 and he will be talking about residual refractive air after cataract surgery. And he comes to us by way of New York College of Medicine. And I'm not going to give you the full name or the full titles and all these. I will let them do that because they are a little long. So I was giving them a hard time about that. They are a little long. Morning, everyone. I'm John. Nice to meet you. Friendly reminder, please register to vote. Election days November 3rd. So today I'm going to talk briefly about residual refractive air after cataract surgery and a new lens that our lab has been studying. Briefly, there are about three million cataract surgeries that are done each year in the U.S. And it's been estimated that over 20% of the eyes after cataract surgery are more than one diapters of plant refraction and there's 1% that could be more than two diapters of plant refraction. This is a study of expanded IOLs. Each year we receive about 20 to 40% of expanded IOLs that were removed secondary to incorrect IOL power. The good news is that however, in a paper published in 07 by Dr. Crandall that it seems to be downtrending. In this study, a prospect study of over 17,000 eyes in Sweden, about a third of their patients ended up slightly a hyperopic or a myopic when only 11% of that was planned and only 50% or so were hematropic when over 78% were planned. Another area where refractive error is a major issue is in pediatric cataract surgery. Aside from PSO, it's one of the major factors affecting outcomes. In younger children, there's a very large and unpredictable myopic shift. If you look here, small numbers, but in this group of less than two-year-olds who were studied for three years after the first cataract surgery, their refraction was over three diapters of hyperopia and they ended up around half diapter of myopia. Additionally, IOL power calculations are much more difficult in less than two-year-olds. So what options are available? In the photorefractive realm, we have LASIK, PRK, LRIs, and LASIK and PRK have been shown to be more effective and more safe in smaller refractive errors. And in the intraocular realm, we have IOL exchange and piggyback lenses, which my lab mate, Nick, will talk more about, and even light-adjustable IOLs. However, all of these have side effects and even the light-adjustable IOL, which several studies have shown to be pretty useful are quite expensive. The light delivery system is, by itself, over 100,000 euros. So which is best? As I said before, so small spherical errors or even the stigmatism LASIK and PRK, but when you have large spherical errors, piggyback IOLs have been proven to be safer and more effective. However, these patients tend to not do as well as younger patients who get LASIK or PRK, and their final vision might be 2030 or 2040. So this is our test lens. It's the Clarivista Hermione Modular IOL system. There is a base component that has a diameter of about 8.5 millimeters, and there's a separate optic component that's 5.8 millimeters. And the optic component itself can be either toric, multi-vocal, mono-vocal, et cetera. And the base component itself has a lip inside where the optic can be tucked in so that it stays in place. Additionally, the design has square edges both in the base and the haptics for decreasing PCO formation. We've also done previous studies studying the PCO formation and the stability of the lens in a six-week study with rabbits. We found that central PCO at the end during gross examination was much less than in the control lens, so 3 versus 0.58, and 4 is the maximum number for PCO. Additionally, we found the lens to be very stable and there was no anterior chamber toxicity. We think that the PCO formation reduced because, if you look back here, the lens itself has a nice square edge that's further out than the acrosol, which is only 6 millimeters versus 8.5 millimeters, and the haptics itself are also a square edge. So in our current study, we studied the stability and ease of IOL exchange using this modular system. We used five New Zealand rabbits in the right eye, we had the study lens, in the left eye we had the acrosol control. We followed them weekly until week 6, and we did an IOL exchange procedure at week 2 to allow for post-op inflammation to decrease and to allow for any cortical proliferation to start, and we did a final one at week 6 to allow for access to lots of PCO formation and cortical proliferation. Finally, we euthanized and nucleated and did some gross and histopathologic examination of these rabbit eyes. So here is a video of the implantation procedure done by Dr. Manlis. It's sped up five times. Here, let's see, the base is being injected. There's a nice blue color to help visualize the base itself. We need to use regular tools. Here's the injection of the optic itself. So it's pretty easy to inject, pretty easy to tuck in. Here is a week 2 slim exam. The results are similar to our previous study where there's a slight reduction of PCO, not statistically significant. And here are some videos from our week 2 IOL exchange. This is the study. You can see the optic is pretty easily popped out. Let's use this as favorite McCool scissors. The optic is injected. That's real talk, by the way. This is, sorry, this is 10 times speed. All right. And here we have the study control acrosoft lens. There is more manipulation of the capsular bag. Manipulation required to remove the loops from the equatorial region. Here we have injection of the new acrosoft lens. So it's pretty easy to detach the optic from the base. However, there was some pupil myosis, as you can see here, after some manipulation. And it was a bit more difficult to visualize the optic after injection. The control lens wasn't significantly more stuck, but more manipulation was required, removing the loops from the equator and having to manipulate the capsular bag. So in our week 4 salient exam, sorry, it's cut out here, but the optic of two lenses were not completely under the lips. You can see here and here, which probably came from the difficulty in visualizing the base and the optic after pupil myosis. And you can start seeing some crazy synechia, but because there was manipulation, these results are a bit confounded. And here is week 6. There is also a trend for decreased PCL formation and you see lots of synechia and even anterior cortical proliferation. And this was what we wanted to assess in our week 6 explanation procedure. Here are some videos from our week 6 explanation. Again, the optics pretty easily popped out. The base can be nicely visualized. It's very stable inside the capsular bag. Acrosol. Significant synechialis is required. This is also 10 times speed. So in general, again, it was pretty easy to disengage the optic and the base itself remained very stable in the capsular bag. In the acrosol, there was lots of synechia and much more manipulation removed from the equator. There was a lot of proliferative material, probably caused from this staring up of the proliferative material during the second explanation procedure. And there was a significant amount of zonular stress. In our gross examination, we noted that the base itself was very, very stable in all four eyes. This is the control of the... These eyes are apicic. While we didn't really study PCO in this... In this study, we did notice a bit the decrease in summering ring and PCO. And here's a good picture of why we did not assess PCO in this study because if you can see here, the surgery itself even pushed the proliferative cortical material into the interior of the iris. Here you can see there's nice... The capsular bag's pretty nice in the study lens. So, what conclusions do we have? The implantation exchange of this optic in the test lens was much easier than control. Standard instruments were used and there was much less zonular stress. The base component itself remained very stable and centered. And in our previous study, we showed that there was much less PCO formation in the test lens. Human trials are ongoing. And so this could be applied in pediatric surgery, et cetera. Our references. And thank you to Dr. Werner and Dr. Manlis. It remains stable. I don't know if we assessed... We couldn't. Thank you.