Mini-monovision with Eyahnce and RayOne EMV

Thanks Indy for the reply!

Do you experience any side effects like halos and glare with Rayner EMV lens?

Oscar,

I have no halo or glare issues. I'm not sure what RonAKA is talking about when he says the Rayner EMV lens is just like any plain monofocal lens. It does act much like a monofocal lens (no dysphotopsias for example) but my understanding is that there is positive spherical aberration built into it which gives an enhanced range of vision. The reason I chose it is because the offset required to gain functional reading vision was less than what is required from a standard monofocal, leading to better stereopsis. As I've mentioned my surgeon abandoned Eyhance and prefers the Rayner EMV over it. I'm very happy with my results.

Indy G

RonAKA,

I'd be interested in the source you're utilising to come to the conclusion that the Rayner EMV lens is "just a plain old monofocal" lens. I would be quite surprised that a doctor of Barrett's stature would put his name behind something so misleading as you're suggesting. With a 70% rate of acquired reading vision with both eyes targeted at emmetropia suggests a range of focus larger than a typical monofocal. I'm open minded to considering your opinion, but I also think it's highly unlikely my surgeon would abandon the Eyhance lens (which he had used previously) in favour of the Rayner EMV unless there was a compelling reason to do so.

Indy G

Have a look at this report, and in particular Figure 2. It shows the defocus curves for some monofocal lenses plus the Eyhance ICB00. The Rayner lenses are shown at 0.0 and -1.0 D, a monovision configuration. The RayOne at 0.0 D is insignificantly better than the standard Tecnis 1 monofocal, ZCB00. You can see that the Eyhance has much better depth of focus than the RayOne and ZCB00.

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Laboratory Investigation of Preclinical Visual-Quality Metrics and Halo-Size in Enhanced Monofocal Intraocular Lenses Grzegorz Łabuz, Hyeck-Soo Son, Tadas Naujokaitis, Timur M. Yildirim, Ramin Khoramnia & Gerd U. Auffarth

Hi RonAKA,

From what I read of that study you posted it says the following: "An optical-metrology station was used in the assessment of IOLs' optical quality in polychromatic light.". I'm not sure exactly what an optical metrology station is but it seems to be machine-measured based and not based on patient experiences. From what I understand, when positive spherical aberration is introduced into a lens (as the Rayner lens is designed to do) the light rays form more of a small "disk" of light than a more "pinpoint" of light as a monofocal is designed to do. Although this creates a more diffuse light beam hitting the retina, the brain for the most part ignores the fainter image (because it's so subtle) yet the subject gains more depth of focus as a result. Whilst the study you point out mentions they used a monovision scenario for the Rayner lens, I still don't see how Rayner has misled anyone in their marketing materials. Check out the following video on YouTube (I don't know if I can post the actual link so I'll just give the search term). Search YouTube: "WEBINAR: RayOne EMV: A monofocal IOL providing extended range of vision to patients". Clearly Dr. Barsam is making a point that, in practice, the lens has depth of focus benefits over a standard monofocal. I hope this helps.

Indy G

Yes it is well known that correcting spherical aberration, partially correcting it, leaving it uncorrected, or even using a spherical non aspheric lens will impact the depth of focus. See this B+L graph showing the effect along with a comparison of the Tecnics 1 (full correction), AcrySof IQ (partial correction), and B+L enVista (neutral correction). Not shown would be the old spherical non aspheric lens that is not used much any longer. It would come in at about +0.37 SA, and provide even more depth of focus than the enVista.

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Now if you look at the Figure 2 from the link detail I gave you. Put Springer into the very beginning of the search for this phrase and you will get a more detailed report than the pubmed version. Here it is:

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As you can see there is very little difference between the RayOne 0 D curve and the Tecnis 1 curve. The RayOne is a touch better than the fully asphericity corrected Tecnis 1, but I would suggest it is insignificant compared to the EDOF provided by the Eyhance. The IsoPure is better, and the AE2UV/ZOE is very close to the Eyhance. I am not sure where the enVista would place compared to the RayOne, but I suspect it may be significantly better. The enVista is a standard monofocal offering at no cost in some provinces in Canada.

Hi Ron,

Thanks for that info. I think I was reading the wrong graph earlier but I can see from Figure 2, that the defocus curves of the Tecnis and Rayone are very similar in that study. So how do we explain then the following article (I've put a space in between dot and com) where the Rayner lens is indicated as having an extended depth of focus. www(dot)review of ophthalmology. com/article/an-update-on-monofocalplus-iols, or to the study referenced in Rayner's materials showing an elongated, less sloped defocus curve than the Eyhance lens, or the myriad surgeons (and Barrett himself) who are touting the Rayner lens as anything but a standard monofocal? I honestly don't think all these guys (and Rayner itself) would risk their reputations on a conspiracy of an apples to oranges comparison of the EMV to other EDOF lenses (i.e. comparison of monovision to a normal single lens scenario). There are too many compelling reasons not to. First, Rayner has to pass the government regulations hurdles, FDA approvals, etc. Second, they need to win over the hundreds or thousands of opthalmologists/surgeons across the globe to adopt the lens into their practices. It would make no sense for Rayner, an already very established player in the field, to make claims about a lens that it doesn't deliver on. All I can say from first hand experience is that I'm very happy with the Rayner EMV lens. I'm reading J1 sized print (20/20) and seeing 20/30 distance with a 0.75D offset. I'm getting far more binocular summation, less suppression, than when I had my natural lens with a 2.00D offset. I imagine there are people that may have varying results depending on their unique circumstances, eye shape, etc.

Cheers,

Indy G

That Review of Ophthalmology article like much of the Rayner sales info is very misleading. They talk like it is one lens, when in fact it is two lenses; one at plano, and one at -1.0 D. The extended depth of focus comes almost entirely from the monovision configuration, not from the lens design itself. See this key point in the article:

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"This monofocal lens offers up to 2.25 D (with 1-D offset) of extended depth of focus."

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In other words you need two of these lenses in a standard mini-monovison configuration to get this depth of focus. And you could get basically the same thing with two Tecnis 1, Clareon, or B+L enVista monofocals in a -1.0 D offset configuration.

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"the study referenced in Rayner's materials showing an elongated, less sloped defocus curve than the Eyhance lens"

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Keep in mind this "elongated, less sloped defocus curve" is when the RayOne EMV is used in a mini-monovision configuration. This less sloped effect is due to monovision configuration and very slightly due to the non asphericity correcting lens design. Unlike the RayOne EMV, the Eyhance is achieving the extended slope from the lens design itself.

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I think it is good that Rayner (and Barrett behind the scenes) are promoting mini-monovision as a good solution compared to multifocal lenses. But this solution does not require the EMV lens. The B+L enVista is likely just as good or perhaps better.

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To get back to the original question asked by @oscar11025 I would recommend the Eyhance over the RayOne EMV lens. As you can see in that figure 2 I posted earlier, the Eyhance in a one lens configuration has a much more gradual slope than the RayOne EMV. The Eyhance in a -0.75 D near eye configuration would most likely provide better close and intermediate vision as well as better distance vision than the RayOne at -1.0 D.

Hi Ron and Indy,

I've always understood that the Rayone EMV provides a 1.5D depth of vision per IOL and a total of 2.25D depth of vision when the second IOL is implanted within an offset of -0.75D. The other advantage is that their MTF is shifted to the right and the peak isn't at 0D when plano is targeted. I believe that it would provide a good depth of vision and it has also a rigid structure that makes me considering it for myself.

The only concern I've is the MTF curve at 4.5mm aperature for the lens implanted at plano and at -0.75D offset. Rayone EMV looses performance dramatically with larger Pupils, and this raises my concerns that it would provide low contrast sensitivity and low vision quality at night or low light conditions. Also it's clear from the MTF curve that the vision quality of EMV at distance is lower than Eyhance. I am not able to quantify the concussion to the vision quality to understand whether its an acceptable trade off or not to the depth of vision it provides.

Indy, what's your experience in the EMV eye in very low light conditions?

BR,

Will

Hi Ron,

In the Rayner meterials they state emmotropic targeting ("best distance vision"), not a monovision scenario.

Then there's this:

--RayOne EMV is the only patented aspheric IOL that induces controlled positive spherical aberration.

Compared to a lens with zero spherical aberration, the carefully controlled positive spherical aberration induced by RayOne EMV spreads light along the visual axis, elongating the focal range from far into intermediate with over 1.5 D of depth of focus (per lens on the spectacle plane).

Below shows an illustration of a lens with zero aberration and a small focal range (Figure 1), shown together with RayOne EMV with positive spherical aberration and a larger focal range (Figure 2).--

Note,"Per lens" above, not a monovision scenario. Even when targeting emmetropia, the Rayner lens virtually guarantees intermediate vision, something standard monofocals don't. And the lens often achieves functional reading vision in 30%-70% of cases.

I imagine Oscar will be happy with either choice and, as always, there will never be a way of knowing for sure which option would give him the better outcome. Certainly the Eyhance lens is more popular in the US as its been out longer, earlier approval, etc. All I know is my surgeon abandoned it because he felt the Rayner EMV was giving him better results.

I recommend Oscar do as much research as he can and get comfortable with his and his surgeon's choice. After all, we are not professionals.

Cheers,

Indy G

Sorry, but my conclusion after looking at the Eyhance and RayOne lens is that there is no comparison in the extension of depth of focus. The RayOne may provide a very slight (0.1 D) of extension over a -0.27 SA aspherical lens like the Tecnis 1, but it is not even in the same ballpark compared to the Eyhance. I suspect the extension of the RayOne compared to the basic B+L enVista will be even smaller to the point of being negligible, compared to other factors. I looked pretty hard to find how much positive spherical aberration is achieved with this RayOne lens, but could not find it. They seem to keep it a secret, and only say it is positive. Many older design spherical lenses have positive spherical aberration in the range of 0.1 SA. They have been around for many years.

My suggestion would be to research the B+L enVista if you want a lens that is more forgiving and has a small extra depth of focus without sacrificing significant contrast sensitivity. Instead to reducing SA to zero like the Tecnis 1 does with the -0.27 SA built into the lens, the enVista is neutral and does not correct any SA in your eye. Typically this leave you at about +.27 SA. This is likely a good compromise between contrast sensitivity preservation and distance acuity vs depth of focus. It is less sensitive to being off center in the eye compared to SA correcting lenses. You may also find that the B+L enVista is more available and at lower cost. For min-monovision a good target is -1.25 to -1.5 D in the non dominant eye on a spherical equivalent basis.

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For a hybrid monovision solution, a Tecnis 1 in the dominant eye set to plano and a Eyhance at -1.0 to -1.25 D in the non dominant eye should work well too. The Tecnis 1 should give you good distance visual acuity along with maximum contrast sensitivity, while the Eyhance will give good close vision and intermediate vision. In the Alcon world, a Clareon at plano in dominant eye, and Vivity at -0.75 to -1.0 D should work. But as the Vivity stretches EDOF more the risk is elevated for optical side effects.

Hi Wiley,

Thank you for your comments and question. I agree with you on your interpretation of the Rayner lens in terms of depth of focus both individually and in a mini-monovision setting. Now, it does seem there are differing defocus curves floating around out there when comparing the Rayner EMV to Eyhance. In the Rayner literature, they show both a more flattened curve to the negative side further out as well as a "hyperopic bump" where, in theory, you're getting more distance vision than the Eyhance. The "sacrifice" in the Rayner lens appears to be in the first diopter "in" where apparently the Eyhance wins out. As we know, there's no "free lunch" with optical light and thus it's all about how the light is allocated.

Now in my own experience 2 months in with the Rayner EMV lens (standard, not toric) I can honestly say I neither feel handicapped in any way from a low light vision perspective nor from a dysphotopsia perspective nor from a visual acuity perspective. Bear in mind I had a Zeiss monofocal lens (implanted 4 years ago) in my "distance" eye and my Rayner lens is set -0.75D from that. Because both eyes overlap in focus at intermediate range, I like to play my vision off each eye by closing one then the other and observing the differences, if any. For what it's worth, when I do this I'm rather surprised to see that the Rayner eye is somewhat brighter, more vibrant. It's not by much, but it's detectable. Maybe because the lens is newer? I don't know. In any case, I feel blessed we live in these times where technology basically solves vision affected by cataracts. I feel I have the vision of my 12 year old self long ago. If I could go back in time I would perhaps put the Rayner in my distance eye as well to eek out a bit of extra near vision (via the extra depth of focus) but it's a very minor matter. I'm essentially spectacle free for everything except perhaps endurance small print reading. At near arms length to computer distance where focus converges in both eyes I'm absolutely fine. I hope this helps.

Indy G

I will repeat again that the reason for the discrepancy in the defocus curves comparing the RayOne EMV to the Tecnis Eyhance is because the RayOne EMV is a Raynor patented use of their lens in a binocular mini-monovison configuration. I find their document which you can find with the search terms below to be very misleading. While they say they are comparing the Eyhance in a binocular configuration to the RayOne EMV in a binocular configuration, the monovision configuration for the RayOne is not included in this paper, which I find deceptive. However, in other news releases they say:

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"RayOne EMV extends a patient’s range of vision with a patented non-diffractive aspheric optic profile, designed to: Provide up to 2.25 D of extended depth of vision (with 1.0 D offset)..."

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Raynor RayOne EMV White Paper PDF

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This White Paper is a very unfair comparison of the two lenses. If they wanted a fair comparison they should have offset the Eyhance lens by the same amount as the RayOne EMV was offset. This would have shown that the Eyhance with the same offset would result in a far superior range of depth of focus.

Ron,

But in the materials I've read that compare the Eyhance to the Rayner EMV defocus curves it states as follows: "Bilateral emmetropia was targeted for all patients in both groups. ". They're not comparing apples to oranges there. I don't know how that can be taken as comparing a Rayner monovision strategy with a set distance lens Eyhance. Rayner's materials also show graphically how the lens outperforms (in terms of depth of focus) standard monofocals again set at emmetropia with images of the focus zone hitting a drawing of a computer screen, again set at emmetropia.

I urge anyone reading this to consult the Rayner PDF's and draw their own conclusions. In my mind, anyway, I have not been convinced of any sort of misleading adverts or conspiracy here.

Regards,

Indy G

I have found that sometimes one can get good technical and non bias information on these lenses from the FDA approval process. For example if you search for FDA Vivity Package Insert PDF, you will find good information on how the Vivity lens defocus curves etc compare to their standard monofocal.

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I tried that with the RayOne EMV but did not find much. It appears that Raynor has not submitted any clinical trial data to show there is any extended depth of focus achieved with the lens. They have submitted some theoretical data which suggests there may be a slight amount, and said that it is up to surgeons to determine the benefits and risks for themselves.

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If you search for this phrase you should find the only document that I could find.

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RayOne-EMV-IFU-USA-PF000142-02 pdf

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Some quotes from it:

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"All IOL optical designs are associated with a certain amount of depth of focus. For

monofocal IOLs, the amount of depth of focus is typically limited. The The EMV IOL

uses an optical modification of the IOL surface to have an aspheric profile that adds

positive spherical aberration (Figures 3 & 4) that is designed to slightly extend the

depth of focus as measured in bench testing compared to the parent monofocal

Aspheric IOL (600C) (Figure 4). The positive spherical aberration of the EMV lens

smoothly transitions to negative spherical aberration towards the edge of the optic

to help control the total spherical aberration at larger pupil sizes. (See Warning

#1. for advisory on patients with large pupil sizes). However, clinically meaningful

extension of depth of focus has not been demonstrated in clinical trials . In general, extending the depth of focus negatively affects the quality of vision. Vision quality can be estimated using non-clinical testing (Figures 3-5)....

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Warnings:

1. Patient with large pupils (> 5 mm) may

   not be suitable candidates for this

   intraocular lens. Although this lens has

   not been studied clinically, its optical

   design is expected to be associated

   with increased risk for subjective

   visual disturbances (glare, halo, etc.),

   as well as increased risk for the

   reduction of visual acuity and retinal

   image quality in patients under large

   pupil conditions, as well as in the event

   of lens decentration."

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   They do not include defocus curves in this information but do include an MTF curve (figure 4), which if you expand it up to 300% or so you can see a comparison of the EMV 200E lens to the standard 600C lens. The MTF is reduced at peak focus with the EMV lens, and has a very slight improvement in the -1.0 to -1.25 D range. In the scheme of things this improvement does not seem very significant to me. In general LogMAR visual acuity tends to track with MTF. This slight improvement seems to be in the same order of magnitude as was reported in that paper where they measured the visual acuity of the various lenses and found that the EMV was slightly better than the Tecnis 1.

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   This still leaves me searching for credible information that shows the EMV has a significant extension of depth of focus on a single lens basis. Keep in mind when reading Raynor material that EMV is short for Enhanced Monofocal Vision. They have patented the use of their lens in a monofocal configuration. I am not aware of anyone else doing that, and it would make sense for them to use a monofocal configuration when comparing their lens to others. That is what they patented - but on a quick search I cannot find their patent details. It would be an interesting read if one could find it.

I must say, as I have said before, that some of the regular members of this forum are extremely well-informed about the technical aspects of IOLs and optical physics, and probably know as much about those topics as most optometrists and ophthalmologists . People who come to this forum to seek information are fortunate to have members like Ron and others who generously give of their time and knowledge to them to become well-informed patients. I thank them for what they do.

It's fairly early days for the Rayner EMV, particularly in the US so, yes, data is still coming in. But still the experiences and statements from many high profile surgeons is promising. I want to step back for a moment to shed clarity on the interpretation of the Rayner vs Eyhance defocus curves. I found this video (search: "Early outcomes webinar with Dr Phillips Kirk Labor"). At 7 minutes 30 seconds into the video the Rayner representative clearly explains the curves as being like for like ( i. e. No monovision offset). He makes a point to express this explicitly. I hope this clarifies any confusion on at least this particular point.

Regards,

Indy G

I reviewed that video and captured this screen shot at the 6:32 point.

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This is a bit of an unusual way to display the MTF curve with the peak set at 22 D instead of at the 0.00 point of emmetropia used for standard defocus curves. But in any case the relative comparison should be valid. For reasons that are not explained in the video they have chosen to display the EMV curve displaced off to the right by about 0.75 D, instead of at 22 D like their standard aspherical monofocal and the Eyhance. Seems strange to do that. However if one mentally moves that brown EMV curve to the left so it peaks at 22 D to make it comparable to the other two, I would suggest the drop off to the right side is just as steep as the standard lens and inferior to the Eyhance. This is consistent with the MTF curve in that FDA document, and to the other study I referenced which showed the EMV to be virtually identical to the Tecnis 1. I will have to look at the left hand side of those reports again to see if I can see the more gradual hyperopic curve or not.

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I noticed that the Barrett video advocates using this lens with monovison, and not bilateral emmetropia. Then there is this Spanish surgeon material, which the data from which they say they have on file, but there is no reference to a formal study or report. This is the curve I take issue with as it is inconsistent with those other two references and is even inconsistent with their own curves in this screenshot. That makes me remain skeptical of this claimed bilateral emmetropia defocus curve. It looks much more like a monovison configuration. Perhaps at some point Raynor will come out with clinical trial data submitted to the FDA for approval. Right now they don't seem to have it.

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If this screenshot is accurate then their claims to have a smoother transition between the lenses in a monofocal configuration would have some merit. It does not justify the claim that the EMV provides more depth of focus than the Eyhance though.

Thank you Ron and Indy for the constructive discussion, this is really helpful for many folks like me.

While my previous post is being moderated. I will make this additional one. I remain concerned that the data provide from the M. Royo, Spanish study is misleading, and the details of it are undisclosed. On a search for it, I found this article instead, which is much more informative in the compaison of the RayOne EMV and the Tecnis Eyhance. Use this to search for it:

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Helio PDF Visual Acuity, Wavefront Aberrations, and Defocus Curves With an Enhanced Monofocal and a Monofocal Intraocular Lens: A Prospective, Randomized Study Mayank A. Nanavaty, MBBS, DO, PhD; Zahra Ashena, MD; Sean Gallagher, BMedSci; Steven Borkum, DipOptom (SA); Paul Frattaroli, MA (Hons), MA (Post-Grad); Emma Barbon, BSc

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The most useful graphs are the standard defocus curves shown at the top of document page 16 (PDF page 7). They clearly show that the Eyhance has a wider depth of focus when implanted both uniocular and binocularly. These graphs make sense based on the other independent data available. They are very different that the M. Royo data. Further these curves do not show the hyperopic bump to the left of emmetropia that Raynor claims the lens to have. If anything the Eyhance is flatter. Conclusion of the study:

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"CONCLUSIONS: The TECNIS Eyhance IOL provided better

DCIVA and broader defocus curves than the RayOne IOL. There

was no difference in CDVA or patient-reported outcomes. Although there were some differences in aberrations when measured with normal pupil size, they were not clinically significant."

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Based on this information, I would choose the Eyhance over the RayOne EMV for a close eye monofocal solution. If the same offset was used for both lenses the Eyhance would provide better close vision and essentially the same distance vision. If the RayOne was offset by perhaps 0.25 D more than the Eyhance it would provide similar close vision, but the Eyhance would provide better distance vision as it would be offset less. And I think if one has the opportunity the best overall solution would be to use the Tecnis 1 aspheric lens in the distance eye, and the Eyhance in the close eye.

Suggest you wait to see the posts that are currently being moderated before making any decision. Short story is that I would choose the Eyhance over the RayOne EMV for the close eye in a mini monovision configuration.

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EDIT: I just realized I was duped again by Raynor. That last study I gave reference to is comparing the Eyhance to the RayOne Aspheric lens which is different than the RayOne EMV it seems. So there still is no detailed data showing the EMV version is actually better than the standard aspheric one.

Oscar,

You're welcome. If I were you I'd spend a few hours or a day doing more research on both the Rayner EMV and the Eyhance lenses. I think either one is potentially suitable. Ultimately, it's going to be your decision with, I expect, major weight given to your surgeon's recommendation. If he/she isn't familiar or experienced with the Rayner EMV lens then that will likely disqualify that option anyway. But if he/she IS familiar and experienced with the lens, then certainly he/she can give you a more informed assessment than I ever could. I personally went with the Rayner lens because I trusted my surgeon, had confidence in the co-developer of the lens Graham Barrett, and the underlying concept of positive spherical aberration enhancement seemed to make sense to me.

Good luck to you. Let us know how it goes with your surgeon.

Cheers,

Indy G

You've stated, "For reasons not explained in the video they have chosen to display the EMV curve displaced off to the right by about 0.75 D.". But HE HAS explained that. He states that the highest MTF values ought not be the main objective of an IOL and that some sacrifice can be made to that metric (as we know the Vivity clearly does, and a rather large sacrifice at that) ) in the pursuit of not only greater myopic range but hyperopic range as well. THAT'S why the Rayner EMV lens works optimally in a mono-vision strategy. The lens offers a bit of "hyperopic shift" in the "near" eye that allows more stereopsis (binocular vision). Indeed, it seems to be that a surgeon can err to slightly negative (say, -0.25 to perhaps -0.50) with this lens, in the distance eye, and have the patient still wind up with excellent distance vision.

There are no inconsistencies in my view in regards to the various graphs given their explanations. As the Rayner rep said, "Modulation transfer functions are great but I think even better are real world defocus curves". So the MTF curves, while useful to a point are not necessarily indicative 100% to real world experiences. Yes, I agree there is still data coming in, larger studies to be done, but increasingly surgeons (particularlyin Europe/UK) who have tried the Rayner lens have shifted to using it as their "go to" lens.

There is no free lunch with the Rayner EMV, or any other lens for that matter. It's mainly about how the lens is designed to use the light and how they get there. In the EMV case they get there using positive spherical aberration and perhaps some other lens design element and they spread the light according to where they feel it's most useful.

Indy G

The reason they are stating that MTF (contrast sensitivity) "ought not to be the main objective" is that all of these non pure monofocal aspheric lenses compromise the MTF to obtain more depth of focus. Some compromise it more and some less. But, that has nothing to do with the reason for the EMV being displayed off to the right and without the peak at the 22 D position. To be frank, I think they did it so viewers could not easily compare the shape of the curve of the EMV to the standard aspheric lens. To my eye, if you move the EMV curve back to the left it is not going to have any more range of focus than the standard lens, and less than the Eyhance lens. This strikes me as being deceptive.

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"Modulation transfer functions are great but I think even better are real world defocus curves". I agree 100%, and the basic problem is that Raynor does not seem to have conducted well document clinical trials to produce credible defocus curves. All they have is that Spanish surgeon's data which has not been provided for review. The shape of that curve looks very suspicious and is not consistent other available data like MTF curves, and lab measured defocus.

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Raynor claims and my thoughts on them:

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Use of Positive SA to extend the myopic depth of focus - This may very well work to a fairly minor degree, but they have not provided the data to back up the claim. They only provide it in the middle of the lens and the positive SA transitions to negative at the edge. The issue with this is that the lens can be sensitive to decentralization, and the positive SA is lost as the pupil opens up in dimmer light. Probably not an issue for an older person, but could be for a younger person with a pupil size of 5 mm or more. Could also give rise to halos with a larger pupil size.

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Use of Positive SA to extend the hyperopic depth of focus. The screenshot from the presentation shows that to be very significant. However, based on the MTF curves it is not that significant and is pushed out quite a way into the hyperopic zone, but it does show up. This effect is mainly the one that Barrett refers to as a benefit in the near eye of a mini-monofocal configuration. This improves the distance vision in the near eye, and the ability to get some vision from both eyes instead of one. This effect seems unique to this particular lens and is a good idea. I don't know of any other lens opimized for monovision like this. However, I am not so sure it is significant enough to be of a big benefit. Accurate clinical trial data on the defocus curves would be of value in determining if it really works or not. This hyperopic effect is of value in the near eye, but provides no benefit in the distance eye.

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The bottom line is that Raynor are making some nice claims about this lens, but do not seem to have the FDA quality clinical study data to back them up. On the other hand there is lots of data on the Eyhance. Of the two choices, I think the Eyhance is the safer bet for the close eye in monovision.

Hi Indy,

Thanks for discussing your Rayner EMV experience here. I've been researching IOLs and have watched a lot of videos discussing both the Eyhance and the Rayner lenses. But it really helps to get insight from people who've actually had the lenses implanted.

A few questions, if you don't mind. You say you read J1 print with one eye plano and the other with a 0.75 offset. At what sort of distance would that be? I believe near vision testing is usually done at around 40cm/16 inches; can you read J1 sized print at that distance? That would be amazing. Or is the J1 at an intermediate distance? At what near distance does your vision start to blur? Do you feel comfortable reading a book or do you use readers for that kind of close work?

And for your intermediate vision, is the vision crisp, and does it seem "natural"? I guess what I mean is, since you're using a mini-monovision setup, does the blended vision feel as natural as if your were using glasses set to give normal intermediate vision? Can you use a computer comfortably for an extended period of time?

And lastly, with distance vision of 20/30, would you feel comfortable driving a car, or just going through your day, without any kind of additional lenses? Do you have an additional pair of glasses to "sharpen up" your distance vision, for situations where you feel you want things really clear? Right now, my corrected glasses vision is 20/20, so I'm not exactly certain what 20/30 vision is like.

Also, I enjoy amateur astronomy (or used to, before my cataracts began to make that difficult), so having vision that is correctable to 20/20 (or even better, if possible) is pretty important to me. It's also why I've rejected multi-focal iols in favor of monofocal, to avoid, as much as possible, the prospect of dysphotopsias, like halos or glare.

Sorry for all the questions, but like most folks who post here, I'm trying to get a real feel for how vision with iols might be, especially using mini-monovision.

Thanks,

Brad

Brad, I do not have the Rayone EMV lens, but I do have mini-monovision with pure monofocal lenses. I will leave the RayOne EMV personal experience comments to those that have it. On a spherical equivalent basis my distance eye is -0.25 D, and my close eye is -1.40 D. The distance eye has an Alcon AcrySof IQ Aspheric lens, while the close eye has an Alcon Clareon Aspheric lens. Both are pure monofocal lenses with a -0.20 um SA correction built into the lens. At the optometrist office I can easily see 20/20 and perhaps half of the 20/15 line with my right eye, or both eyes. It doesn't make much difference, but my distance eye is doing the lions share of the contribution. At the standard Jaeger chart distance of 14" I can easily read the J1 line in bright sunlight, and vision starts to jam out at about 10-12". This of course is with my closer eye. My distance eye starts to become useable at about 18-20" and my visibility of my car dash is very good with both the distance eye and close eye. I have irregular astigmatism in my close eye, and to some degree that limits my near vision. But, all in all I almost never wear my prescription progressives, and occasionally use +1.25 readers for very fine text in dimmer light conditions.

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If your overall objective is to have the best possible visual acuity for astronomy I would suggest getting a pure monofocal in the distance eye, as I would assume that is the only eye you will use for monofocal astronomy. In theory the average eye has +0.27 um of spherical aberration. There is some controversy on whether or not that should be corrected to zero for the best visual acuity. J&J who make the Tecnis 1 lens put -0.27 um SA into their lens to correct to zero theoretically. Alcon believe the optimum is to have some residual SA and put -0.20 um SA in their lens. B+L believe a residual of +0.0 SA is ideal and make their enVista lens neutral to leave what is in the cornea unchanged. They say it sacrifices some visual acuity but increases the depth of focus and and tolerance for the lens position/eye not being perfect. If you look back at an image I posted about 10 days ago, you can see a graph from B+L that illustrates that point. And if that is not complicated enough, some believe you should measure your own specific cornea to determine what the SA value actually is, and then choose the lens that provides the best SA correction. The often quoted +0.27 for the cornea is only an average. I suspect most surgeons do not do this, and you would have to find one that has the capability and is willing to do it, if you want to go down that road. If you don't, then my thoughts are that the Tecnis 1 or Alcon Clareon are the best choices, depend on who's theory you want to believe, if the objective is ultimate best visual acuity.

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The same logic can be applied to the near eye, but I would argue that ultimate visual acuity is not as necessary in the near eye. In your case you will not be using it for astronomy. There could be an argument for using an EDOF or near EDOF lens like the Eyhance to get a bit extra distance vision. So ophthalmologists that use it call it hybrid monovision. It will work of course, but to get very good close vision you do have to offset the lens. I am convinced with monofocals the optimum offset is -1.5 D. On the Eyhance it may be -1.25 D. And to be realistic one needs to set a target range like -1.25 to -1.50 for a monofocal, and say -1.0 to -1.25 for the Eyhance.

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For sure one can improve vision with monovision by using progressive glasses as well. One reason is that with the fairly course steps available in IOLs there will almost always be some residual sphere and cylinder error that could be corrected. Progressives can do that very well, and also at the same time take out the monovision differential by fully correcting the close eye for distance. I have a pair of glasses that do exactly that, but I seldom wear them. It does bring back the issues of progressive glasses with needing to look up and down to get the right effect. You don't have that with eyeglass free monovision. You have a full field of view.

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There is one issue with using eyeglasses for correction however, and that is when you have an EDOF or near EDOF IOL. These lenses introduce some optical "tricks" to extend the depth of focus, that eyeglasses cannot correct. Eyhance varies the power of the lens from the center to the periphery. The RayOne EMV varies the amount of positive SA from the center to the periphery. And the enVista simply has a larger amount of positive SA residual. None of these optical effects can really be fully corrected with an eyeglass lens. And the other issue is that these lenses do not have as sharp of a peak in visual acuity at their optimum focus point. This makes it harder for the optometrist (really you) to determine "which is better, 1, or 2?" which is the trial and error process used to pick your prescription power. For all of these reasons I think one will get the best eyeglass corrected mini-monovision when pure monofocals are used for IOLs.

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There is the issue of cost, but I did not consider that when making my choices. If I have one regret it is that I should have chosen the minimal power toric instead of the non toric I got for my close eye. This was not a cost decision but was based on some doubt if I would get better vision considering that my astigmatism was irregular. I am now sure in hindsight that the toric would have given me better vision, and it was a mistake not getting it.

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Hope that helps some.

Hi Brad,

My pleasure. Some context. You may or may not have read that my first eye, my left distance (and turns out non-dominant) eye, was done about 4.5 years ago with a Zeiss monofocal. I'm getting 20/15 for distance in that eye all the way in with clear vision to a bit under arms' length... maybe 22 inches although I've never taken a tape measure to it. My "near" eye was done in latter September of this year with the Rayner EMV with an end result - 0.75D from my distance eye. My surgeon told me he typically aims for between - 0.35D to -1.0D offset for mini-monovision with the Rayner lens. When I heard this I was surprised because it meant to me that I'd have very little issue adapting because previously, with my unoperated remaining near eye, I was dealing with a 2 diopter difference between the eyes and I was struggling a bit with that. So anyway, that's the background.

Now given that I have pretty good intermediate (i. e. dashboard, computer) vision with my "distance" eye, that dovetails well with the intermediate range I'm getting from my "near" eye. There's some nice overlap there. All intermediate vision is very comfortable and I can go all day on a computer. My near(right) eye "crisp" range is from about 11 inches to somewhere beyond arms' length. Now, J1 is quite a tiny print size and I'm borderline reading it at arms' length in my near eye alone, but I can read it with both eyes engaged. The difference between a "c" and an "o" or between a "P" and an "F" can be a challenge at arms' length, however. Inside of arms' length to 11 inches I can do it with increasing reliance on my Rayner "near" eye, of course. Inside of 11 inches with my near eye (the Rayner EMV) things become increasingly blurry.

Now, to address my distance vision with my "near" eye. As I previously mentioned I was measured at 20/30 for distance with the Rayner EMV on its own. Nevermind the numbers, but for me just in terms of the experience of it, my "near" eye distance vision is better than I imagined. This was maybe the most pleasant surprise of all. I'm not suggesting it's perfect... It's not as good as my distance eye, but it's not too far off it. I venture to say that if both my eyes were 20/30 I probably wouldn't need glasses most of the time.

I, too, am an amateur astronomer by the way, and it's something I specifically mentioned to my surgeon in the initial consultation 4 1/2 years ago as part of my lifestyle. I think you can achieve an overall 20/20 result (without correction) for distance if you go mini mono-vision. As standard practice, you'd want to get your dominant eye (your telescope focuser eye) set for distance I think (maybe with a monofocal, or an EDOF). If successful, then you're low hanging fruit with an extended depth of focus lens like an Eyhance or a Rayner EMV offset around - 0.75D to -1.0D in the near eye for reading and intermediate (and some distance help too) . It really depends on what you're looking for and what your surgeon says he/she can likely deliver on. It's a conditional probability--If you can get the first eye nailed down nicely for distance, then the rest should fall into place with a very high probability.

After having had cataract affected vision for probably 7 years, I'm stunned I have the vision I have now. When I went into my first consultation over 4 1/2 years ago and my surgeon told me I could be glasses free most of the time I thought it was too good to be true. I've yet to need glasses since my second surgery. The only time I could see needing glasses is perhaps for a marathon session of small print reading at the 11 - 17 inch range. But all I need to do to get my binocular reading vision to kick in is to extend my arms a bit and then my distance eye kicks in. So for all practical purposes I'm glasses-free. I hope this helps.

Regards,

Indy G

Ron,

Thanks for detailed post--I really appreciate the details, even though I do struggle to understand the optics involved. I'm trying my best to learn as much as I can so as to make an informed decision when the time comes to make an IOL choice.

So, if I understand you correctly, using both eyes, you basically can see pretty clearly from about 12" out, correct? Or is that just using only the near eye? The brain, I gather, is able to fuse the images from each eye into what feels like natural accomodated vision (at least with a mini-monovision offset)?

It's interesting to me that your distance eye clarity begins about 20" out, since that eye is -0.25D. I read an ophthalmologist (on either this forum or another) who stated that vision with a monofocal lens set at plano will be blurry at around 10 feet and closer; I didn't think such a lens so close to plano could give good intermediate vision. Perhaps I misunderstood the ophthalmologist?

Your comment about an EDOF or near EDOF lens not being able to be corrected with an eyeglass lens definitely caught my attention. That's something I will certainly have to consider and investigate further. One of the appeals of mini-monovision for me was, should the final refractive result not be as ideal as desired, progressive glasses can be used to compensate. If that's only true for monofocal lenses, that would make me a little reluctant to try a lens like the Eyhance or RayOne EMV.

I also wonder, I am extremely myopic: -8.25 in my left eye, and -9.25 in the right, and wondered if that affects the ability of a cataract surgeon to effectively hit a refractive target. I also think I've read that high levels of pre-existing myopia reduce the benefits of a lens like Eyhance. Any insight on that?

Last question--right now my acuity is not too bad (although the prescription of the progressive glasses I'm currently wearing is not quite right); my main issue is with night glare and haziness from headlights and other light sources. Have you any knowledge about a spectacle lens like the Zeiss Drivesafe, which is designed to minimize night glare? Some of the reviews are quite positive, although I don't know if it would help with cataract-related issues. Although, I wonder, for the middle-age folks who seem to be the target consumer for this lens, isn't night glare usually related to some early changes in the eye's lens, even if there is no obvious cataract?

Thanks again for all your insights,

Brad

Hi Indy,

Thanks for your really detailed reply. It sounds like you've received very satisfying results with your IOLs. That's nice to hear. As I related to Ron on another post in this thread, my own vision is highly myopic, so I don't know how that might affect my own eventual cataract surgery results. Right now I'm trying to do as much research as possible, but I hope I can hold off getting the actual surgeries for another year or two, if not longer.

For all of my life--or at least since I was around 10 or 11, everything from about 4-5 inches out is blurry. So I'm hoping that any change from an IOL will be an improvement! But being able to function glasses-free isn't really an expectation for me, although it would be amazing to be able to go through most of my day being able to see reasonably well.

Right now, the progressive glasses I wear, they, well...sorta suck. Some of this comes from the inherent limitations of progressive lenses, but I think its really compounded by my high prescription and choice of high-index lenses. The intermediate area is very small, so although I wear them through most of the day, I finally did decide to get separate single-vision glasses for extended bouts of both computer work and near/reading work. Also, the ABBE value for these high-index lenses is very low, so that produces some aberrations and loss of clarity. In fact, at my last visit to my optician, she actually said the best thing that could happen for me would be to have cataract surgery!

Regarding your present night vision, using both eyes, the 20/15 left, and the 20/30 right, how clear overall is your naked eye astronomy viewing? Do stars seem pretty sharp and crisp, or would you appreciate maybe some glasses that brought the right eye up closer to the left? How does the moon look, naked eye? Right now, for me, there is a lot of haze around the moon, due to the cloudiness of my natural lens, I guess. It would be nice to see a sharp, crisp moon again. And do you drive without any additional lenses, especially at night?

Sorry to pester you with so many questions, but, well, whatever else can be said about the internet, forums like this really do help connect people with others who have valuable knowledge and insights about specific topics.

Thanks again,

Brad

Brad,

It's my pleasure to answer your questions. Let me first say I think there's considerable hope for you. Do do your research, seek out great surgeons.

As for my naked eye astronomy vision I'd say it's quite good but not perfect. Of course if my near eye's 20/30 distance vision was 20/15 like my other eye things would be better. But I as I wanted unaided reading vision I feel the small compromise was well worth it. I live under fairly dark skies and I can see the Pleiades nicely. The Moon is also quite sharp, mainly due to my 20/15 eye. I can also spot faint satellites. Prior to my surgeries, I could not even see a daytime Moon in the sky. It would just wash out completely. Now I see it without any issue with each eye, independent of the other. I can definitely enjoy watching the stars without feeling I'm missing out on the experience.

In terms of driving, I've not needed correction in daytime or nighttime scenarios. Certainly not in daytime. Could my nighttime driving vision be improved a bit? I expect marginally so, but I've not felt the need to actively seek it out.

Let me know if I can be of further help.

Cheers,

Indy G

Yes, I see very well from about 12" out with both eyes together. Close I am mainly using my left near eye, and at distance the sharpness is coming from my distance eye. They probably contribute equally in the 20" to 60" range. I no longer golf but I expect I would have no excuse missing the ball with a golf swing. For fine work close I do wear some +1.25 D readers.

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To really understand the vision vs distance for the various lenses you need to get your head around the defocus curves. Some examples can be found in this article.

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Review of Ophthalmology PUBLISHED 15 APRIL 2021 IOL Review: 2021 Newcomers

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The curves show visual acuity vs distance. A LogMAR of 0.2 is about 20/30 and considered to be the approximate limit of good vision. The distance is measured in diopters and is more tricky. To convert to distance you divide 1 meter by the diopter value. The more negative the diopter the closer the distance. A -1.0 D distance is 1 meter, -2.0 D is 0.5 meters, and so on. From the curves in this article you can see that a Alcon SN60WF monofocal which is what I have in my distance eye hits the 0.2 LogMAR at about -1.5 D. That is about 2/3 of a meter or 24" or so. I seem to do a bit better than that at 18-20". If you look at the J&J curves they show the range of actual outcomes in a study or a number of people. It is quite wide. From what I have read people that are more myopic and have a smaller pupil size (older people?) have a better near sight outcome. I'm 73 but was not that myopic before surgery (-2 or so). I guess the point here is that vision with a monofocal does not drop off a cliff. It goes down slowly and outcomes vary from individual to individual. So, one has to be careful in using anecdotal results (like mine!). YMMV! The other thing you can see from these defocus curves is that the Alcon SN60WF gets to -1.5 D for near vision, while the Eyhance gets to -1.5 D at LogMAR 0.2. However, this is not an apples to apples comparison as it appears the Alcon curves are with both eyes, while the J&J curves are with only one eye. One has to be careful comparing defocus curves....

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My point on the EDOF type lenses not being as easily correctable with eyeglasses is theoretically valid, but perhaps in real life the differences may be minor. They likely make a bigger difference with the MF lenses like the PanOptix and Synergy. But, it is true that EDOF does introduce optical effects that cannot be corrected by eyeglass lenses. So, if you are looking for ultimate optical quality with eyeglass correction it would be better to stick to a pure monofocal.

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Being highly myopic before cataract surgery is a bit of an issue, but should not be a major concern. It usually means you have a long eye. Some formulas used for IOL power calculation are better suited to long eyes than others. You can find some information on the issue if you google this article.

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Zeiss IOL calculation formulas explained

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I would suggest you want the newer formulas that are more suitable for long eyes used. From what I know about them, the Barrett Universal II, the Hill RBF 3.0 and Kane formulas are good ones. The Hill and Kane ones use artificial intelligence in their derivation. It is a good thing to ask the surgeon what formula will be used and why. Ideally you want to see the predicted recommendation of two or three formulas and discuss which one would be the best. The hope is that the same predicted result is given by all formulas. On the second eye you will know which formula is likely to be best. Here is an article comparing accuracy of the formulas with long eyes.

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Accuracy and Precision of Intraocular Lens Calculations Using the New Hill-RBF Version 2.0 in Eyes With High Axial Myopia

Kelvin H Wan 1, Thomas C H Lam 2, Marco C Y Yu 3, Tommy C Y Chan

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The other issue is that some formulas are more accurate when predicting the outcome when myopia is targeted for mini-monovision. See this article:

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OPTIMIZING OUTCOMES WHEN THE TARGET IS LOW MYOPIA BY ANDREW M.J. TURNBULL, BM, PGDIPCRS, FRCOPHTH; WARREN E. HILL, MD; AND GRAHAM D. BARRETT, MB BCH SAF, FRACO, FRACS

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One thing to keep in mind is that the current version of the Hill RBF is the 3.0 one, and from everything I can see it is improved from the 2.0 and is probably the best all around formula. And if you are really paranoid about this aspect you can ask your surgeon for your eye measurements and use the formulas to do your own calculations. Barrett, Hill 3.0, Kane, and possibly others are on line.

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If you can still see well, I would suggest you try contacts to simulate monovision to see if you like it. Best would be to target plano with your dominant eye and -1.25 to -1.50 with the non dominant.

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I am not sure about the impact of night vision glasses. The Alcon lenses are typically blue light filtering (slightly yellow tinted) to give a young eye colour spectrum outcome. Some believe that improves night vision by filtering out light that may cause flare. Not sure...

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Hope that helps some

Ron,

Thanks again for all the information and expertise. The info regarding the formulas used to calculate IOL powers for high myopia patients is definitely something I will further research and explore, as well as the formulas used to target myopia for mini-monovision.

I plan on giving mini-monovision a try using contact lenses, assuming my vision is still good enough to make that an option. I'm hoping it is, since at present my acuity isn't too terribly bad. But I'll have to see what my optometrist recommends. I did wear contacts for years until dry eyes forced me to give them up. But I may be able to manage wearing them long enough each day to give me some kind of idea of how mini-monovision might work for me. At least I hope so.

Two last questions.

You're a -0.25D in one eye and -1.40D in the other, correct? Are you comfortable driving without any additional lenses, especially at night?

And, second, would you have any suggestions as to how to find a cataract surgeon I trust? Are there any ways you know of to evaluate a surgeon's experience and expertise that can be used to investigate a particular surgeon? I suppose I at least hope to find someone who will sit with me and answer the many questions I have, and it does seem most surgeons--perhaps understandably--don't have an enormous amount of time to spend with each individual patient.

Thanks again for all your help,

Brad

Indy,

It's nice to hear your experience--that mini-monovision has given you such satisfying vision. It must have been really gratifying to receive the much clearer vision provided by an IOL, once your cataracts were removed. How long did you wait to have the second eye done?

As someone who's worn glasses since the age of 8, it's difficult for me to imagine being able to walk around without them. I also watched the video you suggested to another person posting here, the Antonio the Optometrist video showing examples of different levels of myopia. Since my own myopia is so high (-8.25 left eye and -9.25 right eye), everything's a complete blur without some kind of correction. Seeing examples of -1.0, -2.0, and -3.0 diopters is very useful.

If my optometrist thinks it would be helpful for me, I plan on trying contact lenses to at least try to sample mini-monovision. I think my acuity is still good enough to make the attempt practical, but I'm not sure. I'll have to see (pun intended).

Thanks again for all your help and advice,

Brad

Hi Brad,

Whilst I am indeed grateful for my mini-monovision outcome, please know that statistics show a patient satisfaction rate of about 97% with monovision... and it's likely higher with mini-monovision. So my outcome is what should be expected in large part. This is why, in my opinion, it's a very good strategy. It is also the preferred strategy for ophalmologists who get the IOL surgery for themselves from what I have read.

As for trialing monovision or mini-monovision, bear in mind to get a true sense of the experience, you would need to trial it until your brain neuro-adapts, and sometimes that can take weeks or months. Despite that, you can probably get some sense of it with a short trial knowing that things will likely improve even more from that starting point over time.

As for finding a good or great cataract surgeon, there are rankings of eye hospitals online that you can check out. If you happen to live near one of the top ones, you might consider going there.

Lastly, to answer your question, the time between my surgeries was about 4 years. My first eye was set with a monofocal for distance back in 2018. My Rayner EMV in my "near" eye was done this past September. I hope this helps.

Indy G

I tried a lot of different contacts and the one firm conclusion I came to was that the J&J Acuvue Moist were the worst. Extremely hard to handle and despite their name, they seem to dry out during the day. The Acuvue Oasys were much better. But I found the Costco Kirkland Daily to be the best. They are CooperVision MyDay. Next were the Alcon Total1. The newer Alcon Precision1 may be good but I never got a chance to try them. I could go the whole day with the Kirkland lenses. And Costco is good about giving out free samples to try.

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Yes I drive all the time with no prescription glasses, and even at night in the city. Out of the city at night I do try to remember to bring my prescription glasses. We have moose and deer here and being able to see them coming up out of the ditch when you are at highway speed is a good thing.

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Finding a good surgeon is always a challenge. There is the "Newsweek America's Best Eye Doctors 2022" article that you could try to see if there is a high rated ophthalmologist in your area. And there is the RateMD site that can be used to look up individual doctors to see what comments there are. I think the best instrument used to measure eyes is the Zeiss IOLMaster 700, so a further screening tool is asking what they use. Typically this is used with the topography measuring Pentacam. And if you have a particular lens in mind you will want to ask up front which ones they do. It seems they end up in either the J&J camp or the Alcon one, but often do not give you a choice between the two brands.

Here is a real world astronomy example. There is a Mars occultation event tonight where Mars is very bright and will go behind the moon for about an hour where I am. Currently it is about 15 minutes from going behind the moon. I think it is going to look like it is crashing into the moon.

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In any case with no glasses I can just barely see Mars with my distance eye, or with both eyes open. There is no chance of seeing it with my close eye. With glasses I can easily see Mars with either eye, and my close eye which has more astigmatism may even be a touch clearer. With both eyes and glasses it is sharp and easy to see. And of course with my 10 power binoculars and glasses it is really clear and sharp.

I would just add on the screening of the surgeons to be careful with the ones that either want to do both eyes at the same time, or want to do the second eye in a short period of time after the first eye. Surgeons should learn something on your first eye, but to do that your eye has to heal for 6 weeks or more to get an accurate refraction measurement. So, I would look for a surgeon that is willing to review your 6 week outcome before making the final decision on the power selection for the second eye.

Ron,

Thanks for the advice. I definitely would not allow myself to be rushed into having the second eye done before seeing how the first eye heals and recovers. That being said, because I'm severely nearsighted, the unbalance between one eye corrected with an IOL and the still-nearsighted, untreated eye will, I'm guessing, give me problems, although perhaps wearing a contact lens in the untreated eye might help address that.

Yes, using a contact in the non operated eye, is the best solution for the temporary unbalance between the surgeries on each eye.

Indy,

Thanks again for all your helpful insights, they've been extremely useful. I think my next step will be to look into a min-monovision trial with contacts, and I plan on discussing it with my optometrist when I next see her.

I am, of course, also going to keep lurking here on this forum, and will probably from time to time pester knowledgeable and experienced folks like you and Ron for your expertise in the future.

Cheers and happy holidays,

Brad

Doing mini-monovision with contacts before the first surgery is a good idea. I did that. The only caution I would raise is that you likely still have some accommodation and near vision will be slightly better than with the equivalent IOLs. The other thing to be aware of is that contacts worn in the week before eye measurements are taken can interfere with an accurate measurement. Hard contacts are longer, but I suspect you will not be trying them. The upside is that the contacts for your non operated eye can be used to cover the 6 week interval between eyes.