UPDATES + Preliminary verdict on Mini Mono-Vision.

You said your wife's target for the distance eye was -0.25 D, and -1.50 D for the nearer focus eye. Does this mean that to correct the distance eye (now with the IOL in place) to perfect distance vision a -0.25 D lens would have to be used? Like eyeglasses? Similar for the close eye, it would now need a -1.50 D eyeglass lens to be fully corrected for distance?

.

Yes something like that. The eye doc said recently that -0.25 far right eye combined with astigmatism of -0.75 now (pre OP was approximately -0.35) means if she decides to use contact lens to get right far eye to perfect plano might require a .5 diopter strength correction or .25 diopter correction might be enough too. Will have to see based on measurements at the contact lens specialist. We are not planning that currently as she functions very well. Will let the tear film recover for few more months anyway before introducing more variables.

.

Yes you could correct -1.5 eye to plano too but that would defeat the purpose of mini monovision 😃 I guess you mean for driving having both eyes for plano?

My question is only about how one can relate what we see with contacts monovision to IOL monovision. More specifically if I try contacts with my intended reading eye undercorrected by -1.25, is that going to give me an idea what IOL monovision of -1.25 anisometropia would look like. Some years ago I tried contacts with -1.25 anisometropia and it was pretty good. Wondering if I do the contact anisometropia again, how indicitive it would be of what I would see with IOLs?

Yes it would "roughly" give you an idea. The plane where IOL sits although is not same as where contact lens or glasses sit. Every micro mm that the IOL moves has a big impact on the refractive outcome. Some of the surgeons we met were themselves wearing mini monovision glasses.

"Anisometropia is when two eyes have unequal refractive power. Generally a difference in power of two diopters or more is the accepted threshold to label the condition anisometropia."

Under 2 diopter your brain should have absolutely no problems ( generally speaking). My wife adapted almost instantly to even 3 diopter difference. Although she did mention that she was getting 3d effect initially.

Thank you for your further advice. What I am trying to do is relate the various studies on the optimum amount of anisometropia for a monovision strategy. There are obvious competing issues with more and less, but at the end of the day unless one goes with a multifocal solution in the reading eye, there can only be one number when the rubber hits the road.

.

My observation is that there is a trend over time to use less and less anisometropia. In the past up to -2.75 has been used with monovision, but today as little as -0.5 is used. The other thing I have observed is that more and more attention is being paid to the age of the user and the maximum size of the pupil, which of course are related. It seems that the smaller the pupil size the more tolerant users are of less anisometropia. This would suggest a younger person like your wife in the early forties is going to need more anisometropia and be less tolerant of a smaller amount.

As I am just past 70, my thinking is that I should be looking at the lower end of the range of anisometropia to get an optimum outcome. What I am targeting is eyeglass independence down to the computer reading range, but am willing to accept eyeglass correction for small print. In fact I think at the end of the day, I will probably end up with prescription progressives that give me small print ability in both eyes, full distance correction in both eyes, and correction of any residual astigmatism after IOL surgery. I would use these glasses for reading small print and driving at night. Since I seldom read small print and try to avoid driving at night, use would be very minimal...

In case you were curious...

My wife's left near eye has pupil size of 6.26mm. This -1.5 eye sees tiniest of text sharp on labels etc. The smallest paragraph on near eye test chart and obviously without any glasses.

.

The far -0.25 eye has pupil size of 5.94mm.

.

The white to white on both eyes is approximately 12.10mm

.

This would suggest a younger person like your wife in the early forties is going to need more anisometropia and be less tolerant of a smaller amount.

Do you mean from point of view of being glasses independent?

.

The greater the diopter difference between the two eyes, the greater the brain has to work to combine the images, irrespective of age. It is another thing that brain is super smart in lot of cases and does the work easily.

.

All brains will adapt to small difference but not all brains will adapt to large difference ( I mean anything from 1 diopter difference to under 3 diopter difference can get tricky for some people).

Forgot another point..

As I am just past 70, my thinking is that I should be looking at the lower end of the range of anisometropia to get an optimum outcome.

Aiming for -1 to -1.5 final diopter difference between the two eyes would be a safe way to go. It will depend anyway on IOL power availability for your eye + IOL combination etc.

Your wife's experience is very helpful to me. My previous monovision experience with contacts was with -1.25 anisometropia. I did not find that disturbing, but I did find reading fine print for example on medications at a drug store difficult. I recall on at least one occasion having to use reading glasses off the shelf to read the labels.

My thinking based on some research is that as I am now older, and much older than your wife, my maximum pupil size is reduced, and that is not all bad. As the pupil size reduces the depth of field of vision increases. I think that allows me to get away with less anisometropia, which in turn will reduce the impact of anisometropia on intermediate and distance vision in the near eye. My thoughts are that I want to use as little as possible but still see my computer screen clearly. If I get to read smaller print like your wife can, that would be a big bonus. Based on charts like this one, I am thinking my max pupil size is just under 4 mm.

Then another report (Assessment of Differences in Pupil Size Following Phacoemulsification Surgery) I read suggests that pupil size is reduced following Phacoemulsification Surgery by about 20%:

That would bring me down to the 3 mm range for pupil size, and probably able to tolerate a smaller degree of anisometropia. Your estimation earlier your thread on the surgeon's ability to predict outcomes was in the +/- 0.5 D range is scary. I was hoping for much better accuracy than that.... In any case my thinking now with that risk of inaccuracy and my smaller pupil size, is that I should be asking for a residual anisometropia of -1.0 to -1.25, and hope they can actually hit that range. Does that sound reasonable?

I think I can explain why the targets are a little unpredictable. the IOLs for most part come in increments of .50 diopters vs .25 like glasses or contact lenses. Added to that IOLs are just 1mm thick vs 4mm of our natural lens. Depending were IOL settles during healing process you could be +- .50D

Surgeons take all that into consideration and rarely aim for plano - people are better off slightly under corrected than over corrected.

Also that is why it is never a good idea to have the surgeries too close together. Once first eye's surgery has settled (4 to 6 weeks) adjustments can be made to 2nd eye.

Yes, the coarse power increments of the IOLs are a limitation, but it would seem if your required power falls right in the middle of two sizes that would be the maximum error, of 0.25 D. I had thought when I found out I didn't need a toric lens that the lens position would become less critical. However, that is a good point. If the lens moves forward and back that would change the power, with being off centre not helpful either. I guess it would pay to have a lens that stays put and does not move from the position the surgeon puts it in.

It is always a gamble where the lens settles, Sue is as usual right 😃

The cataracts makes the lens even bigger than the lens was before, and the iol is in any case a lot thinner than the natural lens, so the surgeon have to "guess" where the iol will settle, and this can shift during the healing period no matter what iol is used, it can easily move the outcome by 0.5 diopter or more.

And beside that measurements can never be 100% precise, there are different measurement techniques, and they often do not get the same result, some surgeons uses more than one technique, and then uses his/hers experience to choose the right lens.

In some cases it can be really difficult to get any measurements at all if the cataracts are dense.

In my case they took several measurements, and discarded some of them, but some seemed to be in the same range and usable.

Both my lenses have shot over target by +0.75, which is not a great result, but luckily still very useable for me, because my premium lenses covers a big range.

So I will not risk Lasik, even that it was a part of the package, if I wanted it.

If I had gone for monofocals, which I could easily have chosen, I would not have had any close up vision with this result, so in my case it is kind of backwards, I was "lucky" I went for premium lenses, so I am still free of glasses most of the time.

Refractive surprises is always a risk, and I think it is important to be mentally prepared that it can happen, even that most get good results, I believe I saw s statistic showing that 4 out 5 hit target within -/+ 0.25.

Although all this is worrisome - I remind myself that there has been a lot of advances since my grandmother's surgery. Cataracts was a leading cause in blindness in seniors and for whatever reason seems to hit middle age people now too. I am thankful I can see and have useful vision - carry on with my job etc. If the worst if this is still dealing with glasses (well I have had that since my childhood illness - high fever with red measles - my vaccination didn't work).

The stats indicate a very high success rate and we can research and learn about our options and choose best lens for ourselves but at the end of the day the surgeons do a good job and our lived are better than when we lived with cataracts.

I also have some adversion to Lasik corrections for fix errors. I may opt for simple prescription eyeglass correction if the error is significant. I see that AcrySof makes claims that they have improved the stability of their lens over time. But, of course everything works perfectly in sales materials!

Yes, we should not complain I guess. Times have certainly advanced from when the natural lens was simply removed.

Hi Sue and Viking 😉

for whatever reason seems to hit middle age people now too.

You think the rate has increased in last 100 years? I feel not. Maybe because of internet we read more?

.

Anyway just few hundred years ago most would have been dead by 50 😃 Our eye/body is just not designed to last that long 😦

.

For the unlucky people on this forum, the eye wants to stop working even quicker than the new normal!!!

Ron don't overthink. You did your research and you are on a good way. You will be ok hopefully. Do you have anyone who can put drops for you after the OP?

.

Any marketing material from any manufacturer is almost as good as junk 😃 Not always but you know what I mean.

.

So which manufacturer/lens are you going for?

Both my lenses have shot over target by +0.75

Did it move more? I thought it was around +0.5?

Hi 😃

The lenses moved around a lot during healing I think.

But yes, at some point it was even plano on the trifocal eye, but at an extra check about 4 month after surgeries (I think they were curious about the mix thing) the measurement showed +0.75 both eyes, and astigmatism 0.25 both eyes.

Both are toric 3.0 lenses, so they did a really good job about the astigmatism, but the power thing was a joker.

I had very dense cataracts, and my numbers are really high (29.5 both eyes) so the odds were not that good for hitting the target, I knew that.

My far vision is exactly the same if the vision is corrected to plano, so the "only" downside is that I have lost some near vision I could have had, if targets had been hit.

But reality is that I rarely use glasses, I work many hours each day in front of the pc without glasses, I work on motorcycles and stuff mostly without glasses, i can read normal text on paper without glasses, I only use glasses for extensive reading or small stuff, so I think my result is the old story about choosing to enjoy what you have, instead of thinking what you could have had 😃

Reality is I can do so many things now I have never been able to do my hole life, so beside running my company I am now taking an education to become a hypnotherapist - just because I can 😃

Before surgery I could not read a book or see something presented on a whiteboard, so I think it is fantastic to be able to do these things now.

Anyway, I am very happy your wife have ended up with such a good result, I think you both deserve it - I hope your own eye condition is healing as well.

Cheers

I am not looking forward to the drops thing. So far I have been really happy that I have not been flagged as having dry eyes, and being pressured to go down that road. I have been told that I will get two types of drops in a kit. I am to take Vigamox three times a day for 1 week, and Durezol once a day for three weeks. It is claimed this is 50% fewer drops than other generic options... My wife does does drops for the dry eye thing, so yes I guess I have help. I suspect I will dislike it but manage... I have a friend that went for the PanOptix lenses in both eyes. I couldn't believe the number, cost, and duration of the eye drop rigmarole she went through before and after each eye. $5,200 and now she wishes she had never had them put in.

As far as lenses I am still thinking about it. But unless I change my mind it will be:

1. First Eye - Alcon AcrySof IQ Aspherical Monofocal IOL
2. Second Eye - Still somewhat up in the air. It may be the same as the first eye, or it may be the toric version of the same lens. Apparently my astigmatism in my second eye is "irregular" and may or may not be suitable for a toric lens.

As far as overthinking it, that is almost guaranteed with our Canadian health care system. They give us enough waiting time to overthink things big time!!!

Ron, drops are only a minor inconvenience, and easily self administered. You just have to remember to use them at the scheduled time and make sure you hands are clean. They do not irritate or burn. I used the prescriptions drop for 4 weeks, along with my previous prescription drops to prevent glaucoma.

I also now use Systane Complete, non prescription, four or five days to keep my eyes hydrated. Another minor annual expense. It just like remembering to drink lots of water.

I do think that the number of younger cataract patients has risen (based on what surgeons are saying). Perhaps they are including patients opting for clear lens exchange? But in my case the early cataracts were due to steriod use. I have used the creams and been on prednisone for autoimmune diseases. Use of steriods has been on the rise so I am sure that would have an impact on number of cataract patients too.

My personal opinion is that the sun has also had an impact. I am going through skin cancer treatment (2nd time). My dermatologist says she she's this in 20 year olds now and the % is growing. If the sun has that much impact on skin what does it do to our natural lenses?

as a fellow Canadian I can relate! It is wait times that get me going! But on upside I had minimal expense for cataract surgery - just upcharge on Symfony lenses ($900 per eye). Work health plan covered the drops.

One thing you may want to add is either flaxseed oil capsule or Omega 3. I find it helps with dry eye. The cataract surgery itself often causes the dry eye. Gets better with time but I still see other benefits to adding the flaxseed oil as a supplement.

Sounds like you have a solid plan - wish you a successful outcome.

I already take Omega 3 daily and have done so for years, despite all the conflicting reports on whether it is good or not. I am not a big fan of fish, so taking Omega 3 is my substitute for eating salmon and the like...

Part of my wait time is my own fault. I have been diabetic for 20 years or so and was having annual eye exams to determine if any retina issues associated with diabetes were developing. I was initially seeing a retina specialist, but he basically chased me away and told me to see a good optometrist annually, as he was not seeing any issues. That was fine, except I overlooked going for an exam for 10 months or so. I only went in when I noticed I had blurry and double vision in one eye. If I had gone in for an exam when I should have, I would have probably gotten into the cataract surgery queue 10 months or so earlier. It will be interesting to see how long I wait for the second eye. I currently have 20/20 vision in it, but a cataract is developing. Will have to see when they agree to put me on the wait list. It is hard to argue that it is a pressing health issue when I have 20/20 vision. I'm sure there are many others out there with much worse vision (probably still driving) that need the surgery time slot ahead of me.

i live in NB and was told they only do the cataract surgery when eyesight was 20/40 or worse (covered by medicare). i was at 20/60 and 20/40 - best corrected with glasses so no choice for me at 53. I still gad a 3 month wait to see surgeon and and initially another 3 month wait for surgery. I had more questions so made another appointment to see surgeon which delayed my surgery another 2 months.

However i would advise waiting till you feel as confident as you can be with surgeon and your choice of lenses. Wish you well.