Monovision - First eye for near vision

It is controversial whether one should do distance with the dominant eye, or close with it. Some studies have found crossed monovision works as well or perhaps better than dominant eye distance monovision. I have crossed monovision. But, in this case with monovision being used for 28 years, I would say experience trumps theory, and I would stick with what has worked well for this long length of time. The brain will be used to it.

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It is standard practice to use spherical equivalent which includes astigmatism when setting targets. It would be a mistake to only base it on sphere, and to ignore the astigmatism effect.

It is standard practice to use spherical equivalent which includes astigmatism when setting targets. It would be a mistake to only base it on sphere, and to ignore the astigmatism effect.

For me, the target for astigmatism should be zero, or as close as you can get. If you were to say that you are going to have 0.75 cyl, and did not want to opt for something to correct that, THEN you could use the spherical equiv as a target.

So IMO, the question about cyl for phil09 would point different potential choices if the astigmatism was 0.5D, 2.5 D or 5.0d.

In choosing which lens, the sph number does not usually make much difference in what lens a patient would choose. Most lenses come in a wide range of sph.

My tendency would be to get at least one eye done with RxLAL, but there are things that would prevent that. One would be location. One would be budget. One would be too much astigmatism... In some cases, such as 0.5D cyl and budget considerations combined might make RxLAL less attractive.

I sort of follow your logic, but normally with standard monofocals less than 0.75 D cylinder does not justify a toric, and more to the point, a toric in those lower powers are not available. And when you go into the toric range and spring for the extra cost, you are most likely going to have residual astigmatism anyway. The steps in toric powers are quite large. For that reason one should always consider the combined spherical equivalent including the residual cylinder.

I don't know about a dominant eye. Is dominance meaningful, when the two eyes are largely viewing different distances? I would agree with RonAKA that if my near and distance eyes have worked fine for 28 years, it seems likely they would continue to work well after cataract surgery without switching the eyes for near/distance.

Cylinder was -0.50 at the most recent measurement (for eyeglasses) 11 months ago. I live in a megalopolis, so I figure I am near enough to pretty much everything.

What is your astigmatism (cyl) of your prescription in each eye? I think the max that RxLAL is rated for is 3D. Used to be 2D.

One of the big advantages or RaLAL is that the astigmatism is added after implant, so the axis does not have to be dealt with at the time of implant.

As I said just above, -0.50 D in the cataract eye. -1.25 D in the good eye.

That is unlikely to be too much astigmatism for the LAL. But, you don't really know how much cylinder there is in the cornea until the cornea is measured. The total astigmatism that is corrected by an eyeglass lens is the vector sum of the astigmatism in the lens and the astigmatism in the cornea. They can be additive which means cylinder goes down when the lens is removed in cataract surgery. However if they are offsetting each other, the residual astigmatism can go up after lens removal. You just don't know until the detailed measurements are taken with an IOLMaster and Pentacam.

Those who state a preference usually prefer the far eye to be the dominant eye. Yet research shows that does not make much difference. But if it turns out that your cataract eye is your dominant eye, then almost everybody would be happy to make that for distance. If the cataract eye is your non-dominant eye, do some searching, plus we can provide a link or two. If you do much shooting with iron sights, there could be another thought-- maybe consider making your aim eye to be better focused on the front sight.

Testing which is your dominant eye is easy DIY. With both eyes looking at something maybe two arm lengths away, put your index finger on or just below an object.

Close one eye. If the index finger moved a lot from the target object, you closed your dominant eye.

There are variations.

Expect RxLAL to be about $4500 premium over what Medicare or other insurance pays, which pays for a non-toric regular IOL if your cataract is bad enough. In your searches, you might find more hits on RxSight, which is the company.

Thanks, trilemma. Yes, the LAL is pricey. And with HMO coverage, the entire ~$10,000 cost may be out of pocket. But my eye is very important to me.

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Yes, the LAL is pricey. And with HMO coverage, the entire ~$10,000 cost may be out of pocket.

Maybe switching to a PPO would work better for you. If you are in the US and over 65, open enrollment for 2024 starts soon. Also, only doing one eye now would not be $10000.

Good suggestions, although they don't work for me. My employer is an HMO, and does not offer PPO. And I'm still under 65.

I'm afraid one eye IS $10k, if you want the Light Adjusted Lens - extra cost for the lens, extra cost for the follow-up adjustments. They are VERY pricey!

The part that makes it hard to justify is the LAL does not offer any significant optical benefits compared to a basic monofocal like the B+L enVista IF the targets for the monofocal are carefully selected and hit. The big benefit would be reducing the risk of missing, as well as the ability to make finer adjustments based on your personal preferences. They are able to address smaller amounts of astigmatism, but the benefits of small corrections are also small, so of questionable significance.

Understood, and I agree. But hitting the target (or close) is important to me - if I ended up 0.75 D off from either my near-vision target or my distance-vision target, it would annoy me for the rest of my life. And having had LASIK in the past, I am being told that hitting the target is kind of a crap shoot for me.

Maybe I should consider two different options for monovision:

Option A - RxLAL

Option B - enVista plus LASIK follow-up to correct closer to target.

Option A is tempting - I hear talk of some EDOF, and a handful of very satisfied customers on this forum and around the interwebs raving about great near and distance vision.

Option B is likely less expensive, but to me, outcome is far more important than cost.

Thoughts?

I had thought the follow-up adjustments were part of the package.

Near San Diego by chance? Codet in TJ is about a mile from the US boarder. They have a price list, but it is not clear what that includes.

Last time price for LAL was discussed here it was $5,000 per eye. Maybe I'm remembering wrong, but I thought that was from people who'd had it done.

There are some ways to minimize the risk of missing the target with a standard monofocal. First would be to get two sets of measurements done with the best instruments like the IOLMaster 700 and Pentacam. Then run the measurements through at least 3 different formulas to see how consistent the predicted results are. I would suggest the Hill RBF 3.0, Barrett Universal II, and Kane ones are among the best. You need a surgeon that understands that accuracy is a priority and will work with you in doing the different calculations and then making a decision on the lens power with your involvement. Many surgeons doing standard cataract surgery are used to dealing with elderly people who are just happy to get close enough that glasses can easily correct their vision. They leave it all to the surgeon and don't want to be involved.

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If you are counting on Lasik to fine tune the outcome be aware that it will be better to miss with more myopia rather than less than ideal. Lasik can easily reduce myopia (reducing the steepness of the cornea), but is not reliable in increasing it. Probably best to deal with a cataract surgeon that does both cataract surgery and Lasik, and get their buy in before you start.

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The LAL EDOF is probably being over promoted. I suspect that the enVista has as much or more depth of focus than you are likely to get with the LAL addition of spherical asphericity. To my thinking the big win with LAL is the ability to adjust the power after it is installed, and not the extra depth of focus.

The LAL follow-up adjustments? Yes, the adjustments are typically included in the package price of $10k or so.

You have to be careful - sometimes people quote just the patient's out-of-pocket portion of the total cost, after insurance pays a few thousand.

If you're paying the full cost, figure on about $10k per eye for the RxLAL. Dr. Wong in Austin quotes about that much on his website (Austin Eye), and my surgeon in California charges a little more.

They are able to address smaller amounts of astigmatism, but the benefits of small corrections are also small, so of questionable significance.

I have a set of test lenses. On my RxLAL eye, the -0.25 D cyl lens will make an improvement when viewing my favorite target -- a printed 360 degree protractor with long lines thru the center, and spaced every 10 degrees. I set the target 4.43 meters (14.4 ft) away and slightly elevated.

In fairly dim light, even the -0.125 D cyl lens (labeled -0.12) makes a subtle, but observable, difference, particularly when held at the ideal axis vs 90 degrees to that.

That set even has a plano lens, which loses a tiny bit of sharpness. This is a cheap set (as test lenses go) but expensive compared to an average frivolous toy. I think it has been useful, or at least interesting. Only the biggest sets have the plus and minus 0.125 lenses. My kit goes up to 20D for cyl , which is not at all useful to me. They could have stopped at 6 or 10 IMO. For me, it could have stopped at 2D. The kit has up to 6D cyl both plus and minus. And from 0.25 to 6, step size is 0.25. From 6 to 10D cyl, step size is 0.5. And from 10 to 20, step size is 1 D.

The LAL EDOF is probably being over promoted.

I don't find that.

I have not seen any studies which have shown any documented extension of the depth of focus. Depth of focus has to be extended by a minimum of 0.5 D if it is even to be described as an EDOF lens.

I have not seen any studies which have shown any documented extension of the depth of focus.

I was saying that I have not seen the promotion that you describe.

I was just going by what has been reported here by those who have done the consults for the LAL system.

Many times the price discussed is for people with insurance that provides some of the coverage. So the price stated may be the premium over a basic IOL implanted.

Phil appears to have no relevant medical coverage.