Dealing with Refractive Surprises
Posted , 6 users are following.
I think that most, but not all patients go into cataract surgery knowing that the results are not as exact as getting a new eyeglass prescription. I think we hope for the best with our IOL surgery, but sometimes there is still a surprise in what we actually get. Statistics are not all that encouraging in that only about 75% of the time is the resulting outcome within +/- 0.5 D of the target. Not getting what we expected especially if the surgery has cost us thousands out of pocket per eye, is a big disappointment. So what can be done about it? Here is an article that gives the opinions of some surgeons. The response varies quite a bit. Some say they think they have to fix the first eye by changing the lens power before they go on to the second eye. Others will learn from the first eye and try to compensate the miss on the first eye with a better outcome on the second eye. Others will recommend laser surgery or a piggyback lens. And, I suspect many or perhaps even a majority just dismiss the miss as normal, and suggest you get glasses to correct it.
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To me the most important thing is that unless absolutely necessary, do not get the second eye done until after the 6 week post surgery eye exam is done. Then you and the surgeon will know what the outcome of the first surgery is. This will provide at minimum an opportunity to do better on the second eye. The other potential action one can take is to leave the eye that you want the most accurate result in to be the second eye to be done.
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In any case here is the article:
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Review of Ophthalmology Sean McKinney, Senior Editor PUBLISHED 10 SEPTEMBER 2021 Responding to Refractive Surprises
3 likes, 26 replies
Lynda111 RonAKA
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Well said, Ron
I do think many cataract surgeons think that eyeglasses can always correct refractive surprises.
Medicare will cover in. full a standard monofocal in the USA, and most patients choose that. Now when patients pay upfront $4000 or so for a multifocal and it doesn't please the patient that's. when they have to scramble to do something to 'fix' the problem. Also I think most surgeons do both eyes within 3 weeks as mine did.
RonAKA Lynda111
Posted
Yes, unfortunately many surgeons just want to get it over with and have no plans to learn something from the first eye, and apply it to the second eye. And, that is about the very minimum they should be doing.
soks RonAKA
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i cant believe the surgeon indifference to actually resolving someone's issues.
mike38903 RonAKA
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Are surprises mostly on the positive side or the negative side? I guess they just happen randomly in either direction. My original target on my first eye is -1.25 D, and my surgeon's calculation results show that the closest options for me are -1.08 D and -1.43 D, and she suggested I pick -1.43 for better intermediate vision. Hope I won't end up with something below -2.00 D, or would I be better off choosing -1.08 D?
I have mild dry eyes. Not sure if this would have an impact on my eye measurements and thus on my final refractive outcomes.
Lynda111 mike38903
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Dry eyes can affect eye measurements for your IOL. When I was told I had dry eyes I went on a dry eye drops regimen for 2 or 3 weeks before they took measurements. And about an hour before measurements were taken, I instilled them in my eyes.
RonAKA mike38903
Posted
I think they can be on either side of what is predicted. Once you have the first eye done however, the miss on the second eye is likely to be in the same direction and of a similar magnitude if the eyes are similar in dimensions. The surgeon I had says he always learns something with the first eye that he can used with the second eye.
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If this is the close eye for monovision I think I would go for the -1.43 D target. -1.08 may leave you a little short of good reading vision if the lens being used is a monfocal. I have -1.40 in my near eye and I am quite happy with it. Works well and I very seldom need reading glasses.
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If your surgeon will give you the IOL measurements data sheet (from the IOLMaster or Lenstar) you could do the calculation with other formulas. Each formula will predict a little different number, and the range of them may give you more confidence in one pick or the other.
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The formulas you can find on line to use include:
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Based on what I have seen I would trust them in that order. The first two have been shown to be most accurate when you are targeting myopia for monovision.
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Yes, as @Lynda111 points out dry eyes can have an impact. Some surgeons recommend drops before eye measurement. The surgeon I had did not recommend them and used the Hill RBF formula, with accurate results. I have had varying opinions on whether I had dry eye or not.
mike38903 RonAKA
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Hi RonAKA,
I just got my calculation sheet, and my surgeon used Barrett Universal II for calculation. Now I am trying to do it in Hill-RBF Version 3.0. I entered all the required info, but the Calculation button is still greyed out. I used the A-constant from the manfacturer's website. Did I miss something? Any idea as to how to make the calculator work? Thank you!
karbonbee mike38903
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Regarding having dry eyes, definitely start using preservative free lubricating drops as soon as possible, it will make a difference in your surgery results. The clinic I went to told me to start the drops a month before I went for the pre-op scans to make sure my eyes were as healthy and balanced as could be before doing the scans. Continue them post surgery also, just wait thirty to sixty minutes pre or post using the prescription drops so those drops get absorbed properly before using the lubricating drops.
RonAKA mike38903
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I have had trouble with the Hill calculator when using Chrome. I got it to run with Microsoft Edge though. It is very picky about the data. You have to be sure you put the date in the right format, and the gender. If you mouse over each field it should highlight the offending one in red. You also have to be sure to select the instrument used for the measurements.
mike38903 RonAKA
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It seems that Hill calculator is not Chrome friendly. as some required fields are displayed in a way that can be easily missed. I only saw those fields when opening the calculator in Firefox. Perhaps I should blame my cataracts for the miss!
I tried both Hill and Kane, and got the same results as those produced by Barrett Universal II when A constant was set at 119.10 as suggested by the manufacturer. HIll suggests using 119.20 for A constant and the results look closer to my target refraction. With Kane, its embedded A constant is 119.31 which pushes the result even closer to my target. So, A constant makes a big difference and those calculators all prefer to use their own A constants for the same IOL.
Lynda111 karbonbee
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Well said. I wish more cataract surgeons advised patients to use eye drops. I like Systane Hydration preservative free in multi dose bottle. From Alcon.
RonAKA mike38903
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When I have used them. I used the A-Constant recommended by the manufacturer of the lens. One thing you have to watch for is to use the A-Constant for the type of instrument used to measure the eye. The IOLMaster 700 and Lenstar 900 for example are optical instruments, so you need to use the optical A-Constant. Other instruments that can be used are ultrasonic and use a different ultrasonic A-Constant. And the wild card is that some surgeons use their own modified A-Constants based on their personal experience with the lens.
karbonbee Lynda111
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Thank you. I was surprised they told me to do it, but really happy that they did. My eyes have always been somewhat dry, but I didn't realize that there were preservative free ones that don't cause long term problems. I've found them to really help. I haven't tried Systane, although I've read good stuff about it. I tried Refresh, Hydrasense, Oasis and Thera Tears. I read lots of people raving about Oasis as it's prime ingredient is glycerin, and went to a lot of trouble and cost to find it, and was really disappointed with the results -- it's underwhelming at best, lol. Thera Tears is really good, but I just found out that it wasn't totally preservative free, although apparently the small amount it does use dissipates quickly after application and most people weren't bothered by it even after long term use. I find Hydrasense is okay, but Refresh does the best long term job for me. I just really hate those little individual application tubes -- such a waste -- wish they still had the preservative free drops available in the little multi dose bottles. If Refresh hadn't worked as well as it does, Systane was going to be my next choice.
Lynda111 karbonbee
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I hate the individual bottles as well. that's why I use Systane Hydration Preservative free in a multi-dose bottle. Systane Balanced is also good.
Lynda111 karbonbee
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No, Karbonee. I have the actual carton/bottle in my hand. It says "preservative free."
If it wasn't I would not take it. I buy mine at Walmart,
Lynda111 karbonbee
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You can also just Google "Systane Hydration Pf " and see for yourself online both at Walmart and at Alcon website
karbonbee Lynda111
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Ahhhh, the one I was looking at didn't have the "pf" at the end. The one you have isn't offered on Amazon in Canada, and it says it's out of stock on the US version. Thanks for the clarification. Checked Walmart in Canada, and they don't have that version either, and the Alcon website only offers it for sale in the USA. Oh, well. It also contains hyaluronate.
RonAKA karbonbee
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I recall that Costco carries Systane. If I can remember I will check it out when I go this week to see what one it is.
RonAKA karbonbee
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I checked at Costco today. They have Systane Ultra which is preservative free at $23 regular price for 3x10 ml vials. They were on sale for $18 today.
karbonbee RonAKA
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Oh, thank you for checking. I want to keep away from the vials though, that's my problem with Refresh -- their drops work great for me, but they're only available in the little vials. I ordered Thealoz Duo which comes in a bottle, is also similar to Hylo and is also phosphate free. In general, I think it's probably good to use a couple of different brands, that way your eyes are less likely to develop a reaction to them, even if they are preservative free. Have you tried Systane yourself?
RonAKA karbonbee
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I probably used the wrong wording. The Systane is in 10 ml bottles like the HydraSense. My wife has used it, but did not give it the seal of approval and still likes the HyLo.
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The HydraSense night version so far has not been the silver bullet for my issues. I am thinking more and more that I am opening my left eye in the night. I bought some more of the HyraSense Advanced at Costco and will continue to use them in the morning and at night when the Night Gel version runs out.
karbonbee RonAKA
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Ahhhh, okay. Thanks again. I will check the next time I'm in there then. That's too bad about the HydraSense not helping. I think I had told you before, that I thought it was okay, but found a much better response with the Refresh, despite the little vials I don't like. If you can, maybe try the Refresh Celluvisc gel drops for overnight? I noticed a big difference between it and the HydraSense when I used them on different eyes at the same time -- and the Refresh was being used on my problem eye. I found that even the regular daytime Refresh Plus did a better job than the HydraSense Overnight Gel ones did. Although, I just checked it, and although I paid twenty bucks on Amazon for thirty vials, of the Celluvisc, now it's up to forty... yikes. You can use the little vials for more than one treatment, the little top can be put back on, but still...
Lynda111 karbonbee
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Refresh Relieva PF also comes in a multi-dose bottle
karbonbee RonAKA
Posted
What I also found really helpful with regards to the dryness in my left eye in particular, was using a moist hot gel eye mask. It stimulates your own tear ducts and their production of natural tears, while soothing your eyes. I started using one a couple of weeks prior to my surgery and it worked wonders, especially in conjunction with the lubricating eye drops. I haven't used it since the surgery as they are somewhat of a weight on your eyes, and I didn't want to take a chance of it shifting something by accident. I can't wait until I can start using it again though, as my eyes loved it. Both Bruder and Oasis have one that has a really good reputation. I wanted to get something a bit cheaper to try out with, and got one off Amazon for under twenty dollars that has been working quite well (thermobeads by proactive). You have to be careful when heating them up as if you go too high too quickly, you can cause the gel beads to explode in the microwave, so you have to experiment with your own microwave. I do mine in increments so it will retain enough heat for the ten minutes I use it for without being too hot to use. The one I got can be put in the freezer for a cool eye compress also -- it's good for tired eyes.
RonAKA karbonbee
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While I think I said that the HydraSense was not the silver bullet, it does seem to help. It is looking like I need to use the drops 2 to 3 times a day. I forgot them this morning and needed to put them in early in the afternoon. My biggest issue these days is the PVD in my most recently operated on near eye. The PVD in my distance eye was distracting while driving, but the PVD in the near eye is distracting while using a computer. It is almost always visible and near the middle of the screen. I am seeing my optometrist this coming week, but I know there is nothing they can do about it short of an vitrectomy, and it is not bad enough to warrant that. I am just going to have to wait for the visibility of it to decrease as it has in my other eye.