I was recently told that I need surgery for cataracts. I've been told over the years that I have "natural monovision", and would like to go with monovision/mini-monovision with my IOLs. I have diabetic retinopathy, so it's going to be monofocus lenses (this doctor uses Alcon aspheric lenses, he didn't say what model.) My ideal situation would be able to see a range from reading (I read as close as 10-12") to distance of about 15-20 feet away, then wear glasses for distances/driving. Everything I've read seems to indicate that this isn't really feasible--near and far would be good, maybe or maybe not on intermediate, so I was hoping for monovision, backed off a little from optimum distance in my dominant eye to give me more intermediate vision, then after surgery and some healing decide on the second lens. Today I met the surgeon for the first time. He seemed kind of rushed, and said "our goal is to get rid of glasses."I corrected him, told him my ideal outcome would be to not need glasses for reading or up to about 15 feet, but didn't think that was an option. He said "we can do that!" He seemed none too happy about the monovision request, and said he didn't like to do it for people who haven't tried it (reasonable.) I'd brought in glasses prescriptions spanning several years, and he said "we'll give you what you've had." My glasses over the years have typically run -0.75 sph OD and occasionally up to -1.00 sph dominant RE (with a small astigmatism that comes and goes) with my LE ranging between -1.75 sph and 2.25 sph, again with a small astigmatism that comes and goes. (I'm not counting my last prescription, which was horrible.) So after the doctor said he'd give me back what I had, he said he'd be doing -1.00 for the RE and -1.75 for the LE.When I tried to ask him questions, he had to go, and said that their surgery coordination would be calling and would answer all my questions. My concern is that when I use -1,75 & -1 to calculate focal points, they only cover a range of about 57cm-1m (~22-39"). I've also read that depth of field is only about +/- .25-.5 D for monofocals, so best case my distance would only be about 2 meters (~6 feet) if I'm reading the charts correctly, and more likley to be in the 1.3 meter (~4 feet) range.I'm really worried that he's setting me up purely for intermediate and near vision and I'll be stuck in glasses for everything else. Plus it seems like I'll need glasses for near vision, too (I'm a voracious reader and have short arms.) I'm afraid I'll be left with good vision for the computer and not great vision for everything else. The other thing he said was that for monovision he needed to do laser surgery to hit the targets. If I have to pay the premium for the best vision, so be it, but I was a little surprised by it. Am I misinterpreting how the lenses work, or am I right to be concerned?
There is no easy answer. As you are probably aware everyone results will vary. You can start by looking at a defocus curve for the IOl you plan to get. That gives you the average results. Vision is complicated and remember you don’t necessarily need 20/20. So when you say you want to read at 10-12”, which is pretty close range are you expecting 20/20 at that distance? Is so you will need to shift that defocus curve a great deal to the myopic side, which then effects your distance vision.
Let’s start with some basic. The best clearest vision you can obtain IMHO is a monofocal combined with reading glasses.
You stated you want to try monovision and make it more myopic in the dominate eye. Hmmm!
I am going to give you my advice.
1)Find another surgeon. I did not like his responses.
2)If possible with your current vision try monovision with contacts and try different power levels,
3)Give serious consideration to the Light Adjustable Vision. Have you seen the videos on it. If not look on youtube. This lens is Amazing and you can adjust it postop to try different monovision setting. Not sure how many adjustments you can get, so you have to look into that.
I would bet you will not get what you want with that combination.
I recently got Eyhance lens with the dominate set for +.25 and the other set for -.25. My distance vision is outstanding and I would be 90% glasses free for my lifestyle (most of my reading is at an arms length computer) if I would have been set .5 closer vision. I’m 20/15 both eyes Snellen and would have still been 20/20 at that extra -.5 setting. When I put on my +.5 glasses my close clear focus is 23" and I can read signs just fine on the road. I loose a little distance sharpness as the close eye is then at -.75 and the distance eye is at -.25.
With no glasses on my near clear reading focus is at about 32" but not for fine food content print.
For your case, I put on my +1.5 reading glasses to see how that would line up with your -1.75 close vision eye. My really clear focus is 16" from that eye. You would focus farther away as a straight monofocal does not offer the small amount of EDOF the Eyhance offers. I also put on a pair of +1.25s and found my depth of field starts to defocus at 43" away and farther which would equal your distance eye of -1.
Since the straight monofocal is less flat in the defocus curve I would suspect you will not get what you want. See if you can get the Eyhance lens for as far as I can tell they are essentially monofocal + with no optical artifacts and they give you a little more intermediate when set for plano.
I must say the most difficult thing for me was switching from a lifelong nearsighted world where everything in the house did not require glasses (except when presbyopia set in) to a far sighted world. Having lived it for 3 months now however I would not trade it as I can do everything outside without glasses including driving night and day. The navigation screen on my car is very clear during the day and just a little fuzzy with street names at night. An extra .5 closer would have been perfect…but I already said that.
The .5 monovision I have does not seem to cause any problems and my contrast sensitivity is still good at night…even wearing the +.5 glasses. I might try a +.5 contact in a couple of months to see if I can tolerate more monovision.
I hope this gives everyone some real world numbers to work with. Everyone’s eyes are different and there is no guarantee the lens will end up at the expected settings. Pick a really good surgeon.
The thought with making the dominant eye a little myopic was to gain intermediate vision. Most of my activities are done in the near-intermediate range, with a fair amount up to around 15 feet. I have worn glasses primarily for driving; everything else I’ve gone without with my lovely built-in monovision. Now I’m wondering if a better approach is to get the near eye done first, see what intermediate vision I have, then get the dominant eye done. Too many variables, too many unknowns. If I have to get reading glasses to be comfortable, that’s the way it goes.
My optometrist actually referred me to another cataract surgery center first. I didn’t get past making the appointment with them. They were a meat market, and their approach was “we’ll pray over you prior to surgery” rather than offering to use the latest technology. Hey, if they want to pray, that’s fine, I’ll take help from any source, but when that’s the primary focus of their literature and web site it makes me a little nervous. Plus their staff was rude, and you never know what doctor you’ll see. Truly an assembly line.
It would be nice to try contacts for monovision, but I don’t think my vision now is good enough to have them work.
What threw my for a loop was talking about close vision at 10". I mean if you are talking 20/20 at 10" and just glancing at a defocus curve that means you are -4.0 d shifted and your vision would start to get really crappy really fast going further out. I mean even at 20" (2 diapoters out) your vision would start to not be all that good.
I really cannot relate or know the effect of such a decision.
If you are talking about reasonable monovision that is another story.
As I said before study the defocus curve for various IOLs and fully understand it and see what effect shooting for super close vision will have on overall vision.
In the end only you can decide what is best; if you want 10"-20" good vision and be legally blind at distance so be it. What can I say.
Sadly the way medicine is setup in the US it can be a meat market. But keep looking. I meet with several Opthalmologist before I went with the one I choose.
Look for a top Opthalmologist, one that participates in clinical trials, write papers and that you have a rapport with. If in the US, what state are you in?
If you are too high risk for a defractive IOL, maybe look at the Vivity IOL. Setting dominate eye to Plano and the other eye to -1.0 d. And wear reading classes to see Great at 10".
Read up on the Vivity and then schedule to meet with Ophthalmologist that have experience with that IOL. It is odd to me that some folks I meet, I am not talking about you, only go to the first Opthalmologist recommended to them. I personally want to meet several Opthalmologist and get their perspective and basically interviewing them for the job of implanting a lens in my eye.
One other piece of advice, the surgeon does not always hit the mark, so take that into consideration.
there is no guarantee the lens will end up at the expected settings
I cannot emphasize this enough. I have -2 monofocal lenses in both eyes (I prioritized near vision over far, since I’ve been a high myope most of my life and spend 80% of my day either reading or on the computer). My final outcome was -2 in my dominant RE and -2.50 in my LE. This has given me mini (micro?) monovision and I absolutely love it. I only need to wear glasses when I’m watching TV or when I leave the house.
However, the discrepancy could have been even greater, especially if I had targeted some sort of monovision in the first place, and I might not have adjusted well to it. In the end we are still flesh and blood (and vitreous), not machines where you can simply plug in a replacement part and know how it will work. Just something to bear in mind.
You don’t say how old you are or if you wear glasses all the time now. You don’t really have “natural monovision” if you wear glasses all the time to correct it. And if you’re under 50 it’s impossible for the surgeon to “give you what you had” because any accommodation you have left (natural ability to focus) will be lost after surgery. My personal feeling is that the setup you’re considering is highly unusual and you won’t be happy. I think you may be happier with both IOLs set to near vision and using glasses for TV and outside the house or with normal monovision (dominant set for 20/20 distance) plus glasses when needed. If you want a full range though you probably need a 2.5 D offset which is a very big offset and you absolutely must try that first with contacts. DO NOT do that big an offset surgically without trialling it. And bear in mind even that trial may not be 100% predictive if you still have accommodation.
I think you may be underestimating what a monofocal IOL can do. I have a monofocal Alcon AcrySof IQ lens in my right eye. The target was to leave me with -0.35 D required correction, or slightly myopic, and astigmatism was expected to be less than 0.4. As it turned out my spherical correction is 0.0 D, with -0.75 cylinder for astigmatism. I can see 20/20+ for distance and can see clearly down to about 18". I think to some degree the residual astigmatism is helping me get to get down to that 18" distance. If I had this lens in both eyes I guess I could use a computer with a very large screen and sit 18+" away. But more practically I would need readers. The most important thing the surgeon can do with a monofocal is to not go into the + or far sighted correction range. Much better to be -0.25 than to be +0.25.
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I would look at this as a process, rather than a single decision. The normal process is to do the distance eye first and target to be -0.25 D, but never into the + range. After the surgery and you find out what you really have, then you make the decision on the second eye. I currently am simulating monovision with the second eye by using a contact that leaves my under corrected by -1.25 D. I like it a lot. Computer work is not problem at all. If I had to work all day reading on my iPhone 8+ it would not be ideal, but for basic stuff it is no problem either. If your vision is good enough in your second eye, I would suggest using contacts to simulated monovision before you do the surgery and choose the under correction amount on the second eye. For me -1.25 D seems best.
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I don’t know of any reason to use laser surgery and both my eyes will be done with conventional methods. That said my astigmatism did increase with the surgery I had, so perhaps that is something that may be avoided with laser surgery. The incision for surgery can impact astigmatism, and the surgeon should chose to make it where the impact is minimized.
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As for intermediate vision, I find there is no “hole” were I don’t see well. For example I can see my car dash instruments with either eye perfectly. If there is a hole, it is at distance. With monovision you are only going to see really clearly with the distance eye, and for the most part the brain has to ignore the image from the near eye. That is why the dominate eye is normally picked for distance.
Dang it. I just about completed a long reply and then lost it.
After a day with a Defocus curve, Snellen and Jaeger charts, I’m feeling a lot better about things. Before looking at a defocus curve, the only numeric data I’d seen was that you only got “good” vision between +/- 0.25 D–which on this defocus curve equated to 20/20 vision. If 20/32 is acceptable (and I think it is at the distances at which it would occur) then the world becomes a better place. The Jaegar chart was really helpful–I compared the font sizes to that of some of my books, it would only take a correction of 20/50 for me to read them at a comfortable distance–and if I find I need some low power cheaters for smaller fonts, that’s ok. Looking at the ranges I’d have, the IOLs the doctor suggested (assuming he hit the targets and my eyes are near average) would not be bad. I’m going to run the numbers for lenses +/- 0.25-50 D from what the doctor suggested to see what would happen if the target is missed or if I feel some tweaking would be optimal for me.
As far as the age, etc–I’m in my early 60s. I’ve used glasses for driving for years, but other than for driving or things like occasional movies/concerts, I don’t wear them. I’ve been happy with having a “near eye” and a “far eye” and not wearing glasses. (I am old and fat. Glasses are hot and make my eyes itch.) I actually prefer wearing glasses to drive, because I like the air vents blowing on my face and the glasses keep my eyes from drying out. Plus I regularly wear sunglasses, so glasses outdoors aren’t a problem. I am a voracious reader and spend a fair amount of time on the computer. Spend a lot of time gardening, which is mostly intermediate-range work. (Although I wear an ancient pair of glasses that have almost zero correction to work in the yard to keep from getting poked in the eyes with sharp sticks.) I also cook–serious cooking–and have been frustrated by things like not being able to see clearly when cleaning up a piece of meat, or not being able to see bad spots on produce. Glasses fog up when you take the lid off a steaming pot and make you want to throw things.
As far as using Eyhance or Vivity or other premium lenses goes, they don’t sound like a good option given the poor health of my eyes. I can correct for distance with monfocals and glasses, but I can’t fix a reduction in contrast, which sounds like a potential problem. My doctor said he’d only consider monofocals given the condition of my eyes, and that was my feeling going in, so we’re in agreement on that one.
The doctor seems to be well respected, writes papers, etc. As far as the laser goes, he said that for monovision he uses it to better hit targets. If it assists his skills, it might be worth it.
Thank you all very much for your responses. They’ve been EXTREMELY helpful!
This is something I’m going to have to look at. I plan to use the defocus curve to figure out what vision ranges are predicted if the target was missed by up to -0.5 in either direction. Plus look at the degree of monovision in extreme cases. Depending on what I find out, I might ask the doctor to adjust which lens he uses. I think the doctor is not entirely comfortable going with monovision for someone who hasn’t “officially” experienced it with contacts so he’s proposed what seems to be a small amount vs what I’ve had historically. I took a bunch of old glasses prescriptions with me to the exam so that he could see my eyes are different enough for him to consider it. I haven’t worn glasses except to drive (and the occasional concert/movie type of event) and have let my eyes & brain handle what to do to give the best image. If I’m paying attention, and can feel which eye is working, and I’ll notice I’ve turned my head ever so slightly to give the working eye the best view. It’s been this way for probably 20 years or more; I’d never even heard of monovision until a few years ago when the doc mentioned that’s what’s going on. I just knew I had a near eye for reading and a far eye for distance, and it’s been great. The frustrating part for making an IOL decision is not knowing what’s attributable to the actual vision and what’s being done by the brain. I would guess the interpolation is better than extrapolation, but who knows? It’s pretty amazing what the brain can do regardless.
First off, I think you have been given good advice on going with monofocal aspheric lenses, considering the diabetic retinopathy that you have going on.
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On the powers being suggested, the surgeon is correct in that he is going to give you what you had when before cataracts and without glasses. I think it would work, but you would want to use glasses for sure for distance and driving. Even watching a larger screen TV would likely be compromised with those power of lenses. My thoughts are that you would be passing up an opportunity to be glasses free 95% of the time with that degree of under correction in both of the eyes. It would work for sure, but would not be ideal.
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To estimate what kind of visual acuity you would get you really need to be looking at Defocus Curves for the lenses. I am having to make a similar choice as you, and I have put together some defocus curves based on Alcon AcrySof IQ IOLs. They are not all that intuitive to read, but basically show visual acuity (vertical axis) vs defocus position in diopters (horizontal axis). “0” on the vertical axis is 20/20 vision, and above that is better than 20/20. Below that is a compromise from 20/20. I forget the exact correlation but -0.2 is considered good vision. But the important part is that the vision decreases gradually, and does not suddenly go to zero.
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See the graph below, and the table under it. The table is helpful to convert the defocus position to an actual distance. If the monofocal lens is corrected to 0 then you get slightly better than 20/20 . The dashed line is an estimate of what you get when you correct to -0.25. You still have better than 20/20 at the 0 defocus position. And you can slide the minus correction out to -0.5 D and still have 20/20 at distance (0 defocus). And you gain at closer reading positions. A -0.5 D would get you out to about -1.75 Defocus or 22 inches. If you have a little astigmatism, it may be even closer than that. If you visualize the curve instead sliding to the left, which would represent a miss on the surgeon’s you can see how you rapidly lose closer reading ability. That is why when making a choice on IOL power it is better to miss on the minus side, not positive. IOLs come in increments of 0.5 D so there will almost always be a decision between two lens powers.
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The green trace in this line is the -1.25 D under correction that I would suggest is more reasonable for the closer non dominant eye. It gives you an acceptable 0.2 vision acuity down to about -2.6 D which would be about 15". With that I would expect you could read normal 11 point test fairly easily. However to read the fine print on over the counter medications that they don’t want you to read, you could need readers.
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My thoughts would be considering that you can’t get a perfect correction due to the 0.5 D increments of IOL, would be to tell the surgeon you want the dominant distance eye to be between -0.25 to -0.5 D, and the near eye to be between -1.25 to -1.5 D under corrected. I think that would give you a better all around vision without glasses than the -1.0 D and -1.75 D that the surgeon is suggesting. And also have a discussion about which eye is your dominant eye. You want to do the dominant eye for distance and do it first.
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Hope that helps some. If you have questions about the defocus curves just ask. They are not the easiest to get your head around.
I posted a response, but for some reason it went into moderation. Keep checking back. It should be posted after moderation.
Note: Eyhance is a monofocal IOL
Thank you so much! This is really helpful.
I’ve seen some comments on Eyhance having problems with contrast if eyes are not at same target or if used with another kind of lens. Given my contrast problems now, I don’t want to use anything that could have negative affects.
I’ve decided it’s time to talk to another surgeon. I was able to access my records on line yesterday, and it makes me wonder if the doc and I were even in the same room. There was a lot of information he claimed to have covered (i.e. risks of surgery) that I KNOW he didn’t. What really burns me is that he claims all my questions were answered, when, as he rushed me out of the room, I showed him that I had a printed list of questions, and he told me the surgical coordinator could answer everything. He may end up being the best surgeon to use from a technical standpoint, but if I do use him, we’re going to have to have a looong discussion first.
Yes, in the US in Washington state. I’d love to use something like Vivity, but my Diabetic Retinopathy is limiting me to monofocals. I’m going to look into LALs, but I’m concerned about long-term stability.
Part of the problem I’m having is determining what visual acuity is acceptable. I’ve been doing a lot of hanging a Snellen chart on the back of the car, bushes in the yard, etc., and backing off until a particular line (20/30, e.g.) is the last one I can read, then seeing what things look like. Same with a Jaegar chart–I was surprised by what can be read with “bad” vision. (Reading No. 7 only takes 20/70? Really? That makes things better.) Using the defocus curve and making a lot of tables so I can sit down and evaluate ranges of vision.
If the odds were better that the surgeon would hit the target, the IOLs suggested would not be bad. BUT–and a really big but–I found a Review of Opthalmology article that referenced a 2018 study that found in close to 300,000 cases, only about 73% of the results ended up with errors within 0.5 D. ~93% within 1 D. I’m assuming that “within” equates to “plus or minus.” That’s a lot of potential error. Time to re-assess the plan.
Search this video in utube that just showed up. It has the logmar/defocus curve from a Spanish trial for both lens set plano …Plus1 EMV | RayOne EMV Early Outcomes Webinar with Dr Phillips Kirk Labor (USA).
It looks like the Eyhance is pretty flat for the the first diopter which is what I have experienced. I’m at .5 monovision as is and am going to try a +.75 contact in a couple of months to see if that is the optimum combination. I don’t experience any monovision adaptation problems at .5 now…I’ll see how the extra .75 is tolerated.
My +.5 readers are the icing on the cake for my lifestyle feeling comfortable for inside domestic muck about so it will be interesting to see how just having the non dominate eye corrected to -1 and the dominate one at the current uncorrected +.25 with the Eyhance lens works. I’ll step back and try a +.5 contact trial if the +.75 looses too much binocular vision or is uncomfortable.
Lasik or PRK would be an option then in the non dominant eye however I’m hesitant of all of the pitfalls I read about with those procedures. They might create as many problems as they solve. I have no halos or starbursts at night and would not want to give that up. No dry eyes problems either. Maybe the 3 years of taking C-60 has helped.
“I found a Review of Opthalmology article that referenced a 2018 study that found in close to 300,000 cases, only about 73% of the results ended up with errors within 0.5 D. ~93% within 1 D. I’m assuming that “within” equates to “plus or minus.” That’s a lot of potential error.”
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That is one of the reasons why it is always best to do one eye at a time and wait 6 weeks before doing the second eye. You then know what you have. If you do the distance eye first and the surgeon misses on the under correction side, then you can consider doing the second eye for distance and use the first eye for closer up. It is not ideal to do the non dominant eye for distance, but it can be done – called crossed monovision. That is what I am currently simulating and will be what I end up with when I go ahead with the second IOL for closer up.
I’m almost certain you’re thinking of Vivity not Eyhance. Vivity does have very low contrast in the MTF50 bench test due to it’s heavy reliance on high order abberation optics and because of that I would not recommend any offset with Vivity (although surgeons are doing it… slightly). J&J Eyhance does not suffer any contrast issues. The Eyhance contrast profile is almost identical to the the J&J Tecnis 1 monofocal. In bench testing it’s contrast is double that of Vivity and at 5mm apature it’s contrast is actually 30% BETTER than even Alcon’s monofocal IOL. And again Eyhance is technically sold as a monofocal. It just has a little more central power for a little more intermediate. But it’s a perfectly smooth lens like a traditional monofocal (and unlike Vivity with it’s 2 raised areas). I think it’s a great option for almost anyone who’s considering a traditional monofocal aside from the most demanding patients like airline pilots that need every single bit of distance quality they can get where even a very tiny quality difference would matter.