Looking for younger patients IOL monofocal experiences.

Ron,

I think my reply got flagged because i tried including a link to show you the "Terminator Eye" a nickname for Alcon lenses. Google it to see for yourself. It may be your pupils are too small for it to be visible?

I think it is internet myth. I am sure I would have heard of it before if it was a real issue. Seems to me there are a lot more important things to be concerned about when selecting an IOL.

Ron, when you say higher power IOLs, are you referring to people who are very nearsighted or farsighted? I am very myopic and my IOL would likely be in single digits.

I believe it is people who are very far sighted that get into trouble with the Tecnis lens effective diameter reduction. Good question for your cataract surgeon.

Thanks, I will add it to my list.

Do you know anything about Clareon and thier effectve diameter? My power is +30.

I do not know of a reference for the Clareon like the one I provided above for the AcrySof IQ lens. However the main difference between the Clareon and AcrySof lens is the resistance of the new Clareon material to the formation of glistenings, and the edge profile of the Clareon. The Clareon edge is said to be sharper to provide more protection against the formation of PCO. The refractive index is the same for both lenses at 1.55 so the thickness of the lenses should be the same. If you google this information you should find the Clareon document which describes the product.

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Clareon P190018 Physician Labelling

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The specifications on the first page show a power range from +6.0 D to +30.0 D with an optic diameter of 6 mm, so I would expect no reduction in optic area in the higher powers. I did notice in the document that there is a special injector used with a larger diameter nozzle for lens powers over 25.0 D. This would suggest the higher power lenses are larger and would require a slightly larger incision size to accommodate the lens. This again suggests they are maintaining the full optic diameter instead of reducing it to make the higher power lens smaller as is done with the Tecnis 1 lens. The high refractive index of 1.55 is likely what is allowing them to use a full 6 mm optic diameter right up to the 30 D lens power.

I see you are researching Clareon as a potential lens to do an exchange. Here are a couple of articles you may be interested in.

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The open ophthalmology journal Comparison of Visual Outcomes and Patient Satisfaction Following Cataract Surgery with Two Monofocal Intraocular Lenses: Clareon® vs AcrySof® IQ Monofocal Smita Agarwal1, Erin Thornell2

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The ophthalmologist Clareon® IOL: A New Monofocal Platform

Highlights from Alcon’s Satellite Symposium,

held on October 9, 2017, at the XXXV

Congress of the ESCRS, Lisbon, Portugal

Thank you so much for your reply and considerations!

Yes, that indicates that Alcon Clareon are maintaining the full optic diameter for high power lenses. Fingers crossed.

Do you have a lot of side effects or blurry peripheral vision?

at night in the dark the whole iol lights up.

Hi Soks,

Can you explain what you mean when you say the whole IOL lights up at night? What do you see at night?

light flare starts at the centre and flows towards the edge of the iol. lighting up the edge as a circle of light and light spokes going go the edge.

look at the logo of american academy of opthalmology.

do you see this when looking at outdoor lights? car headlights, streetlamps etc?

any light but mostly street lights when there is no light source on my eye. for example if i am indoors with light on the pupil will contract and the street lights outside will be fine. but if i am in the car with no light source on me then things will try to flare.

in movie theatre the light from the movie screen will help contract the pupil. i can take lumify or alphagan and contract the pupil but that makes night time darker.

i have the same issue at night if the light strikes the edge, it lights up the whole IOL on top of my vision. i have multifocal from 2007 and im 31

Thanks for replying. Any other vision issues? Are you happy with the multifocal? Which brand IOL did you use? Just the one eye? Do you get the cat eye reflection? Are you satisfied overall with your vision in that eye? 20 questions, sorry!

looking back I think I would've been happier with a monofocal. Keep in mind though my multifocal IOL is from 2007, so the technology might be a little better now (however there are still some fundamental design aspects of multifocals that remain the same today, like the splitting of incoming light) . Because multifocals split light into multiple focus points, you lose contrast in the images that you see (which can be extremely noticeable in low light situations). My other eye doesnt have an IOL, so I can easily make the comparison between eyes. The multifocal eye makes everything seem darker than my natural eye which is a huge downside of the technology. Because the multifocal splits light, your brain is only using a portion of the light to generate an in-focus image (and consequently everything looks a bit darker and less contrasty than a normal 100% light-using eye). Another issue i have with the multifocal is ghosting. Because near & far vision are simultaneously in focus, whenever i look at an object far away, my brain also displays a ghost image of the same object using my near focus point, but my brain knows to try & filter out (or ignore) the near focus point image since the object is far away and only the distance point on my IOL is providing a clear/usable image. However the brain is not perfect at filtering out these images so at times you see a duplicate ghost image superimposed over the clear (in focus) image. This becomes even more noticeable at night. My brand is called ReZoom but its no longer available on the market. Even with all the negatives I just listed, I can't deny its very nice to have a second focus-point for viewing near objects without needing an extra pair of glasses (i wear regular single vision glasses during the day to correct my distance vision). I ended up very myopic after my IOL settled in but it actually works ok because my other natural eye also needs glasses. For reference, im only 31 years old

interesting. Is it weird to have near and far simultaneously in focus? How myopic are you? When you wear distance glasses, does it take away your near vision?

its not as weird as it sounds actually. Your brain selects the appropriate image to use (i.e. either near or far) and ignores the other one. As time goes on your brain gets better at filtering out any optical disturbances (like ghosting), and this process is called neuroadaptation. My multifocal eye has two clear focus points without glasses, one is at 8 inches and the other is at 19 inches. So basically without glasses, I can see my phone clearly at a very close distance and a computer monitor at semi-intermediate distance (19 inch is sort of between near & int). The prescription i wear on this eye is -2.0 SPH with +0.5 CYL, which basically shifts my 19" focus point to distance, and the 8" focus point to around 11-12 inches. So i don't lose the near vision when i wear glasses for distance, the glasses just shift both my focus points further out.

The multifocal undeniably gives you more focus range compared to a monofocal (however im not convinced that the drop in image quality and optical disturbances are worth it). You can still see near/int/distance with a monofocal, you just have to wear multiple glasses to achieve all of those. My next eye will 100% be a monofocal lens because I need to be able to drive at night for my job. If you care about night driving at all, my strong recommendation is to consider the monofocal

I don't drive. I am a high myope and i see starbursts around lights at night as part of my normal vision. But i am easily anxious and a perfectionist. I am -10.5 in contacts with about a 1.5 add for reading. I could sacrifice some distance if i could keep my near vision close to what it is now - fuzzy down to about 18 ish inches then clear. If i had to wear readers for 18ish inches or closer i could deal. What scares me is waking up and being totally blind (like what i am without contacts in) for the things i do everyday like cooking, using iphone etc. Kinda wondering if i can use my high myopia to my advantage with a monofocal.

That still sounds crazy to my brain but i guess it would be similar to wearing contacts. The more you correct for distance the less you get for near. At my age anyway (45.) You are not very myopic at -2 so I can see how balancing might not be an issue for you between the eyes. Are you -2 in the other eye?

Yes my natural eye is -2.0. Without glasses my vision is great up close but i need regular single vision glasses for walking around & driving. But for computer & phone i dont wear glasses (which is good for me because i work at a computer all day)

just remember after cataract surgery your eyes are going to focus fundamentally different then the way they do now. If you're near or farsighted before the surgery, i dont believe it has any affect to the way your vision will behave after surgery. The most important thing is undestanding what refractive target you want to aim for (for ex, clear focus at 19 inches away corresponds to a target of -2). You an actually calculate the distance for each diopter value using a formula online. If i was targetting to have -2.0 after surgery (which corresponds to 19") i would expect to only have objects clearly in focus in the range of maybe 18-20 inches (with 19" being the absolute clearest point). As you go closer/further from the sweet spot point, focus is gradually lost without the help of glasses

Might be a dumb question but how could i keep my similar vision now? essentially plano at distance ( wearing contacts) with a near focal point of 18 ish inches before putting on reading glasses at +1.5?

If you went with a monofocal set for -2.25, the sweet spot for clear vision without glasses/contacts would be 17.5 inches (which is pretty close to 18 inches). If you wore a contact to correct for distance, your near vision would be extremely blurry without readers or taking the contact off. You would basically need to wear readers with +2.25 to see clearly at 18 inches while wearing a -2.25 contact. If you used a +1.5 reader I don't think it would be strong enough to counteract the -2.25 on your contact. I would confirm all of this with your doctor but this is how i believe it would work. Another thing to consider is that setting the IOL for, say, -2.25, is not a guaranteed outcome. Usually they can get pretty close to the target (i think 90% of surgeries are within +- 0.5D of the target). So if you asked for -2.25, you should be also be okay with a possible outcome of -2.75 (14 inch) to -1.75 (23 inch). 90% of the time you would end up somewhere in this range (hopefully right at 18 inch)

I appreciate you taking the time to explain this to me. What I think I meant was, is there a way to get close to plano with an iOL for distance that also lets me read at about 18ish inches? For example, could i get Eyhance and offset it about 1D? Trying to avoid a contact lens if i can.

No prob! My understanding is that each premium IOL (whether multifocal, EDOF, or another) varies in its abilities to provide near vision. I've heard the Eyhance is designed for distance, but allows for a little more intermediate compared to a standard monofocal. i wouldn't count on 20/20 vision at 18" with a lens like this. Imagine with a standard monofocal set for distance, the intermediate vision is probably poor around 20/60 or worse, but with an EDOF like eyhance, maybe you could improve that intermediate vision to 20/40 or so. You still might want to wear glasses to be comfortable reading for long periods, but it would be better than a monofocal. With eyhance you dont actually have a second focus point (like you do with a multifocal). As a result i believe the optical disturbances are less but the vision you get at the intermediate range is also not quite as good. Even with a multifocal though, you dont get to specify a target for both focus points (its only for the distance point). The other points actual focus point would depend on the manufacturer (sometimes they say the near point has a 2.5 diopter add, so you could do the math to figure out where the near point would actually end up)

If you are asking about how to get it with an IOL and no contacts, then that is pretty close to what a basic aspheric monofocal gives you. My eyeglass prescription with a AcrySof IQ monofocal is 0.0 Spherical, and -0.75 Cylinder. I have 20/20 for distance. I see down to about 18" in bright light or black text on a white background on a computer screen with the IOL eye only. An Eyhance and Vivity would give you some margin for error and let you see a little closer. My 18" seems to be a little closer than most get, and I attribute it to the residual astigmatism. There seems to be some variation from person to person, and some report close vision starts to jam out at 24". With my vision I use some +1.25 readers when I need to see really clearly.

And to be clear I don't think if I had a monofocal IOL in both eyes with distance correction, I would not be comfortable using a computer with no glasses. 18" is too far from the screen. It might work if it was a much larger screen than the 24" one I am using. I currently get my computer vision from the other eye which is corrected to -1.25 D with a contact. That lets me be comfortable at 12" or so.

This is so helpful, thank you. You mentioned a website that could help do the math for diopter/distance?

If you take 1/diopter it gives you the distance away in meters. For example, if you assume 2.0 diopter target, you do 1/2 which is 0.5 meters. 0.5 meters is the same as 50 cm. If you remember 2.54 cm equals one inch, you can take 50/2.54 and you'll get 19.68 inches (which is the theoretical focal length for that power)

What I will add is that you should look at the defocus curve for the lens you are considering. Then you will know at what distance you are likely to have good vision. You have to keep in mind that these defocus curves have an error bar associated with them. So there is always a +/- band where you could end up as an individual, compared to the average.

by the way im not a doctor or anything, so always confirm with your med professional anything you do or assume about your eye. I'm just sharing what ive learned over the years of researching about eye problems

okay so if i offset for -1D with a typical monofocal, my focal point is about 3 feet? But if i keep it to plano my focal point is infinity?

Do you happen to know how blurry things get when you are outside of your focal point? I'm super blind with no contacts - after 3 inches from my face its a total blur. i can only see shapes and colors. Do monofocals behave the same way?

Understood you are not a doctor, thanks!

Hi Ron,

I don't quite get the defocus curves yet. For example, if a lens peters out at -1.5D, at what distance is that, and how blurry is the vision from that point inward? i am blind as a bat from 3 inches out with no contacts, is the blur similar? I wish there was a photo or video that showed what it would be like. Thanks.

One last crazy question - what would happen if i got an IOL to match my regular eye at -10.50? Would I see as I do now with contacts?

the range of focus varies depending on your pupil size and whether your lens is set for near, int, or distance. In general, the further distance your lens is set for, the more range around the focus point you'll get in terms of clarity. for example, if your lens is set for super near at 8 inches, you might only have acceptably clear vision without glasses from 7.5-8.5 inches. However if your lens was set for 36 inches, you might have acceptably clear vision without glasses from 34-38 inches. The further out, the more the range you get around the sweet spot point. To be safe i wouldnt assume too much of a range if youre planning a near target

On a defocus curve you divide 1 meter by the defocus D value. A defocus of 2 D is 1/2 = 0.5 meter. A defocus of 2.5 is 1/2.5 or 0.4 meters, and so on. Keep in mind there is no abrupt drop off. It is a smooth curve and vision just decreases with the curve. A value of 0.2 on the vertical axis is considered to be the limit of good vision. If you google your preferred lens and defocus curve and select images you should find some examples.

"One last crazy question - what would happen if i got an IOL to match my regular eye at -10.50? Would I see as I do now with contacts?"

Yes. But of course you would never ever want to do that. The default choice in selecting a lens is to see plano at distance. Then your default condition is just like pretty much anyone that is older and has lost their ability to focus close. You will start to lose sharp vision at about arms length.

I currently wear a -9 in one eye to emphasize near vision, the focal range to read this on my iphone for the -9 eye is about 14 inches to 21 inches. My other eye set for plano at -10.5 has a near focal point of 22 inches to 36 inches. So, it seems the plano has twice the range but starting further away. You are very smart!

Does this mean i could reasonably replicate my -10.5 focal range with plano? I wonder if Eyhance would give me even more near if i sacrificed -0.5D. I have large pupils, not sure if that gives me more range of focus.

You have been so generous with your time. I will ask the rest of my questions to a surgeon. Thank you!

I only need one eye replaced. I am a high myope. I am concerned I will have anieskonia after having one eye set to plano because of my high Rx. So i actually have considered setting the lens to match my blind eye if it meant leaving the other eye alone. If my near vision stayed the same as my -10.5 vision - a focal near point about 22-36 inches, it is something i do sometimes think about.

Thanks Ron, i will seek that out. It's reassuring to hear it is a smooth curve - there have been some posters on here who emphasize how "blind" they are up close. What is the definition of the limit of good vision? 20/30?

Okay! I just did some quick math. If i get the Eyhance and off set it by -.5 I should have a near focal range of 18ish inches. This would nicely balance with my regular eye which is plano and a focal range at about 22 inches. if my calculations are correct, that's not bad.

Sorry for being confused - but how is it possible to wear a -10.5 contact to correct for good distance vision but at the same time provide good near vision from 22 to 36 inches? Maybe I'm missing something. Maybe your -10.5 correction isn't meant for giving you good distance vision, it's for giving you the int/near vision only? I'm also a little confused by your use of the word plano. To me this means your vision doesn't need any correction to see far away. As an example, if my surgeon targets plano for my cataract surgery, it means the lens is set so that i can see perfectly in the distance with no need for glasses or contacts. I would still need reading glasses though to see up close

Another thing to consider with focal range is the fact you don't have an IOL implanted yet and your current vision range likely won't equate to that of the IOL vision range (since your natural lens still has some ability to accommodate & help adjust the focus over a bigger range).

My understanding, which may not be correct, is that the issue with having one eye corrected with an eyeglass lens and the other with an IOL is that it gives your brain two different image sizes (anieskonia as you say). And the reason I believe is where the lens is located. The eyeglass lens is a long way from your eye and lens in the eye. However, a contact lens is much closer and not that far away from your eye lens, and right on top of the cornea. My thought is that a contact lens in the non IOL eye would not cause any significant issues of anieskonia.

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I am also thinking that the main issue is the lens location, and not so much the anisometropia. But this would something to question the surgeon and optometrist on.

I believe 20/40 is considered acceptable for driving in our province.

I'm not sure haha. My Rx is -10.5 to give me 20/20 (i used plano to define 20/20) at distance. Things are fuzzy for near vision until i hit about 22 inches. Then after about 36 inches the font is too small to read any longer.

You make a good point about IOL vs normal focal ranges. But if i can still get the IOL to near focus at 18 inches thats a pretty good balance, right?

There was a fellow here who posted and he had image size differences doing one monofocal at -15 and -13.5 in his regular eye. Contact lens did not help. So i am a bit worried. He disappeared from the forum however so i dont know what became of him. I will ask the surgeon though, thanks.

you must still have a lot of accommodative power in that eye if you can see 20/20 at distance with the contact on, and, at the same time, read things clearly from 22-36 inches. If you had a distance IOL implanted you wouldnt be able to see from 22-36 inches without the help of glasses (due to zero accommodation). Another thing to consider is that as you get older, your ability to see that 22-36 inch range while wearing the contact for distance could become more difficult since you lose that natural accommodation. I agree you want both eyes to have a similar focus distance or else your brain might produce double images. Ive heard, as a rule of thumb, you dont want more than 1D difference between the eyes, or else you could run into issues

"There was a fellow here who posted and he had image size differences doing one monofocal at -15 and -13.5 in his regular eye. Contact lens did not help."

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I am not sure what you are talking about when you mention these powers? Are these IOL powers, or eyeglass or contact powers. They seem extremely high if they are eyeglass or contact powers. The difference is not that high though.

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My anisometropia with no glasse, one IOL eye, and one natural eye is about 2.0 D. My natural eye is about -2.0 D and the IOL eye 0.0 D. I don't really like it that much for vision, because it leaks a bit of a hole in the depth of focus that I need for the computer. If I correct my non IOL eye with eyeglasses (correction in that eye only) I do feel a bit dizzy when I put the glasses on for the first few minutes, but it goes away. With glasses I have the very best vision, but I prefer the contact lens correction which leaves me at -1.25 D in the non IOL eye. It seems more natural but my vision suffers slightly.

"I only need one eye replaced. I am a high myope. I am concerned I will have anieskonia after having one eye set to plano because of my high Rx."

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One other option to consider is putting an IOL in the other eye, even though it sounds like you do not have a cataract in it. I believe some insurance companies and healthcare systems are sympathetic to someone who has to have one eye done, and is left very unbalanced due to the other eye. The other consideration is that if you got a cataract in one eye, it seems inevitable that you will get it in the other eye too.

He was extremely nearsighted - those numbers are his contant lens Rx.