Toric IOLs have all the problems of regular IOLs PLUS if they rotate off axis they have to be repositioned or removed. They have the advantage of giving better vision without glasses in an eye with astigmatism.
JCH III MD
From what I have read and heard from other doctors, the toric has a statistically higher chance of having the kinds of problems I've been describing....negative dysphotopsia and other higher order aberrations - glare and halos I think come under that category. It would be good to have this backed here by professional opinion.
What I have been hearing is that the new wavefront technology is offering better lenses, but it is also new technology. Can you wait a year or so before doing surgery? This will give time to see what new technology is available.
With my Toric I choose to have my vision more clear for distance, and it is true that it is more crisp than it was, but it was not really bad to begin with. Sone of the crispness is also from having the fogginess of the cataract removed. My reading distance is not as good as before. I wasn't really thinking, because the small astigmatism I had at 1 diopter was easily fixed with only 1.5 reading glasses from the drug store and I still have to use reading glasses after surgery with the Toric. These are all things to consider for low astigmatism. If I had to do it again I would have done the LRI and gone with a technis aspheric IOL.
How is your vision other than the astigmatism?
Although the Alcon Acrysof toric lens has only been around for about 2 years, there's a silicone toric lens that has been used for at least a decade. The AcrySof toric is reported to provide better vision than the older toric lens because it has less of a tendency to rotate in the eye. In the clinical trials, the AcrySof toric did a significantly better job of correcting astigmatism than limbal relaxing incisions. (I guess it's possible that the surgeons participating in the clinical trials are a more skilled group than other practicing surgeons, which would make the results of the clinical trials uninterpretable.)
From everything I've read, negative dysphotopsia is more common with acrylic (as opposed to silicone) lenses. Laura4, that's why I thought that you'd probably be happier with the silicone version of Tecnis lens, manufactured by AMO. (The Tecnis lens is also made in acrylic.)
Laura4, it sounds like you were myopic before cataract surgery. If your target was good distance vision, it's normal and expected for your distance vision to improve and your close vision to be less sharp post-surgery.
I would have gotten the AcrySof toric lens if it had come in a power sufficient to correct my high myopia. So I got aspheric lenses and LRI's instead, with excellent results. My advice to others would be to choose a skilled and experienced surgeon, get his/her recommendations, and do some research on your own before deciding. It doesn't hurt to get recommendations from more than one surgeon before proceeding.
Thank-you for the helpful information , Dr. Hagen, Laura4 and JodieJ.
Laura4, thanks also for the suggestion to wait for the new technology. Unfortunately, I'm not able to wait very long.
It's pretty challenging right now to work (in an office), drive, cook, etc. with thick glasses that don't correct my vision very well. I'm being extra-cautious (slow) and checking everything 2 or 3 times.
(Also, my right eye vision has been distorted for awhile by an epiretinal membrane - scar tissue resulting from being very myopic. Lately, the left eye has also been more affected - as if I'm looking through finely texturized plastic, sometimes with a white haze as well. Despite this, my eye chart vision is not that bad, R: 20/60 and L: 20/40.)
I'm hoping that, after the cataract surgery, it will be like having contact lenses in my eyes - even though I'm expecting to still wear lighter glasses for both reading and distance actiivities like driving.
Laura4, I think JodieJ is right that it would be normal for you to still need reading glasses if you chose to have your distance vision more clear. I'm making the same choice. It would be so nice to be able to walk around outside without glasses - which wouldn't be possible if I chose to have my close vision more clear. Like you, I'm already in the habit of having a pair of drugstore readers handy for when I sit down to read.
Best of luck to you, Laura4, in deciding what to do - and with the outcome too. Please let us know how you are doing. I'll report back too.
Just want to clarity that I did expect to wear reading glasses post surgery with the Toric. My distance vision was actually fairly good - just a little bit fuzzy. I thought that by clearing up the small amount of astigmatism (1 diopter), the crispness of distance vision would return. At least this was how it was explained to me.
If I did not have the negative dysphotopsia and other higher order aberrations the Toric does create crisp distance vision. If you decide to go with the Toric I hope you do not have these other problems. My surgeon at first said that they were rare, now he says they are quite common.
I'm amazed by the amount of anxiety I have around the vision stress with these complications. As a landscape designer and naturalist (also muscian) my identity and sense of groundedness was very much through my vision - walking, checking out trees and sky. I'll soon be leading an interfaith walk called "Meet the Trees". It's a large event. Last time I focused on a branch in a tree the limbs below it went into double vision. When driving the letters on signs at a specific distance and angle jump in and out of double vision. Almost every day at some point I break down from the stress of it. Actually sent email to 6 eye surgeons at Scheie Institute today. Not giving up.
I also had an epiretinal membrane (a layer of scar tissue causing wrinkling of the macula), so I've done quite a lot of research about this condition. Cataract surgery will absolutely not correct the distortion caused by an ERM. In fact, a multifocal IOL like ReZoom or ReStor will make the distortion MUCH worse. (Check out the remarks of Dr. Michael Wong of Princeton by entering "ReStor IOL intermediate vision woes" in the search feature of this website. His comments appear down the thread.)
You can get a preview of what your post-surgery vision would be like with ReStor/ReZoom by looking thru a RGP multifocal contact lens. Before my retinal surgery, the zones of vision in a multifocal contact interacted with my macular wrinkling to produce one big blur in a eye that could read the 20/50 line with a regular contact.
What is your best corrected vision with glasses alone (no contacts)? This is probably as good as you will get with the best monofocal implants, if everything goes perfectly.
If your ERM is affecting your vision significantly, you might consider having retinal surgery to peel it. This procedure restored the vision in my affected eye to 20/20+ (although I still have some residual distortion.) (Un)fortunately, having a vitrectomy causes a cataract to develop. In my case, this turned out to be a blessing in disguise--the cataract surgery eliminated my high myopia, and my insurance covered the entire bill.
I really don't think that some ophthalmologists understand the disproportionate anxiety that vision problems can create. The double vision that I had for several months (prior to having strabismus surgery) had me so stressed out that it impaired my ability to do simple tasks For example, I had gotten the book-on-tape version of a popular novel from the library, but my concentration was so poor that I couldn't follow the story. The reader might as well have been speaking Urdu--the book just made no sense to me, even after replaying the first tape several times. (The day after my strab surgery, which eliminated my double vision, the book made perfect sense.)
Laura, I think your anxiety is normal, given your symptoms. Hopefully, they will soon be resolved, and you can put an end to this chapter.
I just re-read your post and realize that you're thinking about getting a toric lens rather than ReStor/ReZoom. So scratch my comments--but I do have another concern. I think that having a vitrectomy with ERM peeling might affect your astigmatism, especially if the newer sutureless vitrectomy equipment isn't used. (My astigmatism axis was not the same after retinal surgery.) Maybe you should get an opinion from a retinal surgeon about how this might affect your vision with a toric lens.
I'm gIad that having to wear reading glasses post-cataract surgery was not unexpected for you.
Re-reading your March 16 post, I would just mention that I think reading glasses only correct presbyopia (the far-sightedness that most people get in their 40's), and not astigmatism (irregular curvature of the eye) which is corrected by a toric lens, limbal relaxing incisions, etc. I don't have any special knowledge in this field, as you can see from my posts, so I hope someone will correct me if I'm wrong.
It's helpful to know that your surgeon says that visual aberrations are quite common with toric lenses. That would be a good reason for me to choose an aspheric lens if possible.
I can really identify with your feelings of anxiety. It must be incredibly stressful to try to always carry on calmly, even be a leader of a big event, with double vision jumping out at you. Like you, I'm trying to keep up all my usual activities but it feels overwhelming at times. Even making Easter dinner for family will be difficult and I don't want them to feel my stress. Luckily, my hobby of ballroom dancing doesn't require good vision. Often, I just feel like not going anywhere and not seeing anyone - which is what convinces me that I have to have the surgery and keep searching for solutions - not give up, as you say.
If I have the choice, I will probably ask for an aspheric lens rather than a toric lens to reduce the possibility of visual aberrations - although the aspheric lens my cataract surgeon recommends is the Alcon IQ which is also acrylic. I don't think I could handle aberrations like Laura4 is dealing with on top of the distortions I already have and facing retinal surgery.
I did see my retinal surgeon who said it was fine with him if I have the catarct surgery first. He said that he will likely do an ERM peel of the R eye after cataract surgery has been done on both eyes, but he didn't mention anything about this changing the astigmatism. If he does use the sutureless vitrectomy equipment, does that mean that the ERM peel should not affect the astigmatism?
Do you know whether astigmatism changes a lot from not wearing contact lenses in preparation for cataract surgery? For many years, my astigmatism has been -2.5 in my R eye and none in my L eye. Now, after a few months of not wearing my contacts, I'm told that it is -1.5 in each eye. Perhaps cataract surgeons measure astigmatism differently?
I'm also experiencing slight double vision (strabismus?) which I've mainly noticed when sitting in the dark watching a play - there are two of each person on the stage. So will have to look into that at some point as well.
It's immensely reassuring to me, and I'm sure to Laura4 also, that you've dealt with your vision problems successfully.
My vitrectomy involved sutures, which caused some inflammation before dissolving. The amount of my astigmatism stayed the same post-surgery, but the axis got shifted enough to affect my vision with my old glasses. (I could only see well out of my affected eye if I took the glasses off and twisted them.) I'm guessing that a sutureless vitrectomy would be less likely to affect astigmatism--but it's definitely a question that requires a professional response. (I believe that the astigmatism axis is important with either a toric lens or LRIs.)
Not wearing contacts does indeed affect corneal measurements. The numbers are plugged into a complicated formula used to determine the power of your IOL.
I also have Alcon IQ lenses, and I've never had the type of symptoms that Laura describes. Many retinal surgeons prefer that their patients get acrylic (rather than silicone) lenses--mine did. Because Alcon's toric lens is relatively new, there probably isn't much data available about the incidence of negative dysphotopsia. However, if Laura's doctors state that there is an association, that would be a red flag in my mind.
Thank-you, Jodie. That's very helpful.
I also agree with the red flag in relation to toric lenses based on what Laura's doctors have said.
I saw my 2nd opinion doctor yesterday and I he said that the word aberration - which I've been using - is mostly used with problems following lasek surgery. What I have is negative dysphotopsia (just the dark shadow on temporal side of vision), and positive dysphtopsia (the glare, halos, light flickering) and then the now existing imbalance between eyes which causes some of the wet look. This last part was encouraging since it will be possible to correct the imbalance.
Just trying to improve my technical language here. Dr. John, hope my understanding is correct.
I have one other technical question. If the lowest powered Toric lens has a 1.5 correction, what does that mean for someone with only ,80 diopter of atigmatism. I now have the correct number for my pre surgical astigmatism. That's nothing compared to what Jodie has been describing.
If you have .8 diopter of astigmatism and you put a 1.5 in the eye you will be over corrected by .7 diopter. SO you are not a candidate for a toric IOL. By putting the surgical incision on the steep axis of the cornea, making the incision a little wider than usual and using a lot of steroid eye drops the surgeon should be able to cure about .5 diopters.
JCH III MD
You must be relieved to receive some good news about the feeling of imbalance. I hope it will be helpful to you in deciding whether to replace the toric lens.
With respect to Dr. Hagen's comments about astigmatism, is it possible that measuring this is not an exact matter? I'm wondering this because you might be concerned about possibly being over-corrected.
(The cataract surgeon told me about a week ago that my right eye had 1.5 D. astigmatism but the optometrist said today that it is 2.0 D. However, in my case this could be because retinal scarring makes it difficult for me to answer consistently - when they ask which of two lenses give a better picture.)
What recommendations did the second opinion doctor have for you? Did he know what might be responsible for your dysphotopsia?
The only reason given for both the negative and positive dysphotopsia is the usual answer - it can sometimes happen.
I hope I am understanding the technology of these Toric lenses. I believe there are 3 models in 3 different powers. Mine was the lowest, an SN60T3. If Dr. Hagan is correct, and it's not possible to do more adjustment of the power from the 1.5 of my model than it would be true that I would not medically have been a candidate for even the lowest power Toric. But I still am not sure of my technical understanding. I was also told that a 1.5 would adjust back to a 1.0. Even so, that's crazy if I only had .80 to begin with.
.8 D of astigmatism is very little, and it could have been corrected with a limbal relaxing incision, as Dr. Hagan stated. My technical knowledge about toric lenses is limited, but I remember reading an article someplace about determining which toric lens to use. I'll try to find it again. Would it be possible to safely explant your toric lens?
In early April, I'll see with my cataract surgeon to decide on the type of lens. I would like to ask you a few more questions, if you have time to consider them.
Just to summarize things I've already mentioned:
My prescription is high, pupils are small and astigmatism in my left eye is -1.5 and in my right eye is between -1.5 and -2. I won't be able to wear contact lenses afterwards because of pterygia. Lately, I've been seeing more distortion and a smaller image in my R eye with some double vision - but hopefully this will be improved with an ERM peel after the cataract surgery.
My cataract surgeon has recommended a toric lens because it would correct the astigmatism without LRI and without wearing glasses all the time. He says he has implanted many of them since last year. However, he'd probably be quite willing to use another lens as he says I'm borderline.
In a 2007 post, Jodie mentioned that the aspheric lenses work better with larger pupils and that they improve contrast sensitivity and distance vision. She also mentioned that near and intermediate vision are not as good as with a conventional lens but that was not important to her because she planned to wear multi-focal contacts post-surgery.
Here are my questions:
- Because of my small pupils and inability to wear contacts, do you think I would be better with just a conventional lens rather than an aspheric one?
- With either an aspheric or a conventional lens, I would have LRI or wear glasses all the time. Would LRI be risky for me because of a previous HSV infection?
- If I did get a toric lens, would my small pupils make me less prone to dysphotopsia?
- On the other hand, would my high prescription or other factors make me more prone to it?
- Are there any particular questions I should ask my cataract surgeon?
Thanks very much for reading this long post and for considering my questions.
Naoye, as far as I can determine, Alcon's Acrysof toric iol is still only available in a limited spherical power range (16.0 D to 25.0 D). If you are very myopic and wanting to correct your vision for distance, it is extremely unlikely that anything in this range would work for you. So you might not even be a candidate for the toric lens. (For comparison, I was about -6.75 D and needed a 14.0 D lens--lower numbers correct more myopia.)
Laura4, according to Alcon's toric power calculator, the 1.50 D toric model is supposed to be appropriate for eliminating between .75D and 1.50D of astigmatism. So I guess you were in the range (but barely).