collective effort of Optiboarders and Rotlex from about 5 to 10 years ago. I wasn't involved.
Contour plots can give us a general idea about the lens design, but you'll learn much more if you wear the lens, experimenting with both an emerging or somewhat younger presbyope (adds from +1.25 to +1.75, and an older presbyope (adds from +2.00 to +2.50). Make two identical, except for PAL design, pairs of eyeglasses so that the wearer can't tell which pair is which (no peaking at the reference marks!). Try to get a mix of moderate myopes and hyperopes, ideally more than 3 D. Evaluate both short and long term performance.
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.
Check panto , wrap, vertex and base curve. These matter more than which design, often.
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