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Tecnis monofocal iol and flickering/flashing light

Good evening everyone,
I'm almost 40 years old, had cataract surgery a week ago on the left eye, monofocal tecnis 1-piece IOL (ZCB00). I have a very irregular corneal astigmatism so a toric lens was too much of a risk.
Now I am surprisingly reading well without glasses and I can see relatively well far too. Am very pleased with my functional side, very small halos around some lights at night.
But there is something VERY ANNOYING that worries me–during the day, when the sunlight comes into the house through window, usually at my side, my eye experiences a very strong flickering of light, like a strobe-effect in my eye (more around my eyes than central). I read about eyes movement named saccades and it looks like these movements causes that flashing for every movement. I read this fine iol has frosted edge to prevent such problems... so what could be the reason for that?
Hope anyone can help me. Best wishes
2 Responses
177275 tn?1511755244
In most instances that is a reflex arising from he incision made into the cornea.  It is different from negative and positive dysphotopsia. My wife had surgery with a tecnis monofocal IOL 3 weeks ago. she noted immediately under certain lighting situations. It has gotten much better as do most of these cases. When you see it rearrange yourself so light does not enter you eye at that angle.
thank you, Sir! it's indeed very interesting what you say and probably it's related to that too, but such flashing I'm experiencing is caused by lighting from above as wel. The worst mix is strong sunlight from the window and artificial lighting from the ceiling, it drives me crazy because my eye starts flickering at each small eye movement.
Discuss it with your surgeon. Highly likely will diminish over coming weeks. you have a first class IOL in your eye. As I said not an uncommon observation in the first 1-4 wks post operative.
I hope so. But this is also a common observation in patient with multifocal iol after many months.
I read that tecnis one-piece acrylic has frosted edge, so this would help to reduce such dysphotopsias. But it's still a squared edge. The 3-piece silicone Tecnis has frosted edge but squared only the posterior side to prevent cell proliferation, rounded the anterior. Maybe he surgeon should have used this silicone lens in my case. What's actually the difference between the two lenses?
The multifocal IOLs generate their own abberant unwanted light reflexes (dysphotopsia-something I have written on before) So it persists. In the short term light areas seen immediately after surgery often come from light bent (diffracted) by the one or two surgical incisions.  So wound related light reflexes get better because the swelling in the wound goes down and the scar gets smaller and lighter.  I don't want to do any critiques of IOL technology.  No company would market an IOL that they thought had any properties that would hurt sales.  That has not always been the case (think ReZoom and Azar 91-Z and stableflex IOLs).
Doctor Hagan, may I ask what is the difference between dysphotopsia of a monofocal iol and a multifocal iol?
The symptom is the same. unwanted light reflexes from an optical system (can also occur from human lens, cornea, camera, any optical symptom. It is a form of optical aberration with clinical implication.   The type of immediate wavy light colored spots usually comes from the cornea incision and goes away. The dypshotopsia can be a dark area ("temporal darkness") or "light colored' "positive dys."   There is much unknown why it occurs. You can pull up extended scholarly reviews easily on the internet by physicians that deal with this.  The edge of the IOL was felt to be the primary cause in monofocal IOLS but these have been modified mainly by removing sharp edges.  the % of people with persistent troubling dysphotopsia with monofocal IOLs is very low perhaps 0.25% as a clinical guess.  Somewhat higher with toric IOLs due to off axis orientation.  Much higher with multifocal IOLs because its not so much the edge as the rings on the IOL optic that cause. Less common with accommodating IOLs like Crystalens.  Better with newer multifocal IOLS but if you look you will see more and more posts from the newly released Symfony IOL.
Thank you for your help! My lens is Tecnis one-piece (ZKB00) and it DOES NOT have rounded edges but squared on both side. The 3-piece silicone Tecnis (Z9002) does have one side rounded. What exact Tecnis model was implanted in your wife's eye, if I may ask?
Tecnis Model ZA9003 which is the standard IOL our practice uses for monofocal IOLs. We also use Tecnis Torics.  my wife has astigmatism but we did not opt for toric as she wanted to keep it simple, does not mind glasses. We also passed on femtosecond laser and ORA technology    Your IOL is a multifocal IOL not a monofocal if it is a ZKBOO   If ZCB00 as you posted first time is a new one piece monofocal.
Sorry, my IOL is TECNIS Monofocal 1-Piece IOL (ZCB00).
I see, so your wife has a silicone with one side rounded and one squared, my lens is acrylic, both sides squared.
I'm afraid my light disturbances are due to the both squared edge of the ZCB00 ...
Not sure why my surgeon opted for the one-piece monofocal ... What's the difference between the two lenses?
You would have to look at their website.  Very frankly very few people have problems with modern monofocal IOLs.   I doubt you have problems 6 weeks from now.  It is not possible to carry an inventory of every type of IOL and let people choose like ordering food from a menu.  
Of course, but it's also true that, as you said, some people may have dysphotopsia problems even with monofocal iols, maybe people with corneal diseases, or had lasik in the past or have large pupils. Also silicone and acrylic have not the same effect on every eye. I have a deeply annoying flashing in my eye with this lens and I read on forums that there are several people (not few, many!) with the same problem, even after several months or a year.
Okay I've added what information I can. Best of luck
hi, did the window problem dissapeared ?
Last post was Jan 18. Might hunt that up. you can also leave a note for him on home page
Hello teknis, I realize your post was quite a while back, but I have a pretty good idea what your problem is (or was) so I am wondering if you were able to get some relief from it. If not, try to duplicate the most egregious conditions whereby you have this problem. I would suggest the brightly lit room with sunlight from above and or to the side. You will need a modestly complex scene in front of you with a lot of contrast (dark objects, light objects, etc.). Your living room would probably work fine. Looking straight ahead, move both eyes rapidly up and down. Repeat while covering your right eye. If this causes a significant change (for the better), then your problem is the that your lens is "bouncing" so to speak or moving very rapidly and settling back in.

If I am correct on this, you are seeing broad flashing/shadows that is/are not really flashing at all but your brain trying to resolve instantaneous conflicting images, possibly only lasting for 50 msec with each eye movement.

If you could paint your living room green from floor to ceiling (for example) you wouldn't see this wholesale problem (nothing for your brain to work on here), but you might notice some actual flashing more in the periphery that would match the frequency of what you are calling flashing in the main part of your vision.  If this all makes sense to you and generally seems to explain what you see, then I have another experiment that you can do in the dark that will add to the evidence you will need when talking to your surgeon.
177275 tn?1511755244
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177275 tn?1511755244
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