Extended Depth of Focus (EDOF) vs. Trifocal intraocular lenses (IOL) and confusing lens choices
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Hi all,
BACKGROUND
I am a middle aged guy in his 50s with Dysfunctional Lens Syndrome (DLS). I have had enough of glasses as they are the bane of my existence and have given me never ending grief.
I am sad to admit it, but I am clumsy. I sit on them, bend them, lose them, break them etc. With humidity and my excessive sweating, the damned things fall off my face into my food, onto the floor etc.
The last few years (thanks to high dose Prednisolone corticosteroid for an inflammatory ear disease and its hideous multiple side effects) I have suffered more rapid worsening of vision quality. Only in beginning of 2018 I had near perfect distance vision and only needed glasses for reading.
I now have progressive lens glasses to help with near to distance vision (although I feel more comfortable not wearing glasses for driving and outdoor activities). And they just do not seem to last long before I need to get new scripts to adjust the lens. Has been getting expensive. I am in Thailand stuck here for the foreseeable future because of COVID and am wearing bent frame glasses with one lens that is scratched and a chunk of glass missing LOL.
TWO SURGEON RECOMMENDATIONS - LISA & LENTIS
I saw two separate opthamologist eye surgeons recently here in Thailand. They have both concluded I have DLS after eye examinations. The very beginning of cataracts it seems.
My family has a history of caratacts so it is basically set in stone.
As such the surgeons assessed me for the suitability of intraocular lens replacement surgery. They asked me questions about my lifestyle to assess the type of IOL implant most suitable for me.
Usual day to day living:
- Reading - computers, phone - several hours per day (close to mid distance)
- Activities - walking, jogging, gym workouts, treadmill, cardio (close to mid distance for safety - hand/eye coordination)
- Driving - day and night time, with night driving limited to short trips (since I am currently medically retired). Motorbike riding (close to mid to far distance)
- Other activities - evening socialising indoor and outdoor settings, cooking, shopping etc (variations of mid to far distance)
- Watch TV about 2-3 hours or more per evening (mid distance)
- I enjoy star gazing, sky viewing, landscapes (would appreciate strong black contracts as opposed to hazy)
The first surgeon recommended a trifocal intraocular lens (IOL) from Carl Zeiss manufacturer named 'AT LISA'. Version 839MP
He claimed it meant I would no longer need glasses as I would be able to read up close, computer, TV, drive.
The downside he explained was the 'halo' effect that it can cause at night (I also read starbust, glare as well) and that unless the patient was well prepared and learned to accept and ignore it, then it could cause problems adapting to it. He explained neural adaptation being a very important part of the process.
He explained that depending on the patient, it could be weeks to months or more before you can adapt well enough to function at night (such as driving) and that over time the brain will largely ignore the visual disturbances. He claimed that for the vast majority of patients, they adapted well enough to the point of not even noticing the issues and were extremely happy with the outcomes.
The second specialist I saw at another eye clinic had a different opinion about the type of IOL lens that he prefers to recommend to his patients. He claimed that the main issue with trifocal IOL lenses was the visual disturbances at night/low light.
His recommendation was the 'LENTIS' multifocal lens (by Oculentis). He claims that with improved technology, the issue with night glare, halo etc. had been vastly improved. The trade off he explained in comparison to the LISA trifocal IOL, was that the LENTIS was a mid-strength IOL.
I later researched the LENTIS lens and realised that there are several models of the LENTIS IOL. I am not sure which one he was referring to at this time.
THE TWO MAIN CHOICES OF IOL FOR MULTIFOCALS - THE TRIFOCAL AND EDOF
After an exhaustive night of reading online, watching YOUTUBE videos, I have realised that the IOL world is complex and has a vast selection of choice.
I have learnt that there appears to be two main choices of IOL lenses for those who wish to be glasses free and have relied on progressive/multifocal glasses.
The two are the trifocal IOL and the Extended Depth of Focus (EDOF) IOL.
From what I can understand the main Pros and Cons for each are (forgive me as I know there are several others that may be considered as main points):
Trifocal:
Pros - close-up reading possible. Strong mid distance and long distance focus.
Cons -
i) Distance in-between the close up to the set mid distance focused point is blurred. The distance in-between the mid distance point to the set far distance focus point is blurred. This would necessitate at times the need to move your body within the range of the focus points that the trifocal IOL three-focal point distance settings are are, so as to see clearly.
ii) Night time visual disturbances (as well as low light). Halos, starburst and increased glare effect.
iii) Out of focus vision other than for the one of three focal points that you are adjusted to.
EDOF:
Pros -
i) greater range of focus from near vision to distance, without gaps that are blurred like tri-focal IOLs. A smoother transition from near to far objects.
ii) Significantly reduced night vision anomalies such as the halos, starburst and glaze issues
Cons -
i) Close-up vision begins at a greater distance than trifocal lens. This may necessitate the need for reading glasses for close-up work.
ii) The points of focus ranges where the trifocal lenses cover are not as clear as the trifocal IOLs.
There are other things I have not included as I became overwhelmed. The trifocals and EDOF also seem to perhaps have varying advantages/disadvantages in regards to contrast, colours, haziness. These additional points were further muddled with different brands and models of IOLs having different advantage/disadvantages.
And each IOL is on the spectrum on or somewhere in-between the refractive and diffractive range too (Google search - Refractive Multi Focal Intraocular Lenses provide better intermediate vision and diffractive slightly better near vision and less haloes and glare).
Adding another layer of confusion is the definition of EDOF. The FDA has not apparently adopted a strict EDOF definition. So, certain IOL manufacturers appear to claim their lenses are EDOF IOLs when in fact they are really only trifocal IOLs with a closer stacked visual range to look like EDOF IOLs.
(I truly recommend the YouTube Channel titled 'Eye surgery explained' that is run by a guy that truly seems to have a very in depth knowledge of intraocular lenses and the IOL industry tricks. Downside is that I have suffered information overload.)
At the night's end (about 3am) I had a whopping headache and overwhelmed. From what I thought was a relatively straight forward thing ( mutlifocal IOL implant) has turned into a minefield. I am now unsure as to what to do.
I want it all - close up 'glasses free' vision and the progressive smooth focus from near to far, deep contrasts, vivid colours, true blacks, no haziness, no night time visual disturbances, and a focus that is constantly crisp and sharp through all depths of field. Reality is it seems, you cannot have it all and there is no free lunch. I just don't know what to compromise.
I was close to booking the first surgeon there and then after he showed me a view of how my lenses may look like. But after the second surgeon's consultation and his opinion, I am very indecisive.
I would love to hear from the IOL community and their experiences. Any help to assist me (and perhaps others) in this significant choice would be greatly appreciated.
1 like, 23 replies
rwbil Peter81761
Edited
I will tell you my story.
I have the Tecnis Low Add MF +2.75 in my left eye and my natural lens in my right eye (At the time neither EDOF or Trifocals were FDA approved). I plan to get the Tecnis Synergy implanted for my other eye this year.
This means I get dysphotopsias. But the trade-off is worth it to me. I get Functional Close. What that means is I can see a menu in a restaurant or read a label at a grocery store. And yea if I find the right sweet spot I can read an article, but to do any serious reading I need a good light and readers.
I want to comment on neural adaptation
I read someone else explanation of what really happens and it was so much better than how I would have explained it I will paste their words and it also applies to defractive EDOF IOLs:
“To be clear, multifocal visual disturbances never "go away". You can't change physics. A more accurate thing to say is that the brain habituates to them. The visual disturbances are still there and if you THINK about it you will see then exactly the same as you always have. It's just that if your DON'T think about it you don't notice it. You brain learns to "filter them out". But they're still there.”
Now I will add to that. Everyone is different and everyone comes into this with different eye conditions. And that is the problems, as you will never know or be able to predict your outcome until after surgery.
One final note there is more to the story than just dysphotopsias. I am choosing the Synergy over the Trifocal, because hopefully there is less splitting of the light. BTW I am still research that one. I need additional light in certain circumstances. And I will tell you a true story to give you an idea. I was walking down my steps at night and then my natural eye itched, so I scratched it, thus covering that eye and wam bam I could not see the steps using my MF eye along. So realize this going in.
I will also give you a real-word dysphotopsias story I am experiencing right now. I am currently out of town and this city has these old timey light post, I have never seen in my city. And damn I get these huge starburst off them. Actually I think they are kind of cool looking. But it just points out you have to think of dysphotopsias to where you live and your life style. If you live in a dense city with lots of lights and drive a lot at night your experience may very well be quite different from me who lives in the boring suburbs.
If you have any questions feel free to ask.
Peter81761 rwbil
Posted
Thanks for relaying your experience. I actually get slight starburst and glare already, without glasses and have no implants. They do not bother me so far, except when there is heavy traffic and I have to squint to navigate. I only thought about it recently after researching dysphotopsia.
I am in a town saturated in light at night as it is a tourist sea side town. Hot and humid daytime weather means staying out later in the evening and being exposed to lights. I am more prone to living in city and towns with night lighting. I ride a motorbike at night most days for quick trips of 5 to 10 minutes each way. And drive as well. I go out maybe twice a week in the evenings.
So, dysphotopsia is something that, if I chose trifocal or EDOF, I need to be able to adapt to .
But, I do use my laptop and mobile handset a lot at home and out and about. Also, daily things like reading menus, shopping and reading labels on products and price tags with fine print, has always been a struggle.
I need to wear a 'bumbag' everywhere to lug my glasses about as they bend and break in my pockets (have done this several times). It would be great to one day only need my trouser or shorts pockets to carry my wallet and keys! Neck cords do not work for me.
I am in a hot humid environment where daily attire is shorts and t-shirt/tank tops usually. A cold or cooler climate would allow more suitable attire with shirt/jacket pockets to accommodate glasses. Alas, I am not in such a place and I am retired. Hence my keenness on strong focal lenses as well that a trifocal IOL would provide.
RonAKA Peter81761
Edited
With my monofocal IOL and simulated monovision with a contact lens I have no trouble driving at night in the city. The street lighting is a big help in seeing well, and with the monofocal I have no dysphotopsia. I would not be nearly as confident driving in the country at night with no street lighting, and would probably use my progressive glasses instead.
.
However, during the day and in the city I never take glasses with me. Yes, occasionally in a drug store I may get caught being unable to read some super fine print, but for normal shopping etc. I don't bother with glasses.
RonAKA Peter81761
Edited
Oh, and I ride a motorcycle. The monovision has been the biggest benefit there. I use a full coverage tight fitting helmet and it has always been a major pain to get my glasses inside the helmet and over my ears. Now, I don't need them. I see the instruments fine and in distance fine with no glasses.
rwbil Peter81761
Edited
"I need to wear a 'bumbag' everywhere to lug my glasses about...."
I can so relate. I had so many reading glasses. I even had the pair that connects via magnets and I constantly got comments by people that my reader's were broken.
Yet with all the readers I never had one when I needed one.
The problems is you just have no idea how any individual's dysphotopsias will be. My advice is if you have any type of serious or even borderline serious eye condition go with a monofocal.
Luckily my dysphtopsias are mild and well worth the tradeoff. I am more bothered by the splitting of the light and just how dark that IOL is at night. Supposedly Synergy splits the light less.
I am waiting for my doctor to get more Synergy implants under his belt and give me feedback on what his patients results are.
Peter81761
Edited
I have just read up on another IOL called 'MEDICEM WIOL-CF Accommodative Polyfocal IOL', that works similarly to a natural lens and shaped the same. Reading the information, it covers all range of distance from near to far, with the only need for glasses for fine near vision. But there does seem to be less ability to accomodate in older age and hence focus as well. Not sure what that translates to in respect to these types of lenses working.
It appears to solve the low light and contrast issues as well as dysphotopsia issues. I am in Thailand and not sure if or who would use this IOL and if it is even approved here.
But from reading it, this lens seems to be much closer to what an artificial lens should be like, compared to the flat lens and concentric rings on trifocals and EDOF IOLs.
https://swissmed.asia/shop/intra-ocular-lenses/medicem-wiol-cf-accommodative-polyfocal-iol/
Anyone heard of this?
giles89925 Peter81761
Edited
Hello,
I don't know if this helps or makes things more difficult. I was on this forum a while ago trying to make the same sort of decision as you. I had pretty much decided to go with the AT Lisa, when the pandemic hit and cataract operations were halted (in the UK). I used this to reconsider my options, as I had also wanted to find a way to avoid glasses.
During this time, my surgeon retired and passed my files to a colleague - I know someone who works in their practice and so I have now managed to get the 'free' opinion of five surgeons in addition to the original. Four of the five said they would never choose anything for themselves other than a monofocal. The various reasons they gave ranged across: night-time glare and halos, as pretty much a certainty; loss of contrast sensitivity, particularly in low light; no guarantee that you will avoid glasses; less clarity and less 'quality of vision' - this last one confused me because when I brought up the studies that show comparable results, they said that with trifocals or EDoF lenses you find that the clarity is not as good, and that while you may have very good scores using an eye-chart this doesn't necessarily transfer to daily living. The one surgeon who was happy to use trifocals agreed with all of this, but said that after having cataracts all lenses were an improvement. (Which is not really a ringing endorsement.)
So, now I find myself leaning more towards the monofocal - to add to the confusion both my brother and a good friend had monofocals implanted just before the pandemic, and both are really happy with the outcome. In fact, only today my brother's surgeon actually told him he made the right choice going for a monofocal due to the number of trifocals she has explanted.
Of course, everyone's experience and needs are different and I believe that all the lenses are probably very good in the right situation. I don't want to take away from any of the forum members who have recommended other lenses, some of whom were very generous with advice to me early on - but I do think it is worth noting how many eye doctors - in my limited circle - think that the potential benefits are not worth the potential downsides.
Anyway, long post to say that it might be worth considering the monofocals - and I say this as someone who desperately wanted the trifocals to be the right choice for me.
assia99778 Peter81761
Posted
Hello Peter,
did you make a decision in the meantime?
I have trifocal ZEISS LISA in both eyes. Surgery was one year ago. Didn't wear glasses since childhood (contacts only) but now have to wear several pairs of glasses all the time. In addition severe dysphotopsia which means huge contric rings and spider webs around point light sources that impair my night driving ability. They didn't decline. Glare even increased. I got floaters because of the surgery and other unwanted issues. One should know that in 73% of the cases they don't hit the refractive target. I am one of those 73% with significant residual astigmatism left in both eyes. If you don't need toric IOLs, than it's easier because rotation of the lenses does not apply to you. Despite second surgery with rerotation both IOL are still off-axis. Maybe this also increases my dysphotopsia. Laser treatment won't help with this. The refraction error can be fully corrected with glasses but with laser it's unsure. In addition laser will cause dry eyes. My eyes have already suffered from the surgeries. Contacts are therefore no longer possible.
The ZEISS lens is not good for demanding computer work because it has deficiencies in the intermediate range. The lens also doesn't provide seemless vision, there are gaps. In my case I need +1 reading glasses for laptop work and +2 reading glasses for closer reading and handwriting. Be aware that varifocals are not possible after receiving trifocal lens implants. Therefore I have to put the reading glasses on top of my far specs which I need to correct the residual astigmatism.
Of course you can be happy with your outcome but refractive surprises can always occur. Diffractive optics means dyshotopsia, it's physics. But they differ individually in size and brightness. You will loose contrast. To give you an example what this means: Before the surgery I was able to read the street names on the other of the road (4 lanes) while driving at night in the city. That's no longer possible.
So far my experience.