Just wanted to add that, my main goal is to have good distance vision, and intermediate + near vision is a plus. Do I risk having unpredictable GOOD distance vision choosing the Symfony lense verse more predictable GOOD distance vision choosing a monofocal lense?
I'lll provide some input, but I didn't have laser surgery prior to getting the Symfony so I can't comment from personal experience. Here is one article with the results of a small study done on patients with prior LASIK getting the Symfony lens which reports good results:
I suspect the results aren't as good as they could be since both eyes were likely targeted for distance. Studies suggest micro-monovision, targetting one eye just a little nearer than the other, will give better near vision while still leaving at least 20/20 distance vision. That might be difficult to do though with someone with prior laser surgery due to the difficulty accurately selecting the IOL power.
re: "more difficult to predict vision afterwards".
I suspect part of what he is referring to is that choosing the lens power is more difficult in those who had prior laser surgery (especially if they were highly myopic before they did), so there is a chance they might leave you a bit hyperopic or myopic. There isn't an exact formula to determine the power of lens to use, it is based on statistical analysis of the eye measurements of lots of patients and what IOL power would have worked for them. . Choosing the lens power is the same process regardless of the type of lens used (they just plug a different constant or two into the formulas).
One advantage for the Symfony is that its more tolerant to having the wrong lens power chosen (in one direction at least) than a monofocal IOL because it has a larger depth of focus. i.e. if they wind up leaving you even 1.5D hyperopic by accident then you will still have good distance vision with the Symfony, whereas you might not see well enough to drive if you'd gotten a monofocal. If they accidentally left you myopic, then your distance vision would be the same regardless of which lens you had.
Overall distance vision with the Symfony should be comparable to a good monofocal, and if they get the power right you should also have very good intermediate (social&compute distance as well as most household tasks), and a shot at good near.
I've read that doctors are cautious about regular multifocals for patients who have had laser surgery due to concerns over how the irregularities in the cornea will interact with the multifocal. However many will do scans to see how regular the cornea is, and some other tests, to determine if they are candidates despite the prior laser surgery. I think most of the concern is over patients who had laser surgery many years ago and the results may not be as regular as more recent laser surgeries with newer equipment.
The comments I've seen suggest surgeons see the Symfony as a safer option for patients with prior laser surgery than a traditional multifocal. Unless you need really good near vision and would risk the side effects of a multifocal, it seems the Symfony is a better bet.
I do gather that the selecting the right lens power is more difficult in those with prior laser surgery, hopefully your doc is up on the latest research on the issue. I hadn't heard of anyone using him so I don't know how much it costs, , but I remember reading before that one of the experts on IOL power calculations, Dr. Hill, will consult with other surgeons on selecting the lens power, here is his general page on the issue of IOL power selection:
Is this symphony lens a better option than a mono focal lens
Is this symphony lens a better option than a mono focal lens for regulars cataract surgery. This is first time I have heard about these.
I would not choose a multifocal IOL for my eye if I were having surgery. They are more expensive, they are more complication prone, while the optics are better than 5-10 years ago they are not as good as monofocal IOLs. They work best for 'glasses" haters people. While some people are happy with them if you just look at the many posts you will see a lot that are very unhappy.
vmk: I don't know what country you live in, this is a global site and your profile doesn't mention where you are. Unfortunately if you live in the US, the Symfony isn't yet approved here, which is likely why you aren't aware of it. (clinical trial data has been submitted to the FDA apparently, but no one has a good idea how long it might be before approval, I don't know if that means it'll be a year or less or more).
So unless you are able to wait for it or go outside the US (as I did), it isn't an option you need to take time to consider. Its available in Canada, Europe, and much of the rest of the world, but the FDA is notoriously slow to approve new IOLs and often leaves us a few years behind the rest of the world (and some companies don't even bother trying for US approval due to the costs).
The studies that have appeared so far suggest the Symfony has distance vision and a risk of side effects comparable to a good monofocal, with the advantage of having better intermediate&near vision. The downside is mostly that premium lenses cost extra, and that it is a comparatively new lens (first approved in Europe in summer 2014) so there is a slight risk early studies miss something. There is a difference between initial studies and what might turn up when hundreds of thousands of people have used a lens, it is possible the studies miss some rare issues, but of course that means the risk is low you'd experience them because they are rare.
I should note that the doctor commented on multifocals, the Symfony is not a multifocal even if isn't a traditional monofocal either. US based doctors are often not going to be as aware of the details of options like the Symfony since it isn't approved yet in the US. As this article explains, it uses diffractive optics which confuses some people into lumping it into the same category as multifocals, but it isn't the same:
'IOL Alternatives to Multifocality
Avoiding glare and halo while expanding focal depth is the primary goal of these implants.
“The first thing to understand is that the term diffractive optics doesn’t necessarily imply multifocality,” says Daniel Chang, MD, an ophthalmologist from Bakersfield, Calif., who is an investigator for the U.S. trial of the Symfony. “This is not a multifocal lens, but it does use diffractive optics to do two things: First, it corrects chromatic aberration. Second, it uses these optics to extend the range of quality vision.” '
Unfortunately there is no guarantee of the results of any one patient with any lens. Some people have problems with halos even with a monofocal lens, there is no lens yet that doesn't give a small percentage of people problems unfortunately.
This study for FDA approval by Alcon doesn't note the severity of the halos, which can vary greatly, but with one model monofocal Alcon lens that on questioning at 6 months postop 39% report halos, while with the new Alcon +2.5 multifocal 66% report halos, in Table 1:
So even monofocals can cause issues. Unfortunately it doesn't break out the severity of the issues, which is important.
In contrast this data for FDA approval of Tecnis low add multifocals may use a different methodology and shows 4.1% with Tecnis monofocals experiencing halos at 6 months, 20% of the +2.75 multifocal experiencing them and 24.7% of those with the +3.25 multifocal experiencing them, in Table 20:
The main issue though to look at would be the severity of the halos, with for instance 0% of monofocal users reporting severe halos, 0.7% of the +2.75, and 4% of the +3.25 add experiencing them.
Since different studies use different methodologies and have different margins of errors and uncertainties it is hard to compare them. It may be that a larger study shows some % > 0 of Tecnis monofocal users see severe halos. A recent report for the Symfony reports some studies show 0% severe halos for the Symfony, some show a bit higher, but still low (given again that no lens is perfect):
"Visual Symptoms Reported for an Extended Range of Vision IOL Across Multiple Large Clinical Studies...
A total of 737 subjects at 71 clinical sites across the US, Europe and New Zealand were enrolled, implanted and available for a 3‑6 month postoperative assessment. ...
The majority of subjects (89.7% to 100%) across all studies reported none or mild visual symptoms of halo, glare and/or starbursts. Reports of severe halos ranged from 0.0% to 3.1%; severe starburst reports ranged from 0.0% to 1.4% and severe night glare reports ranged from 0.0% to 2.0%. All studies asked if subjects would recommend the TECNIS Symfony®1-Piece IOL to a friend and/or have the same IOL implanted again, with 95% - 99% of all subjects responding “yes.”
Results showed consistently low reports of severe visual symptoms and a high patient satisfaction."
PS, I'll note that the best studies are head to head comparison studies of one lens vs. another that use the same methodology to compare the lenses. It is those head to head studies that report comparable halo and other issues with the Symfony compared to monofocals, and similar contrast sensitivity. The bulk study of Symfony side effect merely notes major issues are rare, it wasn't head to head with a monofocal.
= just means I've read the postings to that point and don't have any further comments to make.
be sure you've have read this article i wrote:
If I were having cataract surgery tomorrow I would have a monofocal toric IOL put in the eye. I would still not consider any multifocal or accommodating IOL. I would expect to wear progressive multifocal glasses after surgery but be able to do many things without the glasses. Because I'm near-sighted and have read all my life without glasses I would chose a mini-monofocal refractive error roughly -2.50 and -1.00 I have about 2.5 diopters of astigmatism which I would hope to eliminate with the toric IOL.
But that is just what I would do and not necessarily best for everyone.
btw, I'll add for desm0nd's benefit that Dr. Hagan is based in the US where other options aren't available.
There is a video from a US expert on IOLs, Douglas Koch who , where he is asked after the 5 minute mark about what IOL he would chose if he had to do so now, and he says he'd likely go have one of his European colleagues implant the Symfony. Unfortunately there is no direct web link, if you go to this site:
and search for Douglas Koch, its the first video. A prior article had quoted him, and a Dr. Donnenfeld who is involved with the US Symfony trials:
"Dr. Koch would like to see peer-reviewed study data to substantiate the results from the AMO studies. Nonetheless, he is excited about the possibilities with these technologies. “I am so impressed by the enthusiasm of the surgeons who have used this lens. This offers the option of micro monovision, giving patients an excellent range of vision without true monovision or other significant visual compromise,” he said....
“My impression is the same as physicians internationally. Patients are enjoying the lens with minimal refractive complaints,” Dr. Donnenfeld said."
Here is a short video from a surgeon that again stresses the difference between EDOF and multifocal lenses, and mentions the issue again of the Symfony being useful if there is a chance the refractive target isn't hit:
Another new article on the Symfony with a US surgeon noting:
"As a member of the advisory board that first reviewed this lens, I was intrigued by what I learned about the optics. In fact, my initial reaction was that the Symfony is an IOL that I would consider for my own eye—the first time I have felt that way about any presbyopia-correcting technology. It was also appealing to me that only the optics were changed. The lens material, spherical aberration properties, haptic design, implantation technique, and other attributes of the Symfony are identical to those of Tecnis one-piece IOLs."