Now that the Symfony IOL has been approved by the FDA for use in the USA, does anyone know when it will be actually available, and/or what US cataract surgeons have experience using it?
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I may be getting a symphony IOL for my right eye here in Pune, India. This lens seems to be common place in India. It is going to cost Rs. 60,000. ( slightly less than 1000 $ US).
re: "it's that question of does it go from clear to blurry fast"
That is the difference between a monofocal and the Symfony, the monofocal gets blurry much faster than the Symfony, the range of good vision is smaller. The range outwards from the best focus is about the same in both cases (e.g. if the best focus is set at 10 feet, the vision further out would be about the same with a Symfony and a monofocal, and it still might actually be 20/20 for far distance). Unfortunately the studies only give average values, some people have better or worse results, but the studies give some clue what might work.
It is difficult to know what the various numbers like 20/40 translate to in terms of visual quality, but this site I found lists the print sizes you can see for various levels of vision at near, which suggests e.g. 20/40 isn't bad:
http://www.teachingvisuallyimpaired.com/print-comparisons.html
For instance if you had an eye set to focus at far distance with a monofocal, then according to info on the Tecnis website:
http://www.tecnisiol.com/eu/tecnis-symfony-iol.htm
with their monofocal your vision would have dropped to almost 20/40 by around -1.5D = 66 cm = about 26 inches, whereas with the Symfony it wouldn't drop that far down until about -2.5D = 40 cm = about 15.7 inches. With a slight bit of monovision, you might be able to have one eye set just a little bit closer in and be able to hit your "one foot" mark with the Symfony while still having great distance vision.
10 feet is about 305 centimeters. The formula for determining the diopters required for a particular focal point is -(100 / distance_in_centimeters) so that would be focused at -0.33D. So one eye could be focused there (giving you perhaps 20/20 still at far distance) or at perhaps -0.5D or -0.75D (since you get good vision a little further our).
1 foot is about 30.5 centimeters, so that would a focal point of -3.3D. If you had 1 eye set at -1D with the Symfony, that would give you better than 20/40 vision at 1 foot, -1.5D with the Symfony would give you better than 20/30 still at 1 foot, or if you had it set at -2D that would give you 20/20 vision still at 1 foot. The level of difference between the two eyes would impact how much loss of stereopsis (3D binocular vision) you had. The level of monovision required would be less than with a regular monofocal. Unfortunately again those are average study results, so to play it safe you might wish to have one eye set a bit further in than you need.
thanks for the input. as i work as a hair stylist/barber my need for best vision is in the "foot to ten feet" range-- or close enough for a good men's hair cut and out to the mirror and back.... i have worn didstance glasses since 9, so that's not an issue, i'd be fine still wearing them. it's that quesiton of does it go from clear to blurry fast or is there that 'range' where like normally, it just gets blurry from the distance? if the makes sense. the monofocals sound like it's "focus at one foot and anything 13 inches and out or in is blurred" or "get good distance, but trying to see the dashboard while driving is like looking trough wax paper.... that depth of focus and binocular vision loss...
The lenses come in different powers, just like glasses or contacts. You'll see discussion on this site and elsewhere of people getting monofocals where there best focal point is set for intermediate or near instead of for distance. The same can be done for the Symfony. The difference is that if you had the Symfony and a monofocal both set to the same best focal point (whether intermediate or distance), that the Symfony will give you a wider range of clear vision, you will be able to see well closer in with the Symfony than a monofocal by a diopter or so (unfortunately that isn't a fixed distance in inches or centimeters, the distance a diopter translates to is different depending on where the focal point starts).
re: "then to find someone versed enough to to the surgery"
Any competent surgeon will be able to do the surgery with the Symfony since the procedure to implant it is the same as other IOLs. The lens material and the overall lens shape and size is the same as the widely used Tecnis monofocal and multifocals currently available in the US. The only difference is the optics of the lens, which doesn't matter to the surgeon implanting the lens. The only issue that might be new to them is helping you decide where to put the best focal point because of the fact that it does have a wider range of good vision than a monofocal, but that is a simple matter they can understand from looking at the defocus charts and data.
re: " "liquid vision" lens to be out sooner for better"
The next generation accommodating lenses are a ways away from approval in the US. The only one I'd heard trying for approval anywhere is the Lumina which is reportedly trying for approval in Europe, trying to get a CE Mark (their equivalent of FDA approval). I haven't seen any estimate as to when that might happen, and after it does it'd likely be quite a while before its approved in the US. More importantly, I'd suggest caution before considering using a next generation accommodating lens until they've been widely used in human eyes. Their functioning relies on the eye's accommodation mechanism, which means that the only way to test them well is with humans. They need to be sure not only that the lenses move properly, but that all the movement doesn't lead to problems over time (e.g. the lens moving out of position, some bad interaction over time physically wearing out part of the eye through its movements, or whatever other complications might arise when there are moving parts at work). The new accommodating lenses are also often different sizes, shapes and materials compared to existing lenses, so any issues that might arise from that need to be tested.
Static lenses that don't need to move or change shape (like the Symfony, monofocals, and multifocals) only differ in their optics, which can be well tested on optical benches outside of the eye. The major issue they need to test for in human eyes are subjective factors like halo&glare, which can be done well with fairly small clinical trials.
The Synchrony lens was an accommodating lens that showed promise, but seems to be off the market (or at least not used by anyone) due to a sizeable minority having problems (one of the posters on this site, AnomalyChick, got the Synchrony lens in Europe). I tend to be an early adopter of technology, but someone who tries to take educated risks and I'd personally be cautious to ensure a new accommodating lens was used a fair amount before I risked it, but everyone's risk tolerance is different. The issue would be to figure out what the potential risks are, e.g. if you did need a lens exchange from an accommodating lens due to problems, would there be a greater risk that the capsule might be damaged, which would limit the sort of replacement lens you could get (since most premium lenses are for placement in the capsule).
I'd originally hoped I might wait for an accommodating lens, but I later realized that I'd have been more cautious about it than a new static lens like a new extended depth of focus design or a trifocal.
just wondering -- i have cataract in rt eye caused by a vitrectomy from another issue so am "looking forward" to surgery to replace lens. trying to wait till symfony is approved in the US (sounds like 2017 or earlier now)
question
do they come in different "flavors" or strengths? i.e. can it be set for more close/intermediate rather than intermediate/far? i have worn distance glasses since grad school and have no issue with continuing-- but i need far more close and intermediate clear vision for work and hobbies.
how do they set the extended depth of focus?
i really hope they get approved in the US soon. and then to find someone versed enough to to the surgery.
i was hoping for the "liquid vision" lens to be out sooner for better but this seems the best current solution and as it's the non dominant eye less strict?
in L.A. area