 So our next presenter for Grand Rounds is going to be Caleb Morris. He's a third year medical student who's visited from Duke for the past 10 months or so and spent some time in the Manless Wernhert Laboratory. He's done a great job and he's dreading going back to real medical school here in the next couple weeks. Dr. Wernhert is going to introduce him a little bit with the introduces talk a little bit before you hear from him. Thank you very much. Good morning. So this is just a brief introduction to Caleb and Caleb's subject. So here you have the structure of our lab actually and here you have our current fellows and they are finishing this week and here are new fellows. They already started last week and we put here Caleb as honorary fellow because he actually spent a total of 10 months with us and this is also his last week. So how does this go from three women as well to three males? That's going to be a very interesting transition. Yeah, we couldn't do three women again. We definitely need a break I think. No, we had a great year and I'm sure you're going to have another great year. So in any way, so Caleb comes from Duke University and for him to be here, Duke University required him to have a major project so he was involved in everything we did in the lab but he had a larger involvement in this particular project here. So as an introduction you are probably all familiar with the term of glistenings which are these fluid field micro vacuums that we are going to observe inside the optic of intraocular lenses when they are in an aqueous environment. They measure at around 10 microns in general and they are throughout the optic substance. They were originally described with hydrophobic acrylic lenses especially with the aqueous off material but they can actually be observed with different lenses. However, you may not be very familiar with the concept of nanoglycenings and there are a few papers in the Japanese literature calling this whitening of the intraocular lens and there are a few papers describing this just as surface light scattering. So this was also originally described with the three-piece Acrysof lens and I just want to show you what it is. So you have here two intraocular lenses, there are three-piece Acrysof. You have the explant on the left side, this is actually a lens that was removed from a cadaver eye and it was inside of the cadaver eye for around five years before the death of the donor. And on the right is the control, it's a brand new lens removed from the packaging. So both lenses are in the water bath and for this particular photograph, the light is coming from above. So now I'm going to show you exactly the same lenses, exactly in the same position, nothing was changed, the only thing here that was changed was the lightning. So the light is not coming from above, the light is coming from the sides, from the left and from the right side. The lenses are in the exact same position inside the exact same water bath. So you see that there is no change in the control, but these explanted lens actually acquire this whitish discoloration. So that's what it is. And the way you see that in vitro is exactly the way you are going to see under a slit lamp examination. So according to the position you put the light in the slit lamp, you are going to see this acresoft lens getting this whitish discoloration. And once in a while you get some emails of surgeons saying, I believe the acresoft lens that's inside of the eye of my patient is calcifying. So it's not calcified, there is no calcification with hydrophobic acrylic lenses, which this is. So I like this schematic drawing just to show what actually this is. So you have the optic of the lens here and the glistenings are inside of the optic substance. And you can actually measure these vacuums that are on 10 to 20 microns. They are filled with fluid, but the whitening or the nanoglistenings, they are strictly on the surface of the lens, anterior or posterior surface. And basically these are small water aggregates that you visualize. And they are very, very small, you cannot really measure them, but they give this appearance of whitish discoloration according to the incidence of the light. And in our laboratory we have a shine-flug device with the instantometry analysis. So that's exactly how this lens here is going to look. The outline of the optic is very, very bright and you can actually measure these incisities. That's a measure of brightness. So here the values are very high, more than 100. And the control lens is going to look like that. So a very dark outline. So this is just a brief introduction. We are doing a series of studies in our laboratory on this subject. And Caleb then is going to present about some of them. I'd like to thank Dr. Werner for that introduction. At this point you know more than I did about nanoglistenings a year ago. Hopefully I'll prepare you to listen to this talk. As Dr. Werner mentioned, the initial studies done on these lenses and uptell about when we started this study, these lenses had mostly been studied in a three-piece Acrosophio, a very specific lens and not in other lenses. So the first thing we wanted to know was, is this a phenomenon that's unique only to the three-piece Acrosoph lens? The lenses that are used now more commonly are the single-piece Acrosoph lens. And changes in both design going from a three-piece to a one-piece and also material incorporation of a blue light filter in some of those lenses may have changed this presentation. And so what we wanted to know and our question was, are these same nanoglistenings seen in the other Acrosoph lenses? So the purpose of this first study was to investigate the potential effect of surface light scattering on light transmittance of the single-piece hydrophobic acrylic intraocular lenses with or without blue light filter. For our study, we obtained 49 hydrophobic acrylic IOLs that were removed from donated human cadaver eyes. 36 of these had the blue light filter and 13 did not. For controls, we had controls that were supplied by Alcon and they were nice enough to match these to both the power and model of the expanded cadaver lenses. We measured the surface light scattering, as Dr. Werner mentioned, on our ShineFluid camera and light transmittance was measured on Perkin-Elmer spectrophotometer. And it's important to note that we used a single beam configuration with an integrating sphere set up and we'll talk more about that later. This is a picture of the ShineFluid camera. On the left here we have the specially designed eye model. It mirrors both the curvature and dimensions of the human eye. And we place the IOL inside this holder and then fill it with either BSS or distilled water. It's then placed here on a special holder that was designed for on the ShineFluid camera. For the light transmittance measurements, these were made on the spectrophotometer here. And again, we had to have a specially designed holder that fit into the cuvette. In both cases, the anterior surface of the IOL was measured towards the light source, and it's placed here in the little box. The measurements, as Dr. Werner mentioned, are reported from the ShineFluid camera in CCTs or computer compatible tape units. And these measure brightness of the light that's reflected back at the camera. And it's measured from zero, which is black or no light scattering up to 255, which is white, or high levels of light scattering. Here's a picture of a gross image of what we see with the lenses of the blue light filter. The top image is an image of the lenses in the dry state. On the left, you have the control lens, and you can see it's very clear. On the right, there is the x-planted lens. And sorry, some of this is cut off a little bit, but I'll tell you what those things say. So on the right, you can see that there's a little, there's few focal areas of reflection. And these are consistent with yag pits in the lens. In the second image, the lower image, you can see these are hydrated lenses. Again, the control is very clear. On the right, the x-planted lens still has those yag pits in it. And then there's also some areas you can see a little bit of evacuated focality throughout the lens, and those are consistent with glistening. The most apparent thing, though, is the surface light scattering, and that's this milky yellowish color throughout. And there's no focality at all to it. It's very diffuse. Shinefully, the image is of these same two lenses, so you can get an idea of what this looks like. The top image is the hydrated control, and it has very low levels of surface light scattering, about 10 for both the anterior and posterior surface. The lower image is the x-plant, very high levels of light scattering. You can also see in the middle, there's a little bit of light scattering from some glistening, but the most light scattering is the anterior and posterior surfaces, and that's as high as 226, which is quite high on the anterior surface. Again, this is same views, but of the lenses without blue light filter. The top image is dry again, and both of these are very, very clear with the control on the x-plant. In the hydrated state, you can see that the x-planted IOL has some focal areas of reflection consistent with glistening, and then the diffuse light scattering throughout to make you whiteness. Again, here, very low levels of surface light scattering on the control lens, and much higher on the x-planted IOL. In this case, as high as 151 on the anterior surface. Here's a summary of the data that we got for the surface light scattering. For all the lenses with blue light filter, the mean of surface light scattering for both the anterior and posterior surface was 38.4, plus or minus 46.1 CCT. So there's a lot of variation. The range is quite large from 4.8 to 202.5 CCTs, and that's for the mean value. The control for both were quite low. For the lenses with the blue light filter, it was 5.4, plus or minus 2.3 CCTs, and the lenses without blue light filter, the x-planted lenses were 64.6, plus or minus 43.6 CCTs, and again, very low in the control. Part of the reason I want to call your attention to the large range and the variance in the light scattering on these lenses is that these lenses were x-planted, and we tried very hard to get lenses that had known dates of implantation so we could know how long they were in the eye. Here you see a plot showing on the y-axis the CCTs or the light scattering that's occurring and the years of implantation of that lens. You can see that there's a tendency for the light scattering to increase over time. This is something that was seen in the 3-piece lenses as well. Here's a graph of the same two lenses with blue light filter, the control and the x-plant, and their pattern of light transmittance. You can see that they mirror each other very, very well, and in this case, the transmission begins to decrease around 500 nanometers, and this is consistent with the blue light filter. The light transmission that we measured, and also the latest papers that have come out on this subject, set the visual spectrum as 400 to 700 nanometers, so that's what we used for this paper as well. The control had an average light transmittance through this spectrum of 83.19%, and the x-plant was 83.20%, so you see they mirrored each other very closely. This is a slide of the same lenses without the blue light filter that you saw previously. In this case, this is the typical pattern of light transmission. I'm going down to right around 400 nanometers, where the UV blocker takes effect. In this case, the mean light transmission was 96.88% for the control, and 96.06% for the x-plant, so again, very, very closely matched. Overall, for all the lenses that we measured, the mean light transmission for the lenses with the blue light filter was 83.69%, and the control was 83.76%, so very close. The paired t-test, the p-value was 0.4%, so quite high. Again, the lenses without the blue light filter, similar picture. 95.91% was the mean for the x-plants, and 96.02% for the control. Again, a high p-value of 0.487%. So you see that they were very similar in light transmission. So for this first study, the conclusions that we had were that surface light scattering was indeed higher in the x-planted IOLs, quite a bit higher. Surface light scattering appeared to increase with time. The Acrosoft material in a single piece design, with or without the blue light filter, is also susceptible to high levels of surface light scattering due to nano-glistening. Increases in the surface light scattering did not, however, have a significant effect on light transmission in the visible spectrum in the single piece hydrophobic acrylic lenses, with or without the blue light filter. But at the end of this study, we had, we confirmed that this phenomenon was still occurring in the Acrosoft lenses, but we didn't, we still wanted to know whether or not this was occurring in other lenses. Was this specific just to the Acrosoft material or in other materials, including other designs of hydrophobic acrylic lenses? So the follow-up study that we did, we evaluated surface light scattering and light transmittance in previously unstudied IOL material and design types. And this was our question, is surface light scattering specific to the Acrosoft material? So we had four different material types that we collected, hydrophobic acrylic, hydrophilic acrylic, PMMA, and silicone lenses. We had four types of the hydrophobic acrylic lens. The three that have been previously studied wanted to enlarge that data set and confirm our previous results. And then we also wanted to see in a different material type, the SENSAR material from AMO, if it had similar results. We had two types of hydrophilic acrylic lenses, two types of PMMA lenses, and three from the silicone material. We obtained one control for each IOL type with the exception of the PMMA and hydrophilic acrylic lens. All of these were matched to the model and manufacturer. For the PMMA and hydrophilic lenses, the model and manufacturer were unknown. So we selected lenses from the silicone material. And in this case, we did not select lenses, control lenses for each lens based on the power of the lens because Acone et al. had shown that the diopteric power did not cause variation in light transmission measurements if the single beam configuration and the integrating sphere setup were used. That's what we've been using all along in our spectrophotometer. And we've seen that in our own studies as well. So we went ahead and our primary outcome measures were, again, surface light scattering and light transmission, and these were measured in the same way as in the previous study. We found again that the surface light scattering was comparatively higher in the hydrophobic acrylic Acrosoph IOLs and particularly in a three-piece design. And this is interesting because the three-piece design is the design that was introduced first and characteristically has had the longest duration of implantation in our studies. And we pulled all of the data for the Acrosoph lenses and we had 18 lenses overall from the Acrosoph material type. One of them, we did not know the dates of implantation so we did not include it in this dataset. And here we've plotted the surface light scattering over time of implantation. And you can see that there's a strong correlation or tendency for this to increase with time. The correlation coefficient for this was 0.7, so quite high. Here we have some representative images of the results we got for the surface light scattering. These four images are of the hydrophobic acrylic type. The first three are all the Acrosoph material top tier, the one-piece design with and without blue light filter. You can see they have moderate levels of surface light scattering in the 50s and 60s for the anterior and posterior surfaces. The third lens here, lens C, is a hydrophobic acrylic Acrosoph lens with a three-piece design, characteristically longer duration of implantation and has quite high levels of surface light scattering, the 197 to 182. And these three lenses, you can also see these little bright dots inside the lens if you look closely, are consistent with glistening. The fourth picture was a surprise to us, it was unexpected. This is the SenseR lens. It has been studied in one small study clinically before where shine-plugged images were taken and no significant backscatter was seen in any part of the lens. So this is interesting because we do indeed find low levels of surface light scattering but there's this bright, diffuse reflectivity throughout the middle of the lens and had not been seen before. It's also different than other things that you see that can lead to light scattering in the middle, but those would all have focal brightness instead of this diffuse lightness throughout. So our initial thoughts on this are that the previous study that did not show any of this internal scattering was done clinically in non-explanated IOLs and so they weren't subjected to the preservation processes that occur with explantation. One of these is the introduction into formalin and we'd like to do some further work up to find to see if we can figure that out because at least for the Acrosoft lens studies have been done to show that the preservation process and the processing that we use in this study have not affected the material and led to any changes in light scattering. So at this point we think it may be related to formalin fixation, but we're not sure and we'd like to look into it more. These next four images are of the other material types. The first is from the hydrophilic acrylic group and then we have a PMMA lens and two lenses, the silicone plate and silicone three-piece lens. And these lenses all behave pretty similarly. There's low levels of surface light scattering throughout the PMMA lens that you see in the upper right-hand corner had the lowest level of surface light scattering and interestingly also had the longest duration of implantation. So at least in these lens types it does not appear to be related. We have our results for the light transmission measurements. This graph just shows you characteristic light transmission curves for each of the lens types. You can see that most of the variation occurs between 400 and 500 nanometers. Again this first red line is the hydrophobic acrylic one-piece with blue light filter and you can see that that has on-site of action around 500 nanometers. The rest of them all group pretty tightly around 400 nanometers and you can see most of the variation is due to the on-site of action of the UV blocker. Overall our results for this showed very very tight grouping between the X-planted lenses and the control lens for each group. The one small exception to this was the PMMA and the hydrophilic acrylic groups and these are the groups you can remember that we did not know the manufacture for each of the X-planted lenses and so we thought that a lot of this variation was probably due to differences in the UV blocker and this next slide you can see we graphed out all of the PMMA lenses and you can see that the variation again very tightly grouped up until around 400 nanometers where it appears that the UV blocker was different from manufacturer to manufacturer and induced this variation because some of that is included in the wavelengths that we measured from 400 to 700 nanometers or a visual spectrum. Another interesting finding that we had was in the silicone plate IOLs and you can see that this one light transmission curve was very different than the others and it appears that this one lens was manufactured before the incorporation of the UV blocker so quite early and does not have that steep down slope below 400 nanometers. This didn't affect our results significantly because the calculations that we did were taking into account the visual spectrum for 400 to 7 nanometers where the other lenses also had full transmission. So in conclusion, this is the first study that's been done to evaluate light scattering and light transmittance in IOLs manufactured from different materials. One of the interesting findings that we had is that we consistently did not see a decrease in light transmission correlating to light scattering although previous and very early studies on light scattering done by Matsushima and Yoshida at all had shown a significant decrease in the few lenses that they did in lenses that had surface light scattering and those lenses, at least for the three from Matsushima, they were dislocated not for visual complaints but for dislocation and so the patients seemed to be seeing fine until the lens dislocated and some other differences between their studies and ours are that at that time consistent protocols had not been developed for the study of surface light scattering. It was a qualitative diagnosis they did not use a shine fluid camera to measure quantitatively the back scatter and they also used a different method to measure the light transmission and that can induce some variation. I believe they also used a double beam instead of a single beam setup but I'm not sure about that. So our study adds to the growing series of studies showing high levels of surface light scattering in the Acrosoft material. The surface light scattering value levels of other hydrophobic acrylic material analyzed as well as the hydrophilic acrylic PMMA and silicone lenses are comparatively low. Our study did have some limitations one was the unavailability of hydrophilic acrylic and PMMA IOLs for manufacture material and design match controls. The light scattering that we're measuring is back scatter as we're shining the light towards the model and then it's bouncing back into the camera. There are methods to measure forward scatter and so that was one of the limitations that we were only measuring the back scatter. Also light transmission while important does not account for the whole of the visual experience. So further in vitro studies are needed to more completely evaluate the visual quality and visual experience. We're currently working on collaborations to study modulated transfer function and forward light scattering and other measures to better understand the image that's actually being projected through the optic. I'm hearing my references and I'd like to thank Dr. Werner and Dr. Mamelis for this whole year. Dr. Werner has been an incredible mentor working on these projects. It makes me excited about the project too and also very generous with her time to help me. Dr. Mamelis has been an incredible mentor in the clinic with pathology. I've learned a lot of things I never knew existed. Mary Mayfield and the Pathfell have been incredibly welcoming and good friends this year. But not only have they welcomed me to the academic environment here they've also shown me some of the finer points of Utah life. Dr. Werner has introduced me to the joys of Brazilian barbecue and also and of course Costco chocolate cake. Dr. Mamelis took my wife and I up to a park city and introduced us to the mountain biking trails up there in the fall with the beautiful colors. He didn't want me to take a picture of him at the time but later on I snuck a picture of him when he was on one of the harder parts of the trail. It was a picture of Dr. Mamelis in action. Thank you very much. Any questions?