Seek opinion/views/suggestions for Cataract IOL
Posted , 4 users are following.
Hi I am a 55 years old male having cataract in both eyes. I believe am not getting the best advice from the eye specialist and chair time. I am ignorant about the IOL and other terminologies , so please excuse my ignorance. I have been categorized as having driving blindness until i get my cataract surgery done. My overall vison both day and night are very blur with prescription specs.
My current specs are progressive lens with the following prescription
RIGHT - SPH (-4.50) -CYL(-0.75)-AXIS 120
LEFT - SPH(-6.50) -CYL (-1.50)-AXIS 55
NV-ADD is +1.75
Visual acuity is 6/7.5 in both eyes with glasses.
I have been to the optometrist thrice in the last 18 months to keep increasing the specs power and cannot any further improve my vision by correcting lens power.
The ophthalmologist has checked has stated current vision is
6/12+2 in the right eye and 6/12-2 in the left eye with glasses.
He has suggested cataract surgery with a myopic target and target is intermediate vision, point of focusing being approximately 60 cm.
I wish to / want to have my say. I am okay wearing specs after surgery.
From my weak understanding of reading this community forums discussions
I would like my LE(non dominant I think) to use an IOL for seeing close to intermediate , reading/viewing computer screen. I would like my RE ( dominant ) to use an IOL for far/farthest distance like driving , hiking viewing.
I see discussions of mini monovision which appeals to me . Like for LE use Alcon Vivity for reading up-close/to intermediate, and the RE with AcrySof IQ monofocal distance for seeing things farther away clearly. I do not what D stands for nor what to choose with the above lenses. I came up with this above sef suggestion piecing together without understanding correctly so i could be completely wrong too,
So please can i have some suggestions and guidance. I am completely new and green to this .
Thank you all in advance.
0 likes, 12 replies
Myope_PSC hifly75872
Edited
D stands for diopter (dioptre). It basically means Lens Power.
Here's where the D goes in your prescription:
RIGHT - SPH (-4.50D) -CYL(-0.75D)-AXIS 120
LEFT - SPH(-6.50D) -CYL (-1.50D)-AXIS 55
NV-ADD is +1.75D
It seems to me that a 60cm (24") focal point is close to what you currently see through your near vision add (NV-ADD) portion of your glasses. That's the lower section of your glasses. Someone please correct me if that's not correct.
1 meter / 1.75D = 57cm focal point
You'd need progressive lenses to give you a full range of vision again if you choose to go with the 60cm focal point.
You have to decide what vision you'd like to end up with and how much change you can accept. I've just gone from being myopic (nearsighted) to having good distance vision and losing that near vision. Indoors, I now need reading glasses for near vision. I could also get progressive glasses instead of the readers. I'm happy with that decision. Others are very happy remaining nearsighted and using progressive glasses.
Then you have to communicate what you want to your ophthalmologist. You shouldn't have to explain it diopters. If you explain it as distances then the ophthalmologist figures out the rest.
If you decide that you want the mini monovision you described then the ophthalmologist needs to know that you want good distance vision in your dominant eye and intermediate all the way to reading distance vision in the eye with a Vivity lens.
If you search google for "J&J Eyhance versus Alcon Vivity" you'll find a post. He explains that a Vivity lens set to a target refraction of -0.5D should result in "reading range of 40 to 50 cm (16 to 20 inches)".
Here's a post from Mike who chose to keep his near vision: https://patient.info/forums/discuss/surgery-next-week-near-monofocal-both-eyes-2-5-783398?page=1#3853719
Here's a post about my recent distance vision + intermediate choice:
https://patient.info/forums/discuss/vivity-or-eyhance-which-to-choose-782792?page=2#3854011
Ron has researched mono vision and mini monovision and understands it well so hopefully he'll see this topic and share his thoughts.
hifly75872 Myope_PSC
Posted
Thank you Myope. I will read to the shared links to gain new understanding.
RonAKA hifly75872
Edited
As @Myope_PSC has explained the "D" stands for diopters, then same units used in your eyeglass prescription. For example your right eye is -4.5 D, which is moderately myopic. Your eye's optimum focal point can be determined by dividing 1 meter by the diopter number, or in your case 1/4.5= .22 meters or about 8.5". That is why myopia people can see so well close up.
I would say it is most common to set the target for a lens in diopters. That is what the cataract surgeon sees when they enter all your eye measurements into the computer program. It will display what your outcome diopter is predicted to be with each IOL lens power available. When you want distance vision the ultimate target is 0.0 D. However it is common practice to target a slightly myopic number of about -0.25 D. The reason is that if you go into the far sighted + territory your closer vision will be negatively impacted.
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I have mini-monovision with monofocal lenses. My right eye was targeted for -0.38 D and ended up at 0.0 D. I see a bit better than 20/20. My left eye was more complicated due to astigmatism, and if I had it to do over again I would have done it a bit differently. When astigmatism is not a complicating factor I would suggest a target in the near eye of -1.5 D, and if you can actually land in the zone of -1.25 to -1.50 you should be good. My eyes have been tested twice since surgery and one said I was at -1.0 D and the other -1.25 D. I could use a bit more myopia, but these things are not exact.
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The simplest and least expensive way to do mini-monovision is with monofocal lenses. There is no extra cost and the potential optical effects of EDOF lenses are avoided. I would do the dominant eye first for distance (target -0.25 D) and a Alcon AcrySof IQ Aspheric lens would be fine, or the latest version called Clareon if available where you are is a bit better. The second eye would use the same lens but with a target of -1.5 D. I would wait 6 weeks before doing the second eye so that it fully heals and you (and your surgeon) know what the outcome was. That can help with accuracy on the power needed for the second eye.
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The other option is to use an Eyhance or Vivity in the non dominant eye. However to give as good close vision as the -1.5 D monofocal, they should be targeted to be myopic as well. The Vivity in my view needs to be targeted to -1.0 D, and the Eyhance to 1.25 D. I talked to my doctor about the Vivity option and he talked me into staying with a monofocal.
john20510 RonAKA
Posted
why did your doctor talk you out of vivty did he say why he was against it
RonAKA john20510
Posted
It was a number of factors. I have irregular astigmatism in the eye that was considered for it. The Vivity does come in a toric, but the surgeon kept flip flopping on whether or not I was suitable for a toric. I asked him what his success was with the Vivity, and he told me that he had put it in someone that was very particular and was not satisfied with it. I think he classified me as a similar candidate and was thinking I would be another unhappy patient with a Vivity. I guess if I was insistent on it, he would have done it. However, I decided some time ago that my preferred route to go was with two monofocals and the close eye targeted to -1.5 D, and that I would not go with the Vivity unless the surgeon was really certain that it would be good. He was not, so I went with two monofocal lens. The first was the AcrySof IQ and the second was the Clareon which was not available when my first eye was done. Both are aspheric.
hifly75872 RonAKA
Posted
Thank you Ron.. I am yet to fully grasp the proper understanding of your valuable suggestions.
My right eye the dominant eye which i choose to support long distance farthest driving, walking etc,,driving day and night.
is to use Alcon AcrySof IQ Aspheric lens set at ( target -0.25D).
Here the target -0.25D why is this chosen what is the reason? Thanks.
My left eye the non dominant eye which is to support reading , computer viewing , cooking etc.. i support myself from working from home using the computer i spend 8 hours a day average,for this
is to use Alcon AcrySof IQ Aspheric lens set at ( target -1.5D).
Here the target -1.5D why is this chosen what is the reason? Thanks.
The above two combination will it come close relieving me of not having to use prescription glasses and also help cover intermediate distance. I could really do away with glasses.
I am open to all suggestions.
Thank you
RonAKA hifly75872
Edited
IOL powers come in steps of 0.5 D, compared to eyeglasses which are in steps of 0.25 D. When you are targeting best distance vision you ideally want to be left at 0.00. However it is unlikely with the course steps that IOL's are available in, that you can achieve exactly 0.00 D. The surgeon (and you if you want to be involved) will in almost all cases be faced with a decision between powers which will leave you slightly under or slight over or positive. You do not want to be positive (far sighted) as that will reduce your near vision. Surgeons will be very familiar with this and will choose a power to ideally get you slightly under or negative. The other issue is it is not possible to exactly predict what power you need, and there will be some error. That is another reason they target to be under corrected.
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The target of -1.5 D is chosen for the near eye as it is enough to let you read at about 12" or so, but does not impact the intermediate vision, and combined with being distance corrected in the other eye does not impact total distance vision.
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I would choose the Clareon version of the lens over the AcrySof IQ if it is available. Where I am, it is a $300 per lens extra cost. But, if not available it is not a big deal. I have one of each. Long term vision MAY be better with the Clareon.
RonAKA hifly75872
Edited
Since your eyeglass prescription indicates some astigmatism (cylinder) you should have a discussion about whether or not a toric lens to correct astigmatism is warranted. With basic public heath care funded cataract surgery this issue is ignored as it is expected any residual astigmatism will be corrected with progressive eyeglasses after surgery. However, if you objective is good vision without eyeglasses it is best to correct astigmatism with a toric IOL if one is warranted.
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Astigmatism with an eyeglass prescription is not an accurate indicator of whether or not you will benefit from a toric lens. That is because the total astigmatism is a sum of what is in the cornea, which will stay after surgery, and that in the natural lens which will be removed. The only way of determining how much astigmatism will remain after surgery is by having a topographical measurement made of the cornea. From that they can predict residual astigmatism. In my case the eye that had the worst astigmatism ended up with the least amount after surgery without a toric. The one that started the best ended up not as good. Depending on the system you are in you may have to pay extra for that exam and measurement. It is worth having the measurement done if you plan on going eyeglasses free. Normally more than 0.75 D cylinder can be corrected with a toric, while less than 0.75 D is not worth it. The minimum power toric can make it worse.
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Something to discuss with the surgeon at your first consult.
hifly75872 RonAKA
Posted
Hi Ron,
So with i can use the first message reply lens suggestion except that i need them to be toric to help correct / support the astigmatism. Prior to any procedure is to have a n topographical measurement made of the cornea to understand the astigmatism as best as possible before hand.
Thank you
RonAKA hifly75872
Edited
At your first appointment with the surgeon you should ask to be measured to see what your astigmatism after surgery is predicted to be. If it is over 0.75 D and you want the best vision without glasses then it is best to get a toric for the eye(s) that are over 0.75 D. You may need a toric in one eye, both, or in neither.
Myope_PSC hifly75872
Edited
You might find this interesting Ron. I learned recently that there is both anterior and posterior corneal astigmatism. Anterior astigmatism is probably what gets measured most often.
I went to two opthalmolgists offices. Both used an IOLMaster 700. One used Barrett Universal II and the other used Barrett TK Toric. The office using Barrett TK Toric found 40% more astigmatism in one eye and 60% more in the other.
RonAKA Myope_PSC
Edited
That is interesting. My surgeon is not all that forthcoming on his methods. I believe my eyes were first measured with a IOLMaster 700, and over a year later my second eye was measured again with an IOLMaster 500. I believe the 700 can measure the thickness of the cornea and possibly both types of astigmatism. Not sure what readings he used on the second eye. About all the detail he gave me was that he estimates astigmatism with two methods and most times it turned out to be between the two measurements. He said the same when my wife's eyes were done. As for formulas he said he used the Hill RBF V2.0. I see that Dr. Hill has now come out with a V3.0 of the formula. It is good that methods are continually improving. Sometimes I wonder if doctors keep up with it all. The surgeon I went to is a professor at our provincial university so I hope he does...