# Optical Forums > General Optics and Eyecare Discussion Forum >  Which Progressive has a wide corridor?

## MIOPE

I have this patient that has been wearing progressive with RX -1.00 add 2.00 for more than 6 years. Now his prescription is -1.75 add 2.25.
He does a lot of work on a regular computer (not a laptop) and feel comfortable with his old progressive that and rejects the new ones because now he has to use the corridor for computer monitor distance but admit that hes distance vision is a lot better. 

I know this is a old story and in most cases it has been solved with two pair of glasses because progressive are good for different distance but not the best solution for special cases. This patient has a wide far distance part of the old progressive with a prescription that is appropriate for then computer (monitor) distance.  
But maybe there is a better solution that I do not know.

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## braheem24

Personally I would advise him to keep his old glasses at the computer desk.  Nothing will beat his current +.75 add in the distance.  

Depending on his expectations a possible compromise would be to give him a -1.75/+1.00 add where he would have both distance and intermediate and take off his glasses for closer work.

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## Happylady

Can he just use his older glasses for the computer?

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## MIOPE

thanks for answering. The options mentioned are possible.
I would like to know if there is a progressive design with  a extra wide corridor and good far and near distance area?
No matter if it is a digital design. 
We progressive wearers has been instructed to point with the nose what we want to see on focus. Move your head and not your eyes.
Maybe someone has already a less restrict progressive. does it exist?

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## braheem24

If you're setup to do digital with iot already you should have all of the designs below available to you.

some are more optimized for distance/intermediate and/or reading.

http://www.iot.es/designslist.html

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## Happylady

The Esilor Definity has a wider corridor than most progressives but no progressive is going to have an extremely wide one. Also, no matter how wide it is, if he is looking straight ahead at the monitor he will have to raise his chin to see it with his new correction. 

Is is it possible to have the monitor low enough his eyes are right at the top of it?

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## Don Gilman

> I have this patient that has been wearing progressive with RX -1.00 add 2.00 for more than 6 years. Now his prescription is -1.75 add 2.25.
> He does a lot of work on a regular computer (not a laptop) and feel comfortable with his old progressive that and rejects the new ones because now he has to use the corridor for computer monitor distance but admit that hes distance vision is a lot better. 
> 
> I know this is a old story and in most cases it has been solved with two pair of glasses because progressive are good for different distance but not the best solution for special cases. This patient has a wide far distance part of the old progressive with a prescription that is appropriate for then computer (monitor) distance.  
> But maybe there is a better solution that I do not know.


Give him a -0.75 in the distance and a +1.25 add

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## Robert Martellaro

> I have this patient that has been wearing progressive with RX -1.00 add 2.00 for more than 6 years. Now his prescription is -1.75 add 2.25.
> He does a lot of work on a regular computer (not a laptop) and feel comfortable with his old progressive that and rejects the new ones because now he has to use the corridor for computer monitor distance but admit that hes distance vision is a lot better. 
> 
> I know this is a old story and in most cases it has been solved with two pair of glasses because progressive are good for different distance but not the best solution for special cases. This patient has a wide far distance part of the old progressive with a prescription that is appropriate for then computer (monitor) distance.  
> But maybe there is a better solution that I do not know.


I don't see how a wider corridor would help. The key is getting the power correct at the primary gaze, looking straight ahead at the screen. 

If they refuse two pair (including power layer clips), you're only hope is to shorten the corridor to minimize, but not eliminate posturing. Of course shorter corridors are narrower both horizontally and vertically, with huge swings in power/aberration, resulting in noticeable blur if you don't hold your head just right. I can sustain that kind of posture for a few minutes, enough to read a short article or email. YMMV. 

I can use a small flat head screwdriver on phillips screw, but it's clearly the wrong tool for the job, usually resulting in a stripped head or worse. Present a similar analogy to your client, maybe personalizing it around your client's work or hobbies.




> Can he just use his older glasses for the computer?


Simple enough in this case, although it does leave the desktop overplussed, and underplussed at the monitor, depending on the distance. All bets are off if the lenses are scratched or the frame is not serviceable and/or looks horrible.

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## drk

All the above is great advice.

Is the Seiko Surmount the closest thing available to the "magic lens" envisioned in the original post?  It's distance plus a "V" shaped corridor/near zone (wider to narrower), IIRC.

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## Robert Martellaro

> All the above is great advice.
> 
> Is the Seiko Surmount the closest thing available to the "magic lens" envisioned in the original post?  It's distance plus a "V" shaped corridor/near zone (wider to narrower), IIRC.


No. Intermediate zone width is irrelevant. It's either task eyeglasses or grin and bear it, depending on object height/distance, frequency of use, amplitude of accommodation, etc.

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## MIOPE

Wider intermediate zone means less need to move the head to see at the sides. Wich is closer to a natural behavor.
Maybe the lens I am refering to has not been invented jet.
I ask because if i do not know it does not means it does not exist.

Drk. I will take a look at the Surmount.

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## Robert Martellaro

A wider corridor solves nothing, unless you're a cook, checkout clerk, etc.

Most corridors for adds over +1.75 are about 3.5mm wide (constrained by .50 DC limits, 50% add power). The widest that has been tested (Definity) was about 4.5mm (+2.00 add). 

Sheedy JE. Progressive addition lenses—matching the specific lens to patient needs. Optometry 2004;75:83-102.

A wider corridor is a longer corridor, requiring even more chin lift to bring the screen into focus. See the illustration below.

Refract the work distance, and use a multifocal with a wide distance zone. See Don Gilman's example above.

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## Don Gilman

> A wider corridor solves nothing, unless you're a cook, checkout clerk, etc.
> 
> Most corridors for adds over +1.75 are about 3.5mm wide (constrained by .50 DC limits, 50% add power). The widest that has been tested (Definity) was about 4.5mm (+2.00 add). 
> 
> Sheedy JE. Progressive addition lenses—matching the specific lens to patient needs. Optometry 2004;75:83-102.
> 
> A wider corridor is a longer corridor, requiring even more chin lift to bring the screen into focus. See the illustration below.
> 
> Refract the work distance, and use a multifocal with a wide distance zone. See Don Gilman's example above.


Great answer. Why keep asking about a wider corridor and having the patient still have to tilt there head back when they can have 180 degree in the top and no stiff neck.

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## Tallboy

I usually explain to people like this that guys who work construction can't wear their nikes on the jobsite, although they are comfortable and great - their job deserves specialized shoes - just like a full time computer terminal worker deserves specialized eyewear (and desk and chair and computer monitor positioning as well)

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## AngeHamm

> No. Intermediate zone width is irrelevant. It's either task eyeglasses or grin and bear it, depending on object height/distance, frequency of use, amplitude of accommodation, etc.


Truer words have never been spoken.

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## AngeHamm

> I usually explain to people like this that guys who work construction can't wear their nikes on the jobsite, although they are comfortable and great - their job deserves specialized shoes - just like a full time computer terminal worker deserves specialized eyewear (and desk and chair and computer monitor positioning as well)


Also excellent. I'm stealing this analogy.

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## Happylady

> No. Intermediate zone width is irrelevant. It's either task eyeglasses or grin and bear it, depending on object height/distance, frequency of use, amplitude of accommodation, etc.


I don't agree. I wear a +2.50 add and have never had a computer lens and use progressives with computers, both desktops and laptops, with no issue. The height of the screen is key. It can't be too high, ideally the top of the computer monitor needs to be lower than a straight ahead gaze. I wish there were more adjustable monitors.

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## Robert Martellaro

> I wish there were more adjustable monitors.


Ah, so that you don't have to lift your chin and squint with your general purpose eyeglasses? :Tongue: 




> I wear a +2.50 add and have never had a computer lens and use progressives with computers, both desktops and laptops, with no issue. The height of the screen is key. It can't be too high, ideally the top of the computer monitor needs to be lower than a straight ahead gaze.


You're clearly an outlier; I see less than about 5% of my clients who are like you, even when the add range is extended down to two diopters. Your good fortune is probably due to pupil diameter, reserve accommodation, object size/height/distance, and a _high tolerance for blur_. 

WRT screen heights, desktop monitors are large enough now that the center of the screen is at or slightly below the primary gaze, exactly where my 27" iMac sits as I type this. Some of my clients have two, sometimes three of these side by side. The radiologist I fit last week uses a 45" monitor.

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## Happylady

> Ah, so that you don't have to lift your chin and squint with your general purpose eyeglasses?
> 
> You're clearly an outlier; I see less than about 5% of my clients who are like you, even when the add range is extended down to two diopters. Your good fortune is probably due to pupil diameter, reserve accommodation, object size/height/distance, and a _high tolerance for blur_. 
> 
> WRT screen heights, desktop monitors are large enough now that the center of the screen is at or slightly below the primary gaze, exactly where my 27" iMac sits as I type this. Some of my clients have two, sometimes three of these side by side. The radiologist I fit last week uses a 45" monitor.


Actually, I don't have to lift my chin on the computers I use, they are low enough. I was thinking of the many people who do have monitors that are too high. 

My pupils are small and I don't have a high tolerance for blur. I am using the channel to see the screen, if I turn my head slightly or lower my head it does get blurry. 

I'm sure it wouldn't work well if I used more than 1 monitor. And I do recommend computer lenses, I think they are great in many situations. They wouldn't work that well for me because I use my distance vision at the same time and I like it to be clear and not blurry like it would be with a computer lens.

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## Joe Zewe

The head tilt issue and narrowness of the progressive corridor is why we came out with the Chemistrie Blue add power lens layers.  They work great and I wear them whenever I am using a computer.  I am a +2.00 add for reading and wear a +1.00 Chem Blue when working on the computer.  But I am biased on the issue.

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## CCGREEN

First thing I do is ask the pt to explain to me for WHAT and HOW they are going to use the glasses. Then I kick back and HUSH. I listen to what they are trying to explain to me. Give them all the time they need and say NOTHING till they are finished.

Next I tell them that I HEARD what they are trying to explain. And then I let them know that I now am going to ask them some leading questions just for more information and to determine we are on the same page. And that we are no longer 20 years old and there are no lenses or frames out there that are going to let us see as we did when we were 20. There will have to be compromises made. The pt will need to choose just what works for them at the moment and to use the correct tool/glasses/Rx.

I then let them know that we have several options to chose from, several directions to take this to try and accomplish what they want. Me being the professional will then choose the right lens/Rx/frame to help the pt accomplish what they are attempting to do.

In summary. Educate the pt first. Change their expectation if need be to something more realistic. Then make the best choice for the patient via Rx, lens design, frame, or all three.  
That's why they come to us. For guidance, NOT for us to take what is available and try to "adapt" it, and try to make it accommodate them. Let the patient adapt and acclimate to what is avaliable for what they are trying to do. Then when something better comes along excitedly introduce it to them.

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## Robert Martellaro

> Actually, I don't have to lift my chin on the computers I use, they are low enough. I was thinking of the many people who do have monitors that are too high.


They're pretty much all too high, except the small laptops and tablets.




> My pupils are small...


There you go (depth of focus).




> I don't have a high tolerance for blur


In a previous post you said you couldn't tell the difference between a Navigator Short and a Zeiss Individual 2. I'm not trying to be critical, some of my clients are the same way, including my spouse; I can put just about any PAL design in front of her eyes (plano add 2.25) and she's happy. She does have +.75 Chemistrie Clip though. 




> And I do recommend computer lenses, I think they are great in many situations.


Got it. I thought you were saying that task eyeglasses, especially computer eyeglasses, were unnecessary for desktop monitors. 




> They wouldn't work that well for me because I use my distance vision at the same time and I like it to be clear and not blurry like it would be with a computer lens.


Try a lower power, +.50 or +.75. Room distance is reasonably clear, and if your not paying attention, you might even hop in the car and drive away before you realize your mistake.

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## Happylady

> They're pretty much all too high, except the small laptops and tablets. 
> 
> In a previous post you said you couldn't tell the difference between a Navigator Short and a Zeiss Individual 2. I'm not trying to be critical, some of my clients are the same way, including my spouse; I can put just about any PAL design in front of her eyes (plano add 2.25) and she's happy.


I agree, many desktops are too high, but the one I use at work isn't. 

And I do like sharp and clear but the Nav Short is as clear as the Zeiss and my Varilux S. I can't tell the difference, none are clearer than the others.  All are slightly blurry off to the side and the lower corners are blurrier still, but I don't notice it unless I look for it.

Do you wear progressives?

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## sharpstick777

> All the above is great advice.
> 
> Is the Seiko Surmount the closest thing available to the "magic lens" envisioned in the original post?  It's distance plus a "V" shaped corridor/near zone (wider to narrower), IIRC.


The Surmount WS is wider at the intermediate than many office type lenses, its probably the best lens for your patient.

As power increases (either distance or reading) field width decreases in the same design, any design.   He had an increase in both, thus the narrower field.

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## sharpstick777

> A wider corridor solves nothing, unless you're a cook, checkout clerk, etc.
>  .


I would highly but respectfully disagree.  After central acuity (very easy to achieve, even in traditional lenses), usable width is the most important factor of a lens for 2 reasons.  

1) eyes move.  The first response to a change in focal length is ocular, not orthopedic (neck) (that response will very by hyperopes and myopes to some degree.  We are not birds.

2) moving the first point of distortion farther away from the foveal cone will always reduce the patients perception of swim or sway.  It will result in more natural vision and movement.  This can only be achieved by lowering the corridor entry point, and widening that entry point.  (although this results in other compromises further down in the lens).  

3) a wider intermediate is often the first clue of a great progressive design.  what is a progressive without its corridor?  And what is a corridor without usable width?

4) Sheedys study you quoted uses width as the only criteria for zone utility.  Its incongruous to quote that report and say width doesn't matter, to Jim, it mattered enough to do an entire study around it.  

Intermediate Width, since I have dual monitors and use both my left and right hands is my primary criteria for a progressive lens.  I can multi-task much better.

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## drk

So you love you some Surmount?

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## Robert Martellaro

> I would highly but respectfully disagree.  After central acuity (very easy to achieve, even in traditional lenses), usable width is the most important factor of a lens for 2 reasons.  
> 
> 1) eyes move.  The first response to a change in focal length is ocular, not orthopedic (neck) (that response will very by hyperopes and myopes to some degree.  We are not birds.
> 
> 2) moving the first point of distortion farther away from the foveal cone will always reduce the patients perception of swim or sway.  It will result in more natural vision and movement.  This can only be achieved by lowering the corridor entry point, and widening that entry point.  (although this results in other compromises further down in the lens).  
> 
> 3) a wider intermediate is often the first clue of a great progressive design.  what is a progressive without its corridor?  And what is a corridor without usable width?
> 
> 4) Sheedys study you quoted uses width as the only criteria for zone utility.  Its incongruous to quote that report and say width doesn't matter, to Jim, it mattered enough to do an entire study around it.  
> ...


In context (read the first post), the intermediate zone width is not relevant.

Point #2 describes the power profile and shape of most modern PALs from the last 15 years. Remember when we had to lower the fitting point below the pupil center because the power changed to soon? 

Sheedy, Hardy, and Hayes measured zone widths, zone areas/sizes, unwanted astigmatism, and minimum fitting heights. My point was that the 4mm wide average intermediate zone width is insufficient for prolonged tasks, especially if posturing is required.

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## Judy Canty

Surmount is arguably one of the best PAL designs currently available. One of my accounts just refitted a Hoya iD Lifestyle wearer (with a -3.00 cyl) in Surmount and the patient is "deliriously happy".  The account is happy because the margins are so much better.

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## sharpstick777

> Point #2 describes the power profile and shape of most modern PALs from the last 15 years. Remember when we had to lower the fitting point below the pupil center because the power changed to soon? 
> .


When you start mapping FF lenses, some of the newer designs go way beyond what was done even 5 years ago to lower and outset the first point of contact with distortion, by using a V entry into an adjusted corridor power (reduced power slope for the first 5-6 mm of entry.  Although this does compromise reading (and PC computer areas), it pushes the first point of contact with distortion about twice the distance of even some really good lenses.

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## sharpstick777

> My point was that the 4mm wide average intermediate zone width is insufficient for prolonged tasks, especially if posturing is required.


Then I misinterpreted your comments.  The Surmount WS can offer over 35mm of usable intermediate zone (it will vary by add and distance power, and will be subjective based on a individuals tolerance to yoked prism, and their tolerance for the flatter base curves the Surmount pulls).

4mm is very insufficient, but a lens like the Surmount can exceed that dramatically.  Even my hard T shape lenses (Seiko Supercede WS) can give 10mm in low adds, but at the cost of higher transitional zone distortion.

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## drk

Great Sharpiestick, you speakum different tongue than Tonto.  What is source of vast knowledge?

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