# Optical Forums > General Optics and Eyecare Discussion Forum >  Mono vision glasses?

## Happylady

Does anyone ever do monovision glasses for their patients that wear monovision contacts? If you have, what was the outcome?

I always have done progressives/bifocals or just single vision(for myopes). I had a patient ask for her glasses to be done in monovision and I was wondering if anyone else ever does that.

----------


## Grubendol

I've done it for readers over mono contacts and it's always worked well.

----------


## Ory

I've done it.  Some people will not tolerate it despite their mono CLs.  Remember to decenter the near lens PD based on a monocular PD measurement.

There was a discussion not too long ago that brought this idea up: link

----------


## Framebender

We often made mono glasses for people who had mono surgery.  The point there was to give them back their depth perception for driving at night.  It almost always worked.  Probably only 1 in 10 puked.  So not bad.

Good luck!!

----------


## Happylady

I wasn't clear enough. I meant doing monovision glasses for when they aren't wearing their contacts. Does anyone do this rather then progressive or bifocals?

----------


## Dave Nelson

You can do monovision glasses, but with essentially the same limitations as with contacts, or horrors, monovision refractive surgery. The spectacle add plays a big part in determining success. There is a limit to what disparity people will tolerate, independant of image size, although it varies from one person to the next, but in my experience many people are uncomfortable with a disparity greater than about 1 D, and can often adapt to 1.5D. Emerging presbyopes can benefit from monovision spectacles the most, with absolute presbyopes being very poor candidates due to the higher add powers in the rx. Eventually, presbyopes must be introduced to progressives, and, as you know, its an easier road to start with lower add powers and work your way up, than to jump into them with a 2.50 add. I think there is a very limited benefit from monovision spectacles, and its limited to emerging presbyopes who want to "put off" the progressives for a year or two.

----------


## eyeglsman

We have one patient in our practice that wears monovision glasses, when his cl are out. He has been very sucessfull for the last 12 years with monovision glasses.

----------


## chip anderson

If the patient is capable of steropsis (and you are talking about a pair of glasses to wear without contacts in lue of bifocal glasses) it ain't got a snowballs chance in ......    Think again about distortions and mental confusion that will result as patient looks down from center.  Concider the image size difference (if the add is over .75).   Sell 'um some bifocals.

Chip

----------


## Happylady

> If the patient is capable of steropsis (and you are talking about a pair of glasses to wear without contacts in lue of bifocal glasses) it ain't got a snowballs chance in ...... Think again about distortions and mental confusion that will result as patient looks down from center. Concider the image size difference (if the add is over .75). Sell 'um some bifocals.
> 
> Chip


But many patients have rx differences of more the .75 diopters with no problems. I can see problems if the rx differences is very great, more then 2.50 or so, but not with .75. 

Also, since they would be single vision the patient can lower their head and look through the center just like patients do that wear distance rxs with lots of differences in the prescription. I never use slab offs in single vision even with significant prescription differences because of this.

----------


## chip anderson

I still say it ain't gonna work.  
However I have a question:  Why in the H would anyone want to make a pair of monovision glasses (glasses to offsett the effects of monovision contacts [which I also think is usually a bad solution to presbyopia] I understand.  But why monovision glasses, it surely can't be because the optician is too lazy or lacking the skills to make bifocal glasses.  Why not let the patient see both distance and near with steropsis?
Or phrased more delicately, _what's the point of monovision glasses?_

And I certianly wasn't advocating a slab off in "monovison glasses."

Chip

----------


## Happylady

> I still say it ain't gonna work. 
> However I have a question: Why in the H would anyone want to make a pair of monovision glasses (glasses to offsett the effects of monovision contacts [which I also think is usually a bad solution to presbyopia] I understand. But why monovision glasses, it surely can't be because the optician is too lazy or lacking the skills to make bifocal glasses. Why not let the patient see both distance and near with steropsis?
> Or phrased more delicately, _what's the point of monovision glasses?_
> 
> And I certianly wasn't advocating a slab off in "monovison glasses."
> 
> Chip


Okay, this is what made me think of this. As I stated, I have never done it, but I have a patient that is very happy with her monovision contacts. She wanted a pair of glasses for when she wasn't wearing her contacts. She assumed they would be monovision just like her contacts. I told her I have never done that and we use progressives(or bifocals). I made her some progressives.

I ran into her at my doctor's office(she worked there)and she told me she was having problems with them. I was thinking that perhaps she might be happier with the monovision glasses and wanted to get others imput.

By the way, I wear monovision contacts with few problems. I do use my eye corrected for near at distance also. I just got back from Disney(fun!) and saw all the 3D movies just fine with the monovision contacts. If I closed the eye corrected for near I couldn't see 3D anymore.

 I think it is a widely held fallacy that people with monovision contacts don't have depth perception and don't use both their eyes togeather.

----------


## chip anderson

Happy:  Wait til you have a two or more add.  Then if you compare distance only with mono or bifocal with mono you will come to know about depth preception.  But it's still a bad idea and a horrible idea in spectacles.  And there is absolutely no reason to do this in spectacles.
Unless you have a really dense old blond who wants to say:  "I don't need bifocals, I just need one eye for near and one eye for distance."  
I don't know how many such women have told me: "I don't need bifocals I just have a pair of glasses for distance and another pair for near." 
What this accomplishes beyond possibly allowing them to think they are aging more slowly, I can't begin to imagine.
Or course you could use this as a ploy to keep the patient from realizing in spectacles what they are missing in mono-vision contacts by not having binocular vision.

Chip

----------


## orangezero

I'd agree with most that optically its a pretty bad decision.  However, I think there are some instances where it may be acceptable and even work better than progressives, bf, or tf.  Not too many, but there could always be exceptions.

I do have quite a few monovision contact patients that ask that question about monovision glasses.  I think for the vast majority of these patients bf or PALs are still the way to go.

----------


## LENNY

Acoording to our OD monovision does not work in glasses.
My experience is opposite. Isaw quite a few Myops that are way over 40 and for some reason were undercorected in one eye. 
Guess what were the results!
Monovison!
Tried to give them a full correction in both eyes and multifocals and some of them kicked my ...

----------


## Happylady

> Happy: Wait til you have a two or more add. Then if you compare distance only with mono or bifocal with mono you will come to know about depth preception. But it's still a bad idea and a horrible idea in spectacles. And there is absolutely no reason to do this in spectacles.
> Unless you have a really dense old blond who wants to say: "I don't need bifocals, I just need one eye for near and one eye for distance." 
> I don't know how many such women have told me: "I don't need bifocals I just have a pair of glasses for distance and another pair for near." 
> What this accomplishes beyond possibly allowing them to think they are aging more slowly, I can't begin to imagine.
> Or course you could use this as a ploy to keep the patient from realizing in spectacles what they are missing in mono-vision contacts by not having binocular vision.
> 
> Chip


My add is +2.25. I have binocular vision with my monovision. If I close my "reading" eye, everything looks flatter and lacks depth. I wear two distance contacts on rare occasions. Yes, the distance is slightly better, but I can't see anything up close. It's a trade off. 

Monovision is not perfect, but neither are progressive/bifocal glasses. There are flaws with each. I wear progressives, too, I know the good and bad of each. I don't think monvision contacts are a bad idea at all. They work very well for many people. I have tried bifocal and multifocal contacts and I still perfer my monovision. I have tried distance only contacts with reading glasses and I perfer my monovision contacts.

----------


## Ory

It is a fallacy that binocular vision is "gone" with monovision contacts.  Pick up a stereo test (fly, randot, etc) and you will likely see the gross stereopsis image in 3D but some of the fine targets (rings or animals) will appear flat.

Basically you are creating a central area of your field which does not have stereopsis.  The size of this area is affected by the disparity between the images.  Peripherally, where the visual acuity drops off a lot, your brain can merge the two images just fine.

----------


## AEOC

I've seen two patients with monovision glasses, neither of them wore contact lenses.  This seems to be more common in Asian countries, similar to myopic patients from the same area who prefer to be undercorrected.

----------


## fjpod

> I think it is a widely held fallacy that people with monovision contacts don't have depth perception and don't use both their eyes togeather.


Well said.

My wife, and several of my patients, have "natural monovision", i.e. they are plano in one eye and about -1.25 or so in the other.  They live normal lives not bumping into things.  These people are real happy well into their fifties.  In fact, if you try to correct the myopia in these people, they do nothing but complain.  There's nothing wrong with emulating this in contacts and to a lesser degree in spectacles.

----------


## ilanh

I routinely prescribe "monovision" distance glasses for any patient of mine who has had monovision lasik or is wearing monovision contact lenses.  Intially, the glasses were plano in the distance eye and about -2.00 in the near eye (the usual prescription for a presbyope). They would wear this mainly at night when they drove.  At times we would do it with transitions so that they could wear it during the day as well.  It works quite well except that after doing this hundreds of times I've learned to undercorrect the near eye by about 0.50 to 0.75.  For example, a 55 year old presbyope who actually needs -2.50 to see optimal distance in her reading eye would only get about -2.00 instead.

----------


## orangezero

> I routinely prescribe "monovision" distance glasses for any patient of mine who has had monovision lasik or is wearing monovision contact lenses.  Intially, the glasses were plano in the distance eye and about -2.00 in the near eye (the usual prescription for a presbyope). They would wear this mainly at night when they drove.  At times we would do it with transitions so that they could wear it during the day as well.  It works quite well except that after doing this hundreds of times I've learned to undercorrect the near eye by about 0.50 to 0.75.  For example, a 55 year old presbyope who actually needs -2.50 to see optimal distance in her reading eye would only get about -2.00 instead.


Let me see if I understand you correctly:  For the monovision lasik patient you have plano (or very close) in one eye and then the -2.00 in the other (instead of -2.50)?  Curious to know why you feel the need to lower it -0.50 to -0.75, especially if they are specifically for driving.  Difficult to adapt?  Patients still wanting some up close vision?  Just asking because I have more experience with monovision contact patients, and never had that problem, or havent' yet at least :)


Back on topic.  I did have a guy come in last week that was very adamant about having "monovision" glasses just like his contacts.  Turns out his contact was undercorrected by about -0.25, but it was hard to tell since he was a new patient.  New fitting put it more along the lines of -0.75 undercorrected and he want the exact same thing in his glasses, despite my five to ten minute discussion of all of his options and my recommendations.  Not sure what he ended up doing in the end.

----------


## Dave Nelson

I'm not sure why the undercorrection either, but it may be due to a small eikonic imbalance.

----------


## npdr

Are we talking about 2.50 diopter anisometropia or greater? Remember that for every 1.00D of anisometropia, that there will be aniseikonic problem of about 0.05 difference. . Thus at 2.50 there is already 1.50x. The eye and brain can tolerate about 1.6x difference before losing central fusion. T hen peripheral fusion locks are used. Ergo, loss of stereoacuity centrally but still probably able to do 400 seconds on the stereo fly. 

In addition, monovision works because of a loss of retinal rivalry. Retinal rivalry is hardwired. Therefore, a simple test can determine who will benefit and who will not. For those who show excessive retinal rivalry, no amount of lens power manipulation will change the outcome

----------


## rolandclaur

I have a couple of questions and hope you guys don't mind answering them.

1) Why wouldn't monovision glasses necessarily work.

2) If someone has perfect distance vision  and would have plano for distance power and an add for near,whatever the add power may be, would monovision work in this instance if there was one plano lens and one near add lens?

3) Does vertex distance play any significant role in the dynamics of fitting monovision glasses.

----------


## Dave Nelson

I often use "compensater" spectacles as well, primarily for night driving, but rarely over 1.5 D since I virtually never use more + than this on the contacts in the first place. I have also noticed, to my surprise, that some people who are completely occluded monocularly while looking through a phoroptor are often completely unaware of it.

----------


## orangezero

> I have a couple of questions and hope you guys don't mind answering them.
> 
> 1) Why wouldn't monovision glasses necessarily work.
> 
> 2) If someone has perfect distance vision  and would have plano for distance power and an add for near,whatever the add power may be, would monovision work in this instance if there was one plano lens and one near add lens?
> 
> 3) Does vertex distance play any significant role in the dynamics of fitting monovision glasses.


Depends on your definition of "work."  For an emmetrope (distance Rx plano OU) they will most likely subjectively notice a huge drop in binocularity and vision in the distance with a monovision spectacle Rx.  A lot just wouldn't like it...  Also, other options just work better in most cases.  Why not just Readers that they take off?  Why not BF or PAL if full time wear is needed?  Most often, these are much better choices and provide as close to optimal vision as possible for the patients particular needs.

Were you looking for something a little more specific or optically detailed?

NPDR is correct, if I remember its around 3D in diopter difference where the brain has difficulty with image size differences.

----------


## ilanh

Regarding why I undercorrect the "near eye" for distance:  I noticed after a while that even though post-lasik I was able to correct both eyes to 20/20 with monovision glasses, many patients confessed that they never wore their glasses when driving at night. These were very basic spectacles: essentially plano in the distance eye, -2.25 in the near eye with an AR coating.  When I questioned them further they admitted that the glasses caused them "strain or discomfort."  This is strange because those same people claim that they experience no strain with their 20/400 eye (their -2.25 near eye) driving at night.  I was baffled about this for a long time but was concerned about safety issues regarding monovision night driving.  Ultimately, I began undercorrecting the near eye such that their BCVA was about 20/40 (instead of 20/200-20/400).  This seems to have solved the problem for now.  I suspect that anisometropia may have been the issue or perhaps that lasik creates islets of multifocality on the cornea that does not respond well to a high powered myopic correction.

----------


## Dave Nelson

I still suspect an eikonic imbalance perhaps exacerbated by pupil size, since the specs are worn mainly at night. This could explain the complaints of discomfort. Reducing the rx may be effective if you are reducing it to the "comfort threshold," while removing the spectacles increases the disparity to the point of suppression.

----------


## gunner05

Actually, I fit mono-shooting glasses all the time. It's a little niche that I've found for myself in the area which no one else here really knows how to fit well. Pistol shooters have a hard time once presbyopia sets in and all of the local law enforcement officers know to come to me to get fixed up once they start having problems. It is always fun telling someone "well, you'll have to bring your gun with you when you see your OD so they can get the correct distance between your eye and front sight." Learn how to fit them, educate yourself on the varieties of tints used by competitive shooters (yellow, amber, red, G-15, etc) and you can set yourself apart from other opticals. I just hate that I'm restricted on my lenses for this since I work retail, but that's totally different.

The main problem that I've encountered is the induced prism due to the difference in Rx between eyes. For most people, it's not that bad, but some have problems that they can or can't adapt to.

----------


## fjpod

I think we are mixing a little apples and oranges here. (no pun intended, orangezero).  To me, monovision spectacles are not what you prescribe over monovision LASIK or CLs.  These are monovision compensating spectacles.  I prescribe them all the time.

In my mind, monovision spectacles are glasses that are prescribed where the non-dominant eye is corrected more for near.  Some patients come in asking for this, not because they have had LASIK or CLs, but because they just don't want multifocals.  I generally don't like to do this very much, because of greater problems with image disparity, vertex, etc.  Keep in mind though, plenty of people walk around with uncorrected anisometropia (like one eye plano, and one eye -1.25) and they are as happy as a lark.

----------


## npdr

> I often use "compensater" spectacles as well, primarily for night driving, but rarely over 1.5 D since I virtually never use more + than this on the contacts in the first place. I have also noticed, to my surprise, that some people who are completely occluded monocularly while looking through a phoroptor are often completely unaware of it.


Retinal rivalry.

----------


## npdr

> Regarding why I undercorrect the "near eye" for distance: I noticed after a while that even though post-lasik I was able to correct both eyes to 20/20 with monovision glasses, many patients confessed that they never wore their glasses when driving at night.'...


I think many ECP ("eye care providers") may prescribe best vision glasses whether anisometropic or not just to be self assured that the patient has best vision when operating a motor vehicle. In other words, a professional liability defense.

In reality anisometropic corrections are tricky. Anisometropic at the corneal surface is different at the spectacle plane (12-14mm away) Where a patient may tolerate anisometropic spectacles, they may tolerate it in contact lenses or in residual refractive outcomes. I believe or I suspect that correction image size dfferences for each eye are more critical than previously thought.

----------


## chip anderson

Back in the pre-implant days, we had many patients that while we could correct the aphakic eye to 20/20 we would have to under or over correct to 20/30+or- with contacts to prevent diplopia due to image size or ballance distortions in the spectacle corrected fellow eye spectacle.  

In a few other circumstances we could get the aphakic eye to 20/20 spectacle (due to magnification at macula) and only 20/30 contact.  We would usually feel that 20/30 with same in most excursions from center was much better than 20/20 central and all the distortions etc. peripherally in spectacles.

Still don't see a reason for monovision in spectacles except possibley for a unilateral aphake.  I do understand spectacles that bring the surgically or otherwise imballanced patient to best corrected va both near and far, butt then this isn't monovision glasses this is glasses to correct the problems of monovision.

Chip

----------


## sharon m./ aboc

Thanks to everyone that gave their input on this one.  We have a patient that is getting mono specs.  She is a first time presbyope that didn't like the progressives we made and can't wear contacts because Colorado has no humidty to speak of.  She wants lasik but can't decide if she wants to do mono lasik because she can't wear contacts.  Any how we tried a regular progressive and a short corridor progressive and she wouldn't even try to get used to them.  I used to work for an O.D. that said mono glasses don't work because of the vertex distance.  I don't think it's going to work and I think she needs a flat-top, but she's only 40 so she didn't want those either.  Oh well, if you can't get used to progressives with a +1.50 then you're probably not going to be able to get used to these either.  Right?   :Nerd:  
  Happylady,   What ever happened to your lady with the mono specs?

----------


## gunner05

Thought about a blended seg, maybe?  Just another option if this doesn't work out.

----------


## chip anderson

How about a plain old ordinary st bifocal.  One need not go high tech, high expense for a short term experiment with the odds against it in advance.

----------


## Happylady

> Happylady, What ever happened to your lady with the mono specs?


I fit her with progressives, not mono glasses. When I ran into her where she works she told me she was having trouble getting used to her glasses, but I think it is because she isn't wearing them very much. I told her she needs to wear them more to get used to them and to come and see us. I haven't seen her come in yet, though.

Keep us updated on your patient with the mono glasses. :)

----------


## macularry

HappyLady,

I will often do a spec Rx for my monovision patients over their contacts.  It usually comes up when they spend more than an hour continuously on the computer.  Monovision is great for casual use, but when someone sits at the computer for a significant amount of time, the imbalance can cause headaches and eye strain.  I like to trial fram the Rx in the office and let them sit at a computer.  They will love for the extra effort.

Most doctors don't like to take the time to compute the prescription.  I became tired of doing the calculation and I made a computer program that will do all the work for you.  You only have enter the person's age, height, computer monitor distance and their general use Rx and contact prescription.  It will even compensate for vertex distance.

If you would like to use it, shoot me an email:
DrLarryTarrant@aol.com

----------


## sharon m./ aboc

HAPPY "L''...................... Just as I suspected the lady with the mono specs (not over contacts) hated them... She's going to get lasik .  I think in both eyes and then she'll be strapped to reading glasses until the end of time.  I'd like to ask you something else.... I wear mono vision contacts and progressives and I think your rx is very similar to mine.  Since I wear my contacts most of the time when I wear my progressives I can't see as well out of the reading area in my "dominant" eye.  I wonder if you have the same  experience and if my brain is just so used to using that eye for distance only that the plus power just seems useless in progressives.   Anybody have any imput on this?

----------


## Jubilee

We actually have 3 patients who currently wear monvision glasses as backups to their contacts and love them that way.

----------


## drk

Interesting discussion. 

Group one: anisometropes
Group two: isometropes
Group three: monovision patients

Anisometropes more often than not do well with refractive imbalances because they "were born that way". They've _adapted_. As mentioned, a plano/ -1.25DS will be happy most the time uncorrected. A +1.00/+3.00 will be happy most of the time in +1.00 DS OU. What these folks don't do well with is FULL correction!

Isometropes, on the other hand, do not like to have _induced_ refractive imbalances, as a general rule. Looky, the monvision success rate is generous at 50&#37;, and that's factoring in all the minor +1.00 mono fits. 

The success rate is going to go way lower than that when you make the imbalance at the spectacle plane, with the resulting image size difference, and the _prismatic imbalance off-center_. Why do this when better alternatives exist?

Monovision patients are isometropes that have been iatrogenically turned into anisometropes. *They're a weird breed*. They can tolerate more than expected, because either their system is plastic, or we've plasticized it. Can they wear distance or near compensating specs? Oftentimes, but it's still difficult. I think Ilan is right: give as little plus or minus as you can.

So, to the original thought: monovision spectacles in lieu of multifocals?
Maybe, maybe, on adapted monovision patients, but again: *"Why"?*



*"...To boldly bold where no man has bolded before..."*

----------


## sharon m./ aboc

DRK< Yes, I've seen od's back-off a little on one eye...a half a diopter at the most but to make one a single vision lens and the other a distance lens. I don't see how anyone could walk around much less drive or take stairs. It is so disorienting. And I'll ask it again if you can't get used to progressives how do you get used to these?

----------


## sharon m./ aboc

> We actually have 3 patients who currently wear monvision glasses as backups to their contacts and love them that way.


When you say "backups to their contacts" do you mean 'over' their monovision contacts or 'instead of' their contacts? I guess it depends on the RX as well as the person. I don't see how anyone could benefit from the latter.

----------


## Jubilee

Yesterday I dispensed a pair of monovision glasses to be used as backups and her evening at home pair. We put her in progressives and in straight tops in the past, but last year she said she would rather have monovision in the glasses. We warned her of potential issues, but when she put them on, she thought they were better than any of the other types of multifocal correction we have done with her in the past.

We don't have very many of them, but I can name at least 2 others besides her that we have done this with.

Cassandra

----------


## sharon m./ aboc

WOW, It takes all kinds doesn't it?

----------


## Happylady

> HAPPY "L''...................... Just as I suspected the lady with the mono specs (not over contacts) hated them... She's going to get lasik . I think in both eyes and then she'll be strapped to reading glasses until the end of time. I'd like to ask you something else.... I wear mono vision contacts and progressives and I think your rx is very similar to mine. Since I wear my contacts most of the time when I wear my progressives I can't see as well out of the reading area in my "dominant" eye. I wonder if you have the same experience and if my brain is just so used to using that eye for distance only that the plus power just seems useless in progressives. Anybody have any imput on this?


I just got some new Definity Short progressives. My distance is -2.25 -.25 in both eyes with a +2.25. I don't notice any more problem reading through my right eye in my progressives then I do with my left eye.  Of course, I don't have any plus power in my glasses. The reading part is almost plano. I switch between my mono vision contacts and glasses easily.

I do wear a -.50 in my left contact so my close vision isn't quite as good as with my glasses(or without anything). Sometimes I use readers over them for extremely fine work.

----------

