Need help with IOL selection
Posted , 9 users are following.
I'm 65, have cataracts in both eyes. Worn eyeglasses since I was 16 for being nearsighted. I was told I have 2 diopeters of astigmatism and that a toric IOL could correct that, but I am on a fixed income and can't afford that. So I was told I could have a monofocal lens implanted. My cataract surgeon said since I have been myopic most of my life, and I spend a lot ot time on my computer, I should go for near/intermediate vision, rather than distant. He said new eyeglasses would correct whatever the IOL doesn't correct. I think intermedate vision would be better for me. From my eyes to my computer is about 24-26 inches. When I see the surgery scheduler/technician later on, do I tell her I want my IOL set for 24-26 inches or do I just say intermediate vision? From discussions I have read on this forum, it seems to be just a personal choice about how to set the IOL. Is that right? I appreciate your help.
0 likes, 15 replies
RonAKA zerlinagirl
Posted
The basic problem that you have is the 2D of astigmatism. If you don't get toric lenses it will be there anytime you do not have glasses on. So you could get your eyes set to 12-15" for reading, or set to 24" for computer work, or set for distance, but all of these options will still be compromised by the astigmatism when your glasses are off. All you are choosing is the distance where you will have some vision without glasses but compromised by astigmatism. With progressive glasses you should see well at all distances like you probably did before cataracts.
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If you want to see best without glasses at 25" then you will want to be left at about -1.6 D without considering astigmatism. However about 50% of your astigmatism will impact your vision without eyeglasses so you may want to target about -0.50 to -0.75 D with the IOL. The 2D of astigmatism will add about another -1.0 D to that.
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But, all considered I would just tell the surgeon what distance you want to see best without eyeglasses. They can compensate for the residual uncorrected astigmatism.
zerlinagirl RonAKA
Posted
Thanks, Ron. Also, I was talking to a friend in another state who recently had cataract surgery with a regular monofocal lens and she told me that although she sees better now, she seldom drives at night any more because the oncoming headlights bother her, She said she didn't have the problem until after the surgery. I also read somewhere that after cataract surgery some people become sensitive to light, or need more light, Some have to wear sunglasses indoors or some need extra bright light to read. I am going to assume that only rarely happens. Or have you come across those complaints in your time on this forum?
RonAKA zerlinagirl
Posted
By and large I see few complaints with monofocals other than they do not give you the full range of vision from near to far. Most of the complaints are with the "premium" lenses such as PanOptix, Synergy, Symfony, and sometimes even with Vivity, and Eyhance.
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This said, best vision at night can always be obtained with eyeglasses even with monofocals set for distance. IOLs are not as precise a correction as eyeglasses and eyeglasses will correct any residual sphere and cylinder left by the IOL.
vasily48550 zerlinagirl
Posted
I told my surgeon I want my IOL set for intermediate vision, distances 60 cm to 1 m, probably target -1.25D. What I've got is the best focus around 40cm to 50cm, and I need glasses -1.5D to get the best vision for distance. Given that this is glasses, perhaps the IOL is indeed set for -1.25D. So, I don't know if I've got what I asked or not. Perhaps you should have a more detailed discussion with your surgeon to make sure you understand each other very well.
RonAKA vasily48550
Posted
My experience is that the surgeon targets IOL correction based on eyeglass prescription. A 0.5 D step in IOL power is about equal to 0.35 D at the eyeglass plane. If you need -1.5 D for best distance vision then that is what you got. That is a good amount to have in the near eye of a mini-monovision configuration. Best vision will be at 1 meter divided by 1.5 D or 67 cm. This is approximately what I have and I can see fairly well down to about 33 cm.
zerlinagirl
Posted
Thanks, Vasily. I hope you are pleased with your intermediate vision. Do you have astigmatism like I do? How well can you see without glasses? I don't really understand what -1.5D or -1.25D means, although I've seen numbers like that a lot on this forum. RonAKA said I should just tell my surgeon I want intermediate vision without glasses and he can work the rest out
You said you don't know if you got what you asked for. I have heard it said here that surgeons don't always hit their refractive target, and probably their technicians don't always get their measurements exactly right. And then, of course, results will vary from patient to patient.
vasily48550 zerlinagirl
Posted
According to the records, my implant is "Lens Tecnis Eyehance Toric Ii 1‐Pc 13.5d Cyl1.50". I understand this means 1.5 diopters of astigmatism. For the other eye I wear contacts with CYL -0.75D, which means -0.75 diopters of astigmatism. Before cataract, both eyes were CYL -0.75.
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You might be right. I asked surgeon's assistant if they use ORA, and I was told they don't. I hear ORA is recommended for the best visual outcome. I understand this is a technology that allows measuring the optical power of your eye during the surgery and thus hitting the target more precisely. I did my surgery in Kaiser Santa Clara.
RonAKA vasily48550
Posted
Keep in mind that an IOL diopter results in about 75% of that power at the eyeglass plane. So a 1.5 Cylinder gives about a 1.1 D effect. You might be slightly over corrected with the 1.5 D Tecnis lens. Alcon makes a 1.0 D cylinder toric which would give about 0.75 D of cylinder. It may have been more suitable. I believe 1.5 D is the minimum toric power that J&J make.
Myope_PSC RonAKA
Posted
J&J Tecnis also makes a 1D cylinder power toric at the IOL plane. It is 0.69D at the corneal plane. In Canada, Eyhance torics cover 1D to 8D. (1.00D 1.50D 2.25D 3.00D 3.75D 4.50D 5.25D 6.00D 7.00D 8.00D)
Myope_PSC
Edited
J&J Tecnis Eyhance Toric brochure image attached:
RonAKA Myope_PSC
Posted
Interesting. It would seem the surgeon was expecting astigmatism to increase with the surgery if you were at -0.75 before. Have you had the eye checked to see where you ended up after the toric implant?
Myope_PSC RonAKA
Posted
My post was just info about J&J's Eyhance toric lens properties:
Model / Lens Plane / Corneal Plane
DIU100 / 1.00 D / 0.69 D
DIU150 / 1.50 D / 1.03 D
DIU225 / 2.25 D / 1.54 D
DIU300 / 3.00 D / 2.06 D
DIU375 / 3.75 D / 2.57 D
DIU450 / 4.50 D / 3.08 D
DIU525 / 5.25 D / 3.60 D
DIU600 / 6.00 D / 4.11 D
DIU700 / 7.00 D / 4.80 D
DIU800 / 8.00 D / 5.48 D
vasily48550 RonAKA
Posted
The optometrist I've seen 4 weeks after the surgery gave me the following prescription for glasses for the operated eye: SPH ‐1.50 CYL ‐0.25 AXIS 114. It looks like the IOL slightly overcorrects. I double checked my older prescriptions. Indeed, I was prescribed contact lens CYL -0.75 for both eyes in 12/2018. However, the prescription for glasses, left eye, was CYL -0.5 from 12/2017 to 5/2020. This is odd: usually prescription for glasses is stronger than for contacts. After 5/2020 my vision was too bad to get a number for astigmatism. It's also curious that the IOL has a positive CYL number (1.5), but the prescriptions I had in past have negative CYL numbers (-0.75 and -0.5). Finally, I remember the surgeon said in early 2021 that my astigmatism is not corneal but lenticular. However, it doesn't make sense to correct lenticular astigmatism using IOL since the original lens is removed. My conclusion is that I have developed a substantial corneal astigmatism in last 12 months.
Beth-R zerlinagirl
Posted
Before my cataract surgeries I wore trifocals and I have an astigmatism. My cataract surgeon told me that I would need to wear glasses due to the astigmatism unless I got the toric lens. I went with the PanOptix Toric lens and spent mucho bucks out of pocket (I understand that is not an option for you). My point is that I understood that if I only corrected using the mono lens I would still be wearing glasses (at that time I was using 4 different sets of glasses for various uses). It might not matter which vision you choose to correct because you might be wearing glasses if it isn't a toric lens. Discuss this with your surgeon, not the technician. Do you know if the mono lens will be a toric lens?
As far as post-surgery, everyone is different. My fancy lenses cause me to see headlights differently, but my brain is adjusting to it, or my eyes have gotten better (1st surgery was December & 2nd was in early February). It can easily take 4-6 months for the vision to settle.
I wish you luck with your decision. Make sure to discuss this fully with your surgeon.
Lynda111 zerlinagirl
Posted
Beth,
I, too, have astigmatism, and I did mention a toric to my surgeon (on two occasions) but she didn't seem that keen about implanting one in me, and I'm not sure I want to do it. I have ptosis (droopy eyelids), which can affect the accuracy of obtaining precise IOL calculations. My cataracts are also dense, and I just want my surgery to as simple as possible for the surgeon and me. Also, I have worn glasses since I was a child (but only one pair) and I am quite used to them, although I have only worn single vision glasses, not progressives or bifocals. Six months seems like a long time for eyes to settle down, but I guess it varies from patient to patient.