Dr. Hardten: Well, thanks for coming today. I really appreciate it. I'm going to talk about using UBM to maximize IOL outcomes and talk a little bit about the technology, a little bit about the things that we can do in our practices with ultrasound in the 2012 era. There's lots of options for anterior segment imaging, and each of these has its own advantages and disadvantages. So, for example, the most basic technology is the slit lamp examination. We can use photography. Probably topography is what we use most in our practice for imaging anterior segment for things like keratoconus screening, that type of thing. But, other types of imaging of the anterior segment are also important. So, we have corneal tomography. We have ultrasound, which is what we'll talk about mostly here today, and then we have OCT testing. And they each have their own unique advantages and disadvantages.

One of the areas that, in my practice, I deal with a fair amount is phakic IOLs. And so, you heard a lot of other--in some of the other talks here today, you heard a lot about uses of UBM in patients with severe pathology like trauma and issues like glaucoma and corneal tumors or iris angle tumors, ciliary body tumors, that type of thing.

The phakic IOLs are a typical need in a comprehensive ophthalmology practice or a busy refractive practice, and there are some big advantages to UBM. And so, here you see a couple of patients that, with the traditional management options or the traditional measurement options, had complications because of the fact that they had issues with sizing mostly of the phakic IOLs.

And so, on the left-hand side of the screen here, you see a patient that had had a Visian implantation. Here the implant was too long and caused crowding of the anterior chamber angle, high pressure, problems with the endothelium. And so, you can see iris ischemia, some mild cataract, and this patient also has a decreased endothelial cell count.

And that happened despite the fact that the anterior segment clinically looked normal and that central anterior chamber depth was what we would consider adequate, so over three millimeters. And so, we'll talk a little bit about how I use UBM in my practice to try to prevent that type of complication from occurring.

On the other picture here, on the Verisyse image on the right, here again the anterior chamber imaging could help to tell that this patient had a high lens rise, which I'll explain a little bit more in detail here. But, this patient developed posterior synechiae inflammation because the implant basically touches or pushes on that central lens and iris cuff over the lens in that central area, leading to this picture that you see on this right-hand side. So, a lot of this comes from what are suggested safety parameters. Georges Baikoff's been very active in this area because he was first phakic IOL leaders in this field over the last 20 years now. And he described the situation where you want to maintain 1.5 millimeters between the endothelium and other structures. Out at the mid peripheral zone of the iris is where it's most important or most common. And that's very difficult to do if patients have a high crystalline lens rise. And so, if you look at the images where you have this angle out here and kind of draw a line to the other angle, this zone that the lens rises up over, that angle there is that--or that line is what we call the crystalline lens rise.

And so, if that angle is high, then the iris sits up higher. And so, it's more likely to be causing problems with phakic IOLs like the Verisyse implant or the Visian implant because it can cause crowding of the angle and also excessive touch at the cuff of that iris and that area.

And so, how do we image that? How do we look at that? And then, also with phakic IOLs that are in the posterior chamber, how do we actually look at the sulcus? So, you see here on this OCT image, you have no detail or image of the sulcus at all. And that's also important for patients having phakic IOLs.

Now, one of the things that frees us up, in a sense, to use UBM in our practices nowadays has been that UBM has really improved over the last four or five years. We used to have to use a traditional old water bath, and the technician had to worry about this moving up, touching the cornea.

Now, we have better technology now because we have sterile techniques and techniques that can help to keep this nub away from the cornea and still prevent the near-field artifact that occurs with ultrasound, as Tom Prager talked about, but also be convenient for the patient, comfortable for the patients. The patient can sit upright with our current technology. And a lot of that has to do with this little bag or ClearScan that goes over the top of the transducer so that it provides good clearance but also an excellent image of the picture with our modern ultrasound. So, one of the nice things about the Quantel Aviso ultrasound is that it has excellent image quality, is very easy to use, and so you can get accurate information about the sulcus. But, with old traditional water bath technology, it would have been very cumbersome and not widely accepted. So, our technicians now do these scans in our practice. They're--they've really good at it. Even though phakic IOLs is not an enormous number in your practice, it's not like doing A-scans for patients with cataract surgery, but still the technology is easy enough to use that they can get the images and the quality that they want to.

The software is great on the Quantel devices nowadays too. And so, that makes it very easy for our technician--for our technicians. It's also comfortable. And like I mentioned, it's sterile so it really helps that. So, the phakic IOLs, again, we're using these more and more for myopia. There are new IOLs being approved all the time, especially outside of the US. And so, the phakic IOLs, I think, are safer nowadays because of this availability of UBM.

And like I said, the technicians now, the fact that they accept it and will do the testing as opposed to saying, "Well, I'm going to wait for the tech that always does that test" and have them come back on a specific day, we're really able to provide this technology for our patients. So, when we look at IOL planning for either the Verisyse or the Visian, we could potentially just use Scheimpflug or OCT. It's a simple test. It doesn't require a lot of knowledge by the technician. As I mentioned, UBM is now something where the technicians are able to do that technology

But, these are a little simpler. OCT and Scheimpflug are admittedly easier than the UBM to--for the technicians to do. But, the problem is that there's no direct visualization of the sulcus through areas that are pigmented such as the iris, and so it's very difficult to get direct sulcus-to-sulcus measurement. So, you miss things like iris cysts or any of the sulcus abnormalities also. So, our current phakic IOL workup in our practice involves the traditional tests. So, slit lamp examination, A-scan, ultrasound to look at anterior chamber depth, and also have measurements for regular, traditional IOL calculations so that, when they have cataract surgery in 20, 30, 40 years, we have that information. And we do high resolution B-scan ultrasound to also look at that central AC depth, and then we look at the midperipheral AC depth.

So, as I mentioned before, this is sort of the extra safety check that we do nowadays in comparison to the traditional method of just measuring AC depth. And that's looking to make sure that we have adequate room to still have that 1.5 millimeters of clearance that I mentioned earlier in that slide that I showed you about the Georges Baikoff safety aspect, where we want to maintain 1.5 millimeters from the endothelium to whatever other structure is placed in that area, whether it's an implant or the iris that might move further forward.

And so, we check that safety through using Scheimpflug. So, we use the Scheimpflug, and it will look at this midperipheral depth in all areas. And then, we add .5 millimeters to that because that's what the traditional Visian implant will shift the iris forward. Or, the Verisyse implant, that's about the rise that it has off of the iris

But, we'll also do a high-resolution B-scan ultrasound because it is able to image those structures a little bit better. And then, as you see up here in this image, what we do is that we measure that central AC depth from the image and then also look both in the horizontal and the vertical directions at this midperipheral iris area. And we do this at a zone of six millimeters. So, for example here, it's a little bit dim on the image, but you see that it's 2.5 millimeters between the iris and the endothelium. Then, again, when we put an anterior chamber implant it or phakic IOL in, that'll move forward about a half of a millimeter. So, we'll still have two millimeters of clearance, which is adequate for IOL implantation. So, this meets that safety check by you looking at this high resolution UBM. Again, we check this in the horizontal and the vertical directions and record those, measure those, print those out for the chart

The other issue that's probably even more of a sticking point, especially for posterior chamber phakic IOLs, is trying to figure out how the sulcus-to-sulcus measurement figures out into this. The traditional way of trying to estimate the sulcus-to-sulcus dimensions has been through the white-to-white measurement in the horizontal direction.

One of the problems with white-to-white is it's extremely variably related to the sulcus measurements. And so, meaning that some patients have a white-to-white of 11 but their sulcus diameter might be 11.5 or 12, and some might be shorter than that white-to-white measurement.

And that's where high resolution B-scan ultrasound really has a unique advantage compared to white-to-white measurements, compared to OCT testing, or compared to Scheimpflug imaging, is it really can give you true sulcus-to-sulcus dimensions. So, again, we do those scans, and then the technician will measure from one end of the sulcus, as you see here, over to the other end of the sulcus, as you see here. And so--and then, we know that that--what that distance is.

Because most of the data has been based upon white-to-white, we then use this ultrasound number as a double check. If they are within the same range, then we can use--if one's 11.5 and the other one is 11.5, then we know that our number is correct. If it's something where they vary by more than .4 millimeters, then what we'll do is move up or down from the white-to-white measurement towards the ultrasound measurement. So, for example, in this specific patient here, you have 11.64 millimeters for the diameter of that sulcus. And so, if the measurement for the white-to-white had been 11 millimeters, for example, then we'll use 11.5 millimeters for that measurement. That's entered into the software with the STAAR Visian ICL. Same thing if it was something where this--the white-to-white measurement was over 12. We would move down towards that 11.6 millimeter measurement for the phakic IOL in these cases. And with that, there's been a few published papers that really support this notion of leaning towards that sulcus-to-sulcus measurement for these patients and get better IOL sizing with those patients. So, again, it's partly central AC depth, midperipheral AC safety check in a way, and then that sulcus-to-sulcus dimensions. And UBM plays a real important role in that type of patient. This also summarizes it. So, again, what we're trying to do with that ultrasound, it's more versatile, is we are able to obtain the midperipheral iris measurements and then the sulcus-to-sulcus measurements. And as I mentioned, if the white-to-white and the sulcus dimensions off the UBM measure more than .4 millimeters different, then we'll basically move up or down in ICL size in those patients.

The other thing that's important is many patients have asymptomatic iris cysts. So, there may be some other abnormality where, if you put the IOL in that angle or that orientation, then the iris cysts may cause other problems with the IOL. They can cause pigment dispersion. They can cause problems with decentration of the implant. And so, if we know that there are iris cysts in one orientation and not in another, then we might place the implant in a different meridian to try to avoid those cysts in those patients. Here is a patient that has iris cysts. And these are actually quite common even in the asymptomatic patient even when you don't see that on them in slit lamp. We're used to, you know, really large ones like this where they're obvious. But, in just screening normal patients, that's not uncommon to see iris cysts. If we have iris cysts, it's important for us to know where they are located in the area of the eye. And so, we have a standard protocol that our technicians do when we're measuring phakic IOL measurements and even just for general documentation purposes for patients with UBM. And what we do is--and they always do it in exactly the same order so that we know. They do a full scan vertically moving from the right to the left, and then do a full scan horizontally moving from superior to inferior.

And they do that partly for the purposes of the measurement. So, then they can go back and look frame by frame and find the measurement that's the central measurement in each of those scans, and then do those measurements of endothelium to iris or endothelium to angle, and then, in the midperiphery, endothelium to iris, and so--and then also sulcus-to-sulcus in that same picture. And so, that allows us to get those measurements in both a horizontal and a vertical direction with really just two gradual scans across the eye. And then, they're also going to scan for other abnormalities, so looking for iris cysts, which is the main abnormality we ask them to look for. Obviously, in some certain pathology, they might take more images of that pathology. But, they would do this type of scan in every single patient so we have the full information that we need for the eye. And then, they'll go in and, in a sense, hone in on that pathology.

So, then again, as I measured, they'll make those measurements--or mentioned, they'll make those measurements, the AC depth, iris to endothelium at a six-millimeter zone, 45-degree angle, sulcus-to-sulcus, and then print those measurements out. And then, they go in and do this--the planning software on the phakic IOL software, again, moving up or down if there's a variance or a discrepancy between the white-to-white measurement and the measurement based upon the UBM. So, here is an example. This is the same picture I showed you earlier, about a minus 14-diopter myopic female. Here there is adequate 1.5-millimeter safety zone with a .5 millimeter. So, still less than that measurement of this 2.43 out in this area.

Her white-to-white was 11 and sulcus was 11.64. So, we entered 11.5, meaning we moved up a half a millimeter onto the software with the STARR software. And so, then this would indicate a MIC--a ICL 126 for the length of the implant. And she did quite well with her implantation.

So, I'll go through a few other applications that I think are also important and a few cases. Again, this is in a practice that's really--my practice is geared towards cornea, refractive surgery. Probably the biggest, widest use, as you've seen already in Dr. Noecker's [sp] talk, is really glaucoma. It's a huge benefit for glaucoma, lots of pathology in that area.

But, even other than phakic IOLs, I find it useful in my practice. Here is a patient that has a dislocated implant. And so, it's important to know to what degree, are there any other structural abnormalities back behind the iris. This patient has synechiae between the iris and the implant, so you really can't get any visualization of this region out here underneath the iris. And so, with UBM, though, you can analyze that area, make sure there isn't something else going on in that region, and if so, then help you plan preoperatively.

We've also used it in our practice for skin lesions, trying to find the depth of the skin lesion. So, I think there is wide application with UBM for dermatologic/oculoplastic indications. And so, our oculoplastics people will use this for looking at depths of various skin lesions, trying to decide if something is cystic or if it's solid based on the skin.

And again, the technology is easy to use. The quality of the images is really good. And again, with the lack of a water bath, they're using the ClearScan, it's really easy for those technicians, comfortable for the patients.

Here's phakic IOL placement. So, here you see synechiae, an ICL basically with really high vault. And so, again, you can get good images in that area. Here is where a cyst has started to displace an IOL. And so, again it's something where you don't always have visualization of that area, because you have pigmentation on the top. You have synechiae. It may not dilate to that area. So, you can look and see. Is the haptic bent, broken? Is there blood there, tumor there, scar tissue there? It kind of helps you, basically, before you go in and do the actual surgery itself. Here is another image where--the anterior chamber membrane in this area here with some synechiae and very--a very organized type relationship between these tissues in that area. So, again it's helpful before you go in and surgically modify this to look at those

Again, subluxed lenses. This is a higher resolution image of that one picture I showed you earlier. But, here you can see one of the haptics. This is a square edged or a square haptic implant that started to touch the ciliary body nasally. And this patient has uveitis-glaucoma-hyphema syndrome, and so this is obviously also quite important.

This is a patient that we saw that had a failed DSEK that was referred in. And so, one of the questions--now you have this DSEK, you can see it sitting here totally opacified. One of the questions that I had before I was going to go in and re-operate on this patient, is that implant right--still in the right position? How much scar tissue is there between the iris and the implant, the iris capsule? Is there retained cortex?

So, in this area--this case there was actually some retained cortex in one of the meridians. So, how are we going to deal with this patient? So, it's just important in looking at those other structures that you can't visualize with the slit lamp. Certainly you can't--anything you can't visualize with a slit lamp, you usually can't measure with OCT testing or Scheimpflug imaging. And so, that's where UBM comes into play.

So, in summary, I think that UBM is now a very useful tool in our anterior segment practice. Again, a lot of the applications, as you heard from others, are glaucoma, tumors, etc. But, at least in my practice, phakic IOL planning is my number one use for UBM.

And then, other issues like iris cyst determination, again mostly in the phakic IOL patients. But, then other problems like being able to see behind structures to figure out is the implant centered, decentered, present, not present? You know, what's the--what are the issues with--that's going on behind the opaque cornea in the anterior segment? Again, the increased use increases our comfort with the technology and also our ability to detect pathology. And a lot of that's fueled with advancements in the software, the technology, the resolution of the scans compared to 10, 15 years ago, and also patient comfort.

So, thanks for listening. And we really appreciate you listening in on the talk today. Thank you.