Lecture: Corneal Disease and Dystrophy Management

During this live webinar hosted with SightLife, the importance of early intervention and medical management of cornea disease and infection will be discussed. Dr. James Lehmann and Dr. Rahul Pandit will use case studies to discuss the critical nuances for early referral of patients suffering from corneal disease ultimately, leading to better outcomes post-transplant. General ophthalmologists can play an important role in ensuring access to quality follow-up care as well. It’s critical to increase access to corneal care and reinforcing the patient care pathway across all medical cadres for optimal patient outcomes.

Lecturers:

Dr. James Lehmann: Former Orbis staff ophthalmologist (2005) and currently a cornea surgeon at Focal Point Vision in San Antonio, Texas, USA

Dr. Rahul Pandit: Associate Professor of Clinical Ophthalmology at Houston Methodist Eye Associates, Houston, Methodist, USA

Transcript

MS. MAZHAR: Hello, everyone. Thank you so much for joining, wherever you are in the world right now. My name is Nashrah Mazhar, and I work at Sight Life, a non-profit organization that works to eliminate corneal blindness worldwide. We’re fortunate enough to partner with trusted individuals like Orbis to really make our mission of eliminating corneal blindness come true. I wanted to share a little bit of how we do that, and really wanted to open the door of SightLife partnership with yourselves. So thank you for being here. So SightLife works on transforming a landscape in the countries that we work with. And we do this by focusing on five key programs. These key programs really determine the landscape of a country, and the key pieces — the things that are needed to be self-sufficient for that country, to not only meet the needs of their population and their community, but really thrive and bring access to treatment, for the corneally blind community. So one of the programs we have is advocacy and policy. This program works to partner with government, individuals, and key opinion leaders in the country, to develop healthy partnerships, to support the entire health system. Ultimately having the proper policies in place will transform access to care for individual patients. One of the other programs we have is prevention and awareness. Preventative treatment and awareness programs are critical to really be integrated into a health system, as well as school systems, to provide, again, that access to care, but really, early identification of disease, at a very grass roots level. So this is happening in the communities with individual female community health workers. One of our other programs that I will speak a little bit more to is clinical training. This provides specialized health care providers with the proper skill sets to be not only — open up their capability, but also open up their ability to see patients from all different areas, to provide the best cornea care that they can. Our eye banking development program helps individual eye banks in the country find the best practices to really be high functioning and efficient, so that the rates of tissue and the quality of tissue for those transplantations is the best it can be. And lastly, we have innovation. Innovation is a critical program to really help not only health care professionals, but individuals in the entire industry have access to affordable treatment solutions and innovation to improve the overall patient care experience, and ensure timely treatment. This is what a healthy system looks like. And so our goal to really eliminate corneal blindness is to meet the needs and transform those health systems. Specifically, I wanted to talk to everyone here about clinical training. SightLife doesn’t do the sight restoring surgery. What we do with this program is make it more possible to have those sight restoring surgeries happen, and patients be identified earlier, and getting that care that they need, so that they’re not progressing in their disease. We’ve been in partnership with Orbis and been able to do this for a number of years, but we’ve trained more than 1400 ophthalmologists. We want to make sure that not only corneal surgeons, but general ophthalmologists and other ophthalmic professionals, such as optometrists or allied ophthalmic personnel, have the skill sets that they need to help create a seamless patient experience, across every center. So primary, secondary, and tertiary centers can really be supplemented with the proper care that they need to provide their patients. I’m lucky enough to be able to offer everyone here a wonderful partnership with our international faculty, and so down the line, in your career, as you continue to need that mentorship, we have individuals like Dr. James Lehmann and Dr. Rahul Pandit who are phenomenal coaches and mentors, who can really help meet the need for corneal surgeons, but also general ophthalmologists. So thank you so much for being here. Please know that we are ultimately a resource for you. So my contact information is here. I’m happy to answer any questions that you may have about transforming your specific health system, but really getting access to that education you might need, to be the best health care provider you can be for your patients. But it’s my pleasure to introduce Dr. James Lehmann and Dr. Rahul Pandit, and begin this webinar. Thank you so much. DR LEHMANN: Thank you, Nashrah. I want to share my screen now, and we’ll start the talk. Okay. So everybody can see my screen? Good. So I’m Dr. James Lehmann. I’m gonna talk for the first half of the webinar, and then we’re gonna turn it over to Dr. Pandit. You can send questions via the Q and A and we can answer during the talk, either via typing or I can bring it in and we’ll talk about it together. I’m visiting with you all from San Antonio, Texas, where I’m in private practice as a cornea and cataract doc, and I’ve had the opportunity to do about 20 trips over the last five years with Orbis and with SightLife. We’re gonna be talking about specific corneal diseases today, I’m gonna focus on corneal ulcers, case studies, and of course, we know the histology of the cornea, the epithelium, the stroma, et cetera. Like I said, there’s different types of corneal disease. Infectious, inflammatory, inherited, degenerative, and traumatic, and today I’m gonna be focusing more on the top two, and then Dr. Pandit is gonna be taking the other three. So we’re gonna jump right in, and we’re gonna use a case format here. And I chose cases that have — some of them have some diagnostic dilemmas, and I also decided to choose these cases because, when we teach, we get a lot of questions. Dr. Pandit and I were in China back in November, and we did a class for about 60 ophthalmologists, and we got a lot of questions that we’re gonna tie into these cases. So the first case is a 30-year-old male who complained of pain, sensitivity to light, and decreased vision, and he wears contact lenses. Soft contact lenses. So we’re gonna go to the next slide here. And we have a question for you all in the audience. So what would be the best management of this ulcer? We want to start an hourly fluoroquinolone, we want to start hourly fortified antibiotics, you want to start a topical steroid, or do you want to tap the vitreous and inject antibiotics and steroids? You’ll have about 30 seconds here. So go ahead and submit your answer. And then Lawrence with Orbis will post the results, and we’ll continue. But you can see here from the picture we have injection of the conjunctiva. There’s about a 3×3 millimeter corneal infiltrate and hypopyon in the anterior chamber. Results of the poll show starting an hourly fluoroquinolone and starting an hourly fortified antibiotics are the top two. That’s good. On the right track there. This is a bacterial ulcer. The key presenting clues are that it happened fast, it’s acutely painful, and in this case, it’s purulent. You have the hypopyon, mucus and debris on the surface of the cornea, and this happens over 24 hours. In the United States, most of these are contact lens-related. However, I know that’s not the case in other countries, where trauma might be the most common reason. In the United States, about 90% of the ulcers that we deal with are bacterial, not necessarily fungal like in the developing world. I’m gonna talk about fungal later, but right now, this is how it presents for us. And so in our differential diagnosis, we have to be thinking of bacterial, fungal, viral, and acanthamoeba. And so you ask questions about how they got the ulcer. And so most people will tell you that the eye started hurting one night. And then they woke up in the morning with a lot of pain and a red eye, and they come see us that day or the next day. The workup is basically — doing a culture. And then in America, we don’t plate them anymore. We used to do a scrape and plate them on chocolate, blood, and Sabouraud, but now we send it to the lab, and they’ll culture fungal and bacterial for us. It’s rare now that we get Gram stains. We used to have those more commonly. We also don’t use PCR routinely yet, which will be helpful in the future. For now, it’s a culture. And in this case, I agree. Starting with hourly fortifieds. For us, that means vancomycin and tobramycin. In my practice, it would be 25 milligrams per milliliter of the vancomycin and 20 milligrams per milliliter of the tobramycin, every hour from 8 am to 10 am. I would not start a steroid in this patient in the active infection. You don’t know if it’s fungal, and if it’s fungal, you can make it spread faster. I would wait until they’re recovering and then add a steroid. There was a trial about five years ago, looking at using a steroid from the beginning, with bacterial ulcers, and they found no steroid benefit. So again, in this case, I would start fortified antibiotics, vancomycin, tobramycin, I would perform a culture, and do follow-up in 24 to 48 hours. I actually err more towards 48 hours, because you don’t see much improvement in 24 hours. Like, seeing the patient the next day is fine. But if you can stretch it out another day, you can actually see some benefit. I like to tell patients, they’re not gonna start feeling better. I’m gonna see that it’s not getting worse. Tell them it’s like a train. A train doesn’t just stop and then go backwards. It has to slow down and then go backwards and get better. In this case, I tell them: I’m gonna see that it’s not getting worse, and that’s gonna tell us that it’s getting better. Just a key point there. I’ll go to the next slide. Most of the ulcers we deal with are pseudomonas, staph, and strep. Here’s another presentation of an ulcer. Again, you see mucus and purulent area, but even though this looks like a classic pseudomonas ulcer, you can’t just know that’s the case and put the patient on a drop that only kills Gram negative bacteria. You still have to treat them with fortified antibiotics, using the vancomycin to cover Gram positive. So one of my colleagues told me this rule that he learned in residency. They called it the 3-2-1 rule. And the way that it works is if you’re a general ophthalmologist, this is a helpful thing, or an optometrist, a helpful thing to know when to treat and when to refer. If you see a patient with an ulcer similar to this picture, small, but the eye doesn’t look too angry, you can do a fourth generation fluoroquinolone every hour and see the patient back. Okay? However, the time to refer would be if it’s within 3 millimeters of the central visual axis, if the infiltrate is larger than 2 millimeters, or there’s a large anterior chamber reaction. 1 plus cell or greater. If none of these criteria are met, the 3,2,1 rule, it’s reasonable to go ahead and start a fourth generation fluoroquinolone and not necessarily refer to a cornea specialist. However, if they’re not getting better, then it would be time to refer. So again, the 3,2,1 rule. Within the central visual axis, 2 millimeter plus, or 1 plus cell or greater. Now, trauma, vegetable matter, these things make it important to refer to a corneal specialist, or if you don’t have a specialist to refer to, to consider fungal or other etiologies. I just got a question here — the question was how long do you keep the bacterial ulcers on hourly antibiotics? Until they start improving. Okay? And so that could be two days, it could be four days. If you have them on fortified antibiotics and they’re not getting better after 4 to 5 days, you have to find out if they’re using their drops as you instructed. If not, you don’t have any data to make a change in your treatment regimen. But if they’re not getting better and you know that they’re using the drops, because they bring them in and show you the bottle, you have to consider other etiologies in that case. I would probably do a confocal microscope, microscopy, I would start treating for fungal, consider acanthamoeba. So atypical ulcers. This is a picture of a patient who had LASIK, and they developed an infection under the flap. You can see an edge right here. But it’s chronic. You can see the blood vessels going there. These can sometimes be resistant bugs, they can be strange bugs that you’re not used to seeing. And they require special culture mediums. So in this case, if there’s an ulcer on the surface and it’s not just under a flap, you can use a culture, but you have to use special media like the Lowenstein-Jensen agar, and special meds such as amikacin to kill these bugs. If they’re not getting better or it’s a history of surgery like LASIK or crosslinking, you have to think outside the box and it’s not just a trauma or contact lens ulcer. Someone asks: Is it okay if I give topical antibiotics like gentamicin or fluoroquinolone for ulcer with hypopyon? I guess what she’s saying is: What if I don’t have fortified antibiotics? What can I use? If you don’t have fortified antibiotics, you need to put them on something. You also can ask your hospital about patterns of bacterial resistance, and get a better idea about what medicines to use. Sometimes you can use older antibiotics. Such as chloramphenicol, gentamicin, and polymyxin, to treat ulcers, because there may be more resistance to fluoroquinolones. Okay? And so that’s a very local type question. I would say you can get the data about resistance from your local hospital, and you can also, if you don’t have the fortifieds, you can use some maybe older generation antibiotics. Especially for staph aureus. Which can be sensitive to the fluoroquinolones. And then anonymous attendee asked: Is it standard to use cycloplegics for all corneal ulcers? I do not necessarily do so. You can, though. There’s not a problem. If the patient can’t even have the lights on in the room, it’s a good thing to do. So there’s no problem using that. Sometimes they’re overwhelmed with drops, and if you’re adding more drops, it can be a problem. Okay. We continue. Here’s another ulcer. This is one in a LASIK flap again. Kind of a unique situation. This is like a chronic ulcer as well. This is not necessarily an ulcer, but almost like a Salzmann nodule that developed when some flap abnormalities happened. You can tell there’s no blood vessels to it and it doesn’t look very infectious. This is something I would kind of observe or maybe peel and see how well it healed. Okay. Fungal ulcers. So for you all in the developing world, especially in the subcontinent, this is what you see most of the time. A big scary ulcer. It’s a farmer who came in, four days later, and they come in with a nasty ulcer like this and a hypopyon. In this case, the patient is gonna require therapeutic keratoplasty. In America, however, in Europe and South America, sometimes we don’t see such large fungal ulcers presenting. And so for us, fungal ulcers normally kind of come to our brain when they’re unresponsive to antibiotics. Appearance is a trick. To see an ulcer and say whether it’s fungal or it’s bacterial — you can’t do it. You can be 50%. It’s like flipping a coin. Clues are things like a history of trauma, steroid use from a referring doc, or maybe they didn’t get better on the antibiotics. Those are more useful to know whether it’s gonna be a fungal ulcer. And the first line treatment is natamycin. Cultures are critical, because especially if they’re unresponsive to the natamycin, you have to know what kind of fungus it is. There’s so many you can’t even name them, and new ones being discovered every month, and many of them are resistant to even the strongest antifungal medicine we have. There’s basically two or three families. One is responsive to natamycin, one voriconazole, and one amphotericin. So the candida are normally responsive to amphotericin, the filamentous, either natamycin or voriconazole. A few other questions here. So back to bacterial, if I run the culture, should I stop the topical antibiotics? And if so, how long do I stop before I run the culture? I guess you’re saying the patient is being referred in. They’re already on antibiotic drops. Is it worth doing the culture, or do you stop it? No, don’t stop it. Just do the culture and get what you can. However, if you have a patient that’s three weeks, and you can’t figure out what’s going on, it may be worthwhile to stop the antibiotics or antifungals for a little bit, and repeat the culture. But it’s better to start treating them with the appropriate medications than stop the medicine to get a culture. And then Dr. Pratiwi asks: Hi, how can we differentiate haze from infiltrate? Infiltrate is normally gonna have an epithelial overlying it that will stain with fluorescein. You can have strictly a stromal infiltrate, but that’s gonna be rare. That’s more of an inflammatory type etiology. With a fungus or bacteria, it has to penetrate through the epithelium. That is not always the case, but that’s generally a rule of thumb. So haze is gonna be — you’re gonna be able to see it. It won’t be quite as dense, and it’s not gonna be the eye is inflamed or things like that. There are some infiltrates that are inflammatory that can happen with tight contact lenses, after crosslinking, and that’s much trickier. In this case, you have to start with antibiotics before you treat with antiinflammatories. And then Dr. Kalipatnapu asks: In the early stages of suppurative keratitis, do you use carbolic cautery to remove slough? You can use a Weck-Cel or a cotton swab to remove some of the mucus, especially on fungal ulcers when you need to remove epithelium for the drops to penetrate. But I don’t think you need to use cautery to do that. However, I guess it would depend on the case. Just with gentle debridement, generally you can get that. And another doctor asks: Considering Boston Kpro prosthesis might help? The Kpro comes in later. That’s when you have a fungal ulcer, you do a therapeutic keratoplasty if required first, and then you come back and do an optical keratoplasty. And if that fails, then you would do a Kpro. A Kpro has its own range of problems, and it’s not indicated in a patient who has a good other eye, and they have a fungal keratitis. The eye has to have failed, honestly, in my opinion, I prefer — they’re binocularly blind before doing a Kpro. You definitely wouldn’t do it in an acute phase. And Dr. Saito asks: Would you consider anterior segment OCT to evaluate the extent of the ulcer and depth? You can, absolutely. Especially if they’re kind of impending perforation. But most of the time, visually, you can see when they get to a Descemetocele type thing. But it looks good in presentations and it’s good to educate the patient. I have no problem with OCTs to evaluate the depth. And if there’s no natamycin available, what can we give first line? You give what you’ve got. Amphotericin, voriconazole, those may be more readily available. Dr. Charangee asks how to manage a persistent epithelial defect. Dr. Pandit will get to that later. Role of subconjunctival antibiotics. Can it be more effective than hourly topical? No, for corneal ulcers, because subconj antibiotics are helpful when people have blebitis that can lead to endophthalmitis. It’s helpful for that. But they can have contact lens lavage. A doctor in Arizona likes to publish a lot — in China, they do contact lens lavage. A setup where they can put moxifloxacin through a contact lens setup. But I don’t have that in my clinic. Dr. Pal asks: What conditions can we use sodium chloride? That’s more for corneal edema, I would say. Not necessarily for ulcers. Dr. Saito asks: What about povidone-iodine 5% in unresponsive ulcers? Yes, sure. But 5% may be too strong. That’s pretty painful for patients. It will kill a lot of things, even viruses. So you could do that if you didn’t have anything else. I maybe would go down to 2%. It’s gonna be pretty traumatic to the patient to keep putting in drops of 5%. Dr. Nova asks: When should we use oral antifungals? The MUTT trial, Dr. Prajnah in Aravind Eye Center looked at the role of oral voriconazole in patients. They mostly have filamentous fungi there, not necessarily the candida, but they didn’t show improvement in patients who took oral voriconazole. Do you give steroids with fungal keratitis? No. Generally with fungus it makes it spread. I’ll continue a little here so I don’t take up too much time. I’m actually running behind. Confocal microscopy can be helpful to differentiate between fungus and acanthamoeba. When you see filaments like this, it can be helpful, if you’re having a diagnostic dilemma. And then these are some pictures of cysts and trophozoites associated with acanthamoeba. You see a double walled cyst and a well delineated line. These are corneal nerves found right under the epithelium, between the epithelium and the stroma. And acanthamoeba likes to eat nerves. So you can see pictures of cysts around the nerves. So the second case is another 30-year-old male, complaining of pain, sensitivity to light, and decreased vision, and you see here this classic picture. So we’re gonna have another question for the audience. What’s the best management of this patient? Do we want to start hourly moxi and see them in one to two days? Steroid and oral Valtrex? Topical antiviral, or just a steroid with topical antiviral? Some diagnostic dilemmas here. Put your answer, and Lawrence will post the results of that poll. Half the audience wanted to start a topical antiviral. That’s the correct thing. What differentiates HSV keratitis from a bacterial ulcer? It’s more gradual onset with minimal pain, but they’ll have photophobia and decrease in vision. It’s not contact lens and can affect people of any age of. * in terms of differential diagnosis, when you put dye in and see a classic lesion like this, it’s HSV, zoster, or an abrasion. A helpful tip: Some people can get corneal abrasion and have the same symptoms, and when it’s healing, it looks like a dendrite. So if you put a topical anesthetic in and get a cotton swab, you can gently touch the edges of the lesion, and in a dendritic lesion, you won’t move them. But if it’s an abrasion, you can easily peel them away and then you know it’s more of an abrasion than a dendrite. It gets rid of that pattern. So that’s a helpful thing to differentiate. Generally a workup is not needed. 90% of the world has antibodies to this, so you’re not gonna have any help with any kind of serology. And the treatment is a topical antiviral for five days, either ganciclovir, trifluridine, acyclovir, whatever is available in your country. Generally a steroid is not indicated if the epithelium has been ulcerated, and the follow-up is about 3 to 5 days. Fortunately it’s a self-limiting disease. Here’s a picture of a patient I had that was placed on steroids, and you can see the dendrite starts to spread and get deeper. So we don’t want to use steroids. Now, endothelial — endotheliitis also presents with gradual onset, but it has severe decrease in vision, photophobia, and happens over several weeks. It’s corneal edema for no obvious reason. If the patient has never had ocular surgery and presents with this picture, it’s HSV. But it could be zoster, uveitis, idiopathic, angle closure. Sometimes you have to do workup for the uveitis side, but that’s if they don’t respond to treatment for the HSV endotheliitis. So the treatment for this is an oral antiviral with a steroid. Okay? So the steroid can be topical or oral. Now, this is assuming there’s no ulceration on the epithelium. But you have to cover them with oral antiviral. Valacyclovir or acyclovir at appropriate dosage, and the steroid is the key. That’s gonna help them get better. You may need to treat them a lot longer and taper the steroid a lot longer in these situations. And if they don’t improve on this treatment, you have to do lab workup and figure out what’s going on. But it would be very rare that they didn’t improve on steroids with coverage for valacyclovir. And the last is stromal keratitis HSV. Gradual onset, severe photophobia, stromal haze, and inflamed eye. And the treatment here is gonna be oral coverage with a topical steroid. The follow-up is the same as with the endothelial disease, which is about a week. And this is a case where the patient had previous stromal HSV, and a recurrence of a dendrite. Again, when you have a dendrite, you want to touch it, make sure it’s not an epi defect or an abrasion. And you can’t put them on steroids. You need to cover them first and get this to heal, and once the dendrite is healed, then you can treat them with the steroid. So in summary, with the HSV, if the epithelium is involved, then you don’t want to use a steroid, until you get it to heal. So everybody always asks: When do you use steroids? When do you use oral? Basically you use steroids if the epithelium is healed. But if there’s an epithelial defect, no steroids. And then the stromal and endothelial disease is much more serious. You need to treat longer and you need to use, like I said, a topical steroid and oral antiviral. And the last question is: Who takes prophylaxis? Who do you give oral Valtrex to afterwards? And in my clinic, it’s those that have multiple episodes, mostly the stromal and endothelial folks. Not necessarily the epithelial folks. Okay. And I kind of got behind. I’m sorry. I rambled too long. This is a third case. I’ll just do these briefly. Again, the same complaint, which was a male at 30 years old, complaining of pain, sensitivity to light, and decreased vision. You can see the picture here. And what do we want to do in this condition? Number one, start topical antibiotics, cycloplegic hypertonic, start oral steroids, inject a bubble in the AC, or do a penetrating keratoplasty. Submit your answer, I’ll talk about five more minutes, and then give 30 minutes to Dr. Pandit. Okay. Eye drops, this presents acutely, have a history of keratoconus or ectasia. We don’t have too much of this here in the United States, but there’s data about injecting FS6 gas. You need to do PI. It’s a self-limiting disease, but if the patient isn’t resolving after a few weeks, you would consider that. I would see the patient in 7 days. Definitely don’t want to do a transplant. These patients do better, have less steepening after the scarring. So our treatment for keratoconus is if they have good vision and mild disease, we do crosslinking, if they have bad vision and moderate disease, we do rings, which in America would be Intacs, and if they have bad vision with bad topography, we would do DALK or PK. And my last case, this is a 57-year-old complaining of pain, sensitivity to light, and decreased vision. You can see here this area superiorly. So let’s get an answer to this. Topical antivirals? Oral steroids? Inject a bubble in the AC, do an emergent penetrating keratoplasty? Okay. Go ahead and submit your answers and Lawrence will post the results here. Half of you say start oral steroids, half say topical antivirals. This is peripheral ulcerative keratitis. You can see there’s a gutter that stains, epi defect in this region. This normally is an insidious onset, two weeks, maybe a week or two of increasing pain, decreasing vision, photophobia, and generally this happens in patients with systemic autoimmune disease. Like lupus. There’s a huge differential diagnosis. The main thing is… You have to distinguish it from a non-inflammatory degeneration like Terrien’s. But I do a lab workup, includes complete blood cell count, metabolic panel, urinalysis, ANA, ANCA panel, and syphilis testing and hep C testing. You want to cover them with an antibiotic topically and put them on an oral steroid. Once the epithelium heals, then you can taper the oral steroid and start a topical steroid, and that generally gets them under control, and then they go back to their rheumatologist and you have them maybe increase whatever systemic autoimmune medicine they’re taking. So I’ll turn it over to Dr. Pandit. Thank you very much for your attention. DR PANDIT: Well, thanks, Dr. Lehmann. That was great. I’m gonna get my screen loaded up here. And great. Hopefully everyone can see that. So we’re gonna take this on. And try to answer as many questions as we can. Which — you guys are asking some great questions. I’m trying to type some in, and Dr. Lehmann, feel free to type answers, if you see me not talking about that in the talk. But we’ll try to address it here live as well, as much as we can. We’re gonna take you through cornea diseases, but looking at it in a slightly different way. You can talk about different types of conditions, which Dr. Lehmann outlined really well, and honestly, that’s usually how I think about it. But another way of thinking about it is also anatomically, where we talk about the five traditional layers of the cornea. Where we have the epithelium and Bowman’s, which are often grouped together in terms of diseases, stroma, and then Descemet’s and endothelium, which again are usually grouped together in terms of diseases and etiologies. So if we talk about the common corneal diseases and dystrophies, dystrophies being inherited, diseases being of course things that you acquire, and of course degenerations, which are not really diseases, but common things that can occur that can cause problems on the cornea, we have our group of primary conditions, which we’ll outline here, anterior corneal diseases — we talk about ocular surface disease, which includes a lot of things, dry eye, blepharitis, allergies, even a bit of infection, and then one of our common conditions, epithelial or anterior basement membrane dystrophy, some of our less common diseases, Reis Buckler and Thiel-Behnke, we also have recurrent erosion syndrome, Salzmann’s nodular degeneration, superficial punctate keratitis, which can occur on its own or after infection, band keratopathy, and limbal stem cell deficiency, where the epithelium does not heal because there are not good stem cells in the periphery of the cornea. And then we have our common stromal corneal dystrophies, macular, granular, and lattice, and in the US, we don’t have a high preponderance of these, so we won’t talk too much about this today. And then finally our endothelial or posterior corneal dystrophies, including Fuch’s corneal dystrophy, and postoperative corneal edema, pseudophakic and aphakic bullous keratopathy being the most common, as well as less common posterior polymorphous dystrophy. And we have a whole host of less common corneal diseases and dystrophies, and we’re not gonna talk about this, but just to show you all, these are really interesting, and when you see these in your clinic, it’s often nice to look back in your tables and notes and just say — oh yeah, I just saw a little bit of peripheral dystrophy and kind of explain to your patient what they have going on, but understanding that it’s probably not a significant condition. So here’s the first poll question. Which of the following anterior corneal dystrophies is pictured here? We have four options. Epithelial or anterior basement membrane dystrophy, Salzmann’s nodular degeneration, recurrent erosion syndrome, and band keratopathy. this is a 30-year-old male with chronic irritation in his left eye and difficulty opening his eye in the mornings, with pain upon waking up. One week ago, woke up with severe pain in his eye, which took several hours to recover. Recurrent erosion syndrome. We know these corneas don’t fully heal, and the basement membrane is damaged in these post-traumatic eyes. DR LEHMANN: I’m sorry to interrupt you. Can you go to the slide show version, where you’re showing the whole screen? They’re seeing the presenter version. DR PANDIT: Got it. Thanks for letting me know. DR LEHMANN: Sorry to bother you. >> You can click on display settings on the top, Dr. Pandit, and you should be able to stop it. DR PANDIT: Let’s see here. I apologize for that. Thanks for letting me know. Let’s just go to… Well… I seem to be frozen here. James, if you want to turn on yours, I’m happy to kind of have you forward. DR MAZHAR: You’re on mute. DR PANDIT: It’s now frozen. I apologize. DR LEHMANN: Stop sharing your screen and I’ll share mine. Okay? DR PANDIT: I apologize. My computer seems to be a bit frozen here. DR LEHMANN: Is this working? Can you see this? Is it looking good? DR PANDIT: I can’t see. There we go. >> I can pull it up here. I think you’re on slide 37. DR LEHMANN: Do you want me to share? Are you gonna share, Lawrence? >> It’s up to you. I don’t mind. DR LEHMANN: Okay. Go ahead and you do it, Lawrence. DR PANDIT: Yeah. Thanks for pointing that out. Sorry about the delay there, but we’ll get back on track. This is a 67-year-old male presenting with cataract surgery, complaints of intermittent blurriness and monocular diplopia. So we won’t necessarily throw poll questions for these, but first of all, what’s your diagnosis? What tests will you use to determine — confirm your diagnosis, and how would you manage this patient? What would you recommend? If you look carefully in the center of the cornea, you’ll see the irregularities that are highlighted, and you’ll notice they’re central, so we presume they’re affecting the patient’s vision. If we show you on the next slide, what we’re dealing with is… If we go back to the previous slide, what we’re dealing with is anterior basement membrane dystrophy, which is highlighted by these irregular, as we call it, map-dot-fingerprint changes in the cornea. And that’s the secondary name we use for this condition. That can lead to a lot of irregularities in the cornea, but also impair the ability to get good accurate measurements when we’re planning cataract surgery for these patients. So when these findings are peripheral in the cornea and we don’t feel that they’re impacting their vision, it would be reasonable to proceed with cataract surgery evaluation, doing all the preoperative measurements, but in cases like this, where they are central, we know it’s more than likely to have an impact on their vision if it isn’t already, so we recommend them to undergo a treatment for this condition, which can help get better preoperative keratometry measurements for planning for cataract surgery, but also just help with their overall visual symptoms, which include the blurriness and monocular diplopia. And most commonly the treatment for this severity of disease right in the center of the cornea would be a superficial keratectomy or polishing of the cornea to remove those irregularities. And waiting for a few months at least before obtaining stable corneal measurements to plan for cataract surgery. You can show the next slide, where we have a 59-year-old male, with a 30-year history of contact lens wear. And complaining of chronic redness and irritation. Once again, you know, with the questions on the top right, you’ll see that we’re looking at these peripheral superior as well as extending into the central visual axis whitish-grayish opacities, which appear elevated on the slit beam view. So if we’re looking at this, the most likely diagnosis, especially in a patient with a history of contact lens wear, often gas permeable contact lenses, is Salzmann’s nodular or corneal degeneration. That would be another term for it, because these are not always nodular in appearance. In this case, these are elevated, subepithelium, but anterior to Bowman’s layer, and can be removed very easily with a superficial keratectomy and in particular peeling the nodules. This is important, because not only can it help with overall ocular irritation, but it also helps once again, if you’re considering cataract surgery in an older patient, you definitely need to remove these to get good stable cornea readings prior to cataract surgery. And in the next slide, we can talk about a poll question here, so we’ll talk about the patient case here, before I read out the questions to you. This is a 58-year-old male, patient who had LASIK ten years ago, and an enhancement done eight years ago, and he complains of progressive blurriness of vision, with significant increase in eyeglass prescription. But she hasn’t seen her doctor in three years. So the poll question will be: What is your diagnosis? Epithelial basement membrane dystrophy, Salzmann’s nodular degeneration, delayed onset atypical bacterial infection, such as mycobacteria, or epithelial ingrowth. And when we have enough answers, Lawrence can put up the poll answers. So epithelial ingrowth. You can see this is quite an advanced case, where you have it extending into the visual axis. I observed this patient, because it in retrospect had been mentioned to her in the past and we were following it very closely. She wasn’t currently having significant enough visual symptoms to want to undergo a repeat treatment. We all know that flap lifting and debridement of the epithelial cells can lead to the potential for further epithelial ingrowth. All this has to be weighed against the propensity for these cells to continue to grow and cause further issues, so you definitely want to treat it before it starts to affect their vision significantly. The next slide… 58-year-old female with a history of quiet proliferative diabetic retinopathy, neovascular glaucoma, peripheral vascular disease, and end stage renal disease on hemodialysis. So obviously a patient with a lot of systemic comorbidities, as well as a lot of ocular issues, complains of glare and gradual fogginess in her vision, with only occasional discomfort. So once again: What is your diagnosis, and do you need any testing to confirm your diagnosis or aid in your management? So in this case, you can see these whitish opacities, spread across the cornea. These typically occur in the palpebral fissure from nasal to temporal but can extend across the superior and inferior cornea as well in more severe cases. A lot of times these cases of band keratopathy can lead to spontaneous visual field defects and a recurrent erosion syndrome picture, where the patient is having a lot of issues with pain and discomfort. This patient of mine wasn’t actually having a lot of pain and discomfort, but was bothered by this whitish appearance in her cornea. 50-year-old female with about 20/80 vision in the other eye, and this eye was limited to hand motions. Prior to the extent of band keratopathy had counting fingers vision, and for her, that was a significant decrease in peripheral vision in this left eye, so she opted to have a treatment for this. The treatment for removing calcification on the cornea is EDTA chelation, you do superficial keratectomy by removing the epithelium, and use EDTA soaked swabs, Weck-Cel spheres, or a well that has EDTA in it, that allows it to sit on the cornea and soak in for several minutes, and then you scrub with Weck-Cel spheres to remove the calcification. Next slide. Another poll question. I’ll read the history first. This is a 71-year-old female with foggy vision and colored haloes around her eyes, presents with difficulty seeing at night, has a little relief from eye drops, and if you look at the slit beam carefully, you’ll see what we’re trying to point out here. Which of the following endothelial diseases is this picture? Fuchs endothelial corneal dystrophy, pseudophakic/aphakic bullous keratopathy, or posterior polymorphous dystrophy? We’ll give a second and then Lawrence, you can pull up the answers. And there we go. I think most of you got the answer correctly. You can see sort of the beaten bronze metal appearance to the posterior cornea, which is classic, pathognomonic for this condition. If we go to the next slide, we see that Fuchs endothelial corneal dystrophy is the most common corneal dystrophy requiring transplantation. It’s autosomal dominant with variable expressivity, and females tend to have it more than males. The classic appearance are these guttae, the excrescences on the Descemet’s membrane. You can see in the up close image and the slit beam on the right. These can be seen in more than just Fuchs cases. In milder cases, a lot of times these don’t lead to any problems. 11% of people over 50 can have guttae, we see this, monitor them, and tell them they may be at risk for corneal endothelial disease in the future, and we can do more testing, such as specular microscopy and endothelial cell counts. Next slide. This is a 71-year-old male who had complicated cataract surgery 12 months ago. States that his vision never fully recovered after surgery. Complains of blurry vision and occasional foreign body sensation. So once again, the cue questions on the bottom left: If you look at the slit beam on the right, you’ll see first of all that there’s a haziness throughout the cornea. We don’t really definitely see Descemet’s folds per se in this slit beam, but you can see there’s diffuse epithelial edema. You can see the microcysts to the left of the beam. Those are best seen to the left of your light beam when you’re shining your light on the cornea. Like internal reflectance on the epithelium. And you can see larger epithelial cyst,s cysts, microbullae, next to your slit beam as well. This is a classic description of pseudophakic bullous keratopathy, similar to aphakic, where you have corneal edema after cataract surgery or perhaps complicated cataract surgery or a patient who’s had multiple other surgeries leading to this corneal decompensation from endothelial cell damage. Next slide. The common treatment for these conditions now is endothelial keratoplasty. And this is the type of stuff that Dr. Lehmann and I and many other surgeons that work with SightLife and Orbis do help teach in courses. Live and perhaps now more virtual for a little while, talking about how we can treat these cases with more advanced endothelial keratoplasty techniques, which saves the patient from penetrating keratoplasty and all the risks associated with a full procedure like that. The main advantages of DSEK and DMEK, Descemet membrane endothelial keratoplasty, over a full thickness penetrating keratoplasty are that it’s faster recovery with less risk of rejection, and you don’t have the large 360 degree wound in the eye, which makes them perpetually weak in the eye and makes them more susceptible to things such as falls and accidents in the future. There is more early management in these cases. You may have to go back and inject more gas bubbles, as you can see on the bottom left. In a postoperative patient of mine, gas bubble, keeping the endothelial graft in place. If the grafts start to dislodge, you may have to inject more gas. The bottom left picture was a patient with DSEK and bottom right are patients with DMEK. You can see on the bottom right there, if you look in the smaller image, anterior segment OCT, all you see are the membranes that you transplant. Whereas in the DMEK, you transplant Descemet’s membrane and endothelial cells with a bit of stroma. That’s the big difference. In studies, with DMEK versus DSEK, there is slightly less rejection with DMEK over DSEK, due to the decreased thickness and less stroma involved in DMEK tissue. There are less refractive changes in DMEK as well, because you’re doing less additive change, less addition of cornea to the patient’s cornea, but there may be less success in complicated eyes, especially with tube shunts, in DMEK. Next slide. This is a 48-year-old male with a history of corneal transplant, six months ago, one week history of photophobia and worsening vision, current drops are prednisolone once a day and dorzolamide timolol twice a day to control preexisting glaucoma. So you look here and you see that this patient is only six months posttransplant, penetrating keratoplasty, in a young patient whose immune system is revved up and only on prednisolone once a day, a classic example of tapering the steroid too early, and causing graft rejection. So this patient needs to be on longer and stronger steroids, more than six months outpatient, because not only do you have to treat their corneal transplant, but you have to deal with the active rejection going on. There’s a loose suture superiorly, and that can trigger rejection as well, by causing ingrowth of blood vessels to the loose suture. So you definitely want to remove that as well. Next slide. This is a 62-year-old male. With a history of corneal transplant, three years ago, and you can see one loose suture was removed, three days ago by my partner, and she started him on topical antibiotics, because she was concerned about this one region there. And you can see a persistent white spot on the cornea. When I saw him, this is how it looked like on day one, with a little bit of an epithelial defect in that area, but that white spot really did not look to be much improved. So again, what’s your diagnosis? You’re certainly concerned about corneal infection, infiltrate, in some cases, even a suture abscess, can be present, in which case, you need to take active management of this cornea with procedures to remove the abscess, and certainly in the case of the suture, if you’re concerned about it at the time of suture removal, you can certainly send that for cultures as well. So again, how would you manage this? Well, depending on the severity of the infection, whether you think it’s just an infiltrate, whether you think it’s an abscess, you need to either treat with topical therapy, after doing appropriate cultures, or invasively removing the abscess or draining it. Next slide? This is a 50-year-old female who I operated on seven weeks ago. She was doing well for the first six weeks, until a few days ago, when she complained of two days of whitish blurry vision. She may have rubbed her eye gently when she was outdoors, and she does spend a lot of time outdoors, currently on Durezol, four times a day in the left eye and Combigan in the right eye. She had a tube shunt, which propelled the graft rejection from her first transplant. That’s why she’s on a higher course of Durezol. So what’s your diagnosis and what tests would you use to manage? And in this case, the tests would actually be quite easy. If you see here, you can see that there’s definitely Descemet’s folds, and if you look closely at this patient’s eye, you can see diffuse white blood cell recruitment in the cornea. And so you’re definitely concerned about graft rejection in this case. Despite being on Durezol four times a day, perhaps something outdoors triggered her eye, but then the other thing you always have to consider, if you look at the next slide, you actually couldn’t see this patient’s epithelial defect very well, at a slit lamp exam, without staining. Usually you can see that very well. But I was actually deceased. When I put fluorescein in the eye, there was diffuse epithelial defect. And when I pressed a little bit more, she had a four-year-old history of culture-proven herpetic keratitis in this eye, which had been treated topically and then she was put on a couple of years of prophylactic Valtrex, valacyclovir, and she stopped and really never had this occur again. So definitely you want to look at alternative diagnoses such as recurrent herpetic disease. So in this patient, she’s on a steroid, kind of needs that, and this is a classic example of where you’re trying to balance the risk/benefit. Someone asked a question earlier. You want to stop this if it’s epithelial disease, but she’s gonna reject. So we need to balance out what I’m doing potentially treating herpetic recurrence. I got cultures, decreased steroid, put her on oral Valtrex, did not want to put her on topical therapy at this stage, because I wasn’t certain whether this is truly herpetic or not. The appearance is a little bit atypical. However, the fact that she had such a large epithelial defect after being fully healed for the first six weeks, was a bit atypical as well. So these are classic conundrums. Sometimes we don’t have a good answer and need to give it our best shot. Next slide. We’ll try to wrap this up here. 68-year-old male with history of DSEK seven months ago, tapered off prednisolone one week prior to presentation. And once again, you can see that there’s some light sensitivity and slight blurriness of vision. If you look at the slit beam, you’ll see deposits on the cornea, what we call keratic precipitates. You can get graft rejection in DSEK and DMEK, the endothelial transplants. Usually they occur in this classic diffuse keratic precipitates. You don’t see the classic line that you do in penetrating keratoplasty patients. It’s important to be aware of this. You might miss it if you’re not looking carefully, and you want to treat this patient with courses of steroids, and these patients do need years long if not lifelong steroid management. And finally, if we can go to the next slide, this is our last poll question. The following image depicts white spots in the superficial cornea three months after penetrating keratoplasty. It does not stain with fluorescein or rose bengal. What’s your plan? Nothing, these are benign degenerated epithelial cells, scrape for culture and begin broad spectrum antibiotic drops, return to the operating room for suture replacement, or perform confocal microscopy for acanthamoeba evaluation. And this is great. I like this. We have a mixed bag of answers here. These are classic white dots. These are benign degenerated cells. So you do nothing. These are caused by divots in the cornea, near sutures, oftentimes they resolve after those irregularities in the corneal surface improve. Which often occurs after suture removal. But you don’t have to do anything. So once again, the cornea is a wonderful organ, I think. Wonderful part of the eye to focus on. Because a lot of what we do is just really visual, if you’ve seen it enough, you know what it is, and you can save yourself a whole host of workup, when you know what you’re dealing with in advance. So thank you, and hopefully we can answer any questions, or maybe wrap it up, if we’re running out of time. >> So it looks like that’s all the questions. Maybe we’ll wait a minute or two. DR LEHMANN: I’ll answer that one. From an anonymous attendee. How long for hydrops before using intracameral SF6? I’ve seen data where people do it immediately. But you’ve got to take a phakic patient to the ORI. In my opinion, it fixes itself most of the time. So I wouldn’t do anything in that situation. However, if they weren’t better after a few weeks, I would consider it. Rahul, have you done that? DR PANDIT: I think your answer is absolutely correct. And as I’m reading this and seeing we have limited time… Let me see if I can get this next one too. I know this doctor asked this earlier. How to manage persistent corneal epithelial defects. I was supposed to try to answer that. If I can real quickly, this is a complex answer. And there’s no one way to do it. We have a lot of treatment options for persistent corneal epithelial defect. After treating the corneal ulcer, persistent epithelial defect, we were about to do advanced therapy such as amniotic membrane, but I decided to go old-fashioned and put a superior punctal plug, collagen dissolvable punctal plug, and he healed after four days. So sometimes you have to remove drops that are irritating with any preservatives, provide moisture by plugging the surface, consider bandage contact lenses, amniotic membrane, which can be done in the office, freeze-dried or fresh frozen, and in other cases, tarsorrhaphy and what not. But we can use classic drops that we use for treating persistent dry eye and what-not. We can use autologous serum, and now we have nerve growth factor as well that’s available to treat these patients as well. DR LEHMANN: I have to run to clinic. Which I’m sure you do, Dr. Pandit. So I’m gonna leave. There’s still some questions that we can type the answers to. I’ll do that, as many as I can here. Unless you want to take any of them — I can log out and you can answer them, Rahul? Do you have time? What do you think? DR PANDIT: Well, fortunately they allowed me to delay my patients for half an hour, so I have another ten minutes. I can stay on. Or if we need to wrap it up… DR LEHMANN: I think you can do it. Answer them online. I’ve got to log out and drive to my clinic. But I want to thank everybody for their attention. Thanks, Rahul. Turn it over to you. DR PANDIT: Thanks, James. I’ve got to say, having a partner who can help you out, like Dr. Lehmann, is always helpful for patients. Having people to kind of give you a second perspective. Because sometimes it can be confusing, especially in the arena of cornea. So I think that’s one of the key takeaways from this talk, if nothing else. Corneal conjunctivalization, sorry, there was another question. I’ll answer this one first. Corneal conjunctivalization is complex. You have to look at the cause of it. What is causing the conjunctiva to develop blood vessels? It can be neovascularization from a loose suture, if there’s a pterygium, that’s a completely different cause, so you want to take on the cause and address it. There’s not one blanket answer for that. But in some cases what’s been helpful in patients who have had recurrent pterygial growths or scarring from keratitis in the past, one thing we’ve used is injectable Avastin or bevacizumab, anti-VEGF. We also have topical versions. They’re expensive when they’re formulated here in the US. They have to go to special compounding pharmacies. But these can be helpful for patients as well. Oral versus IV voriconazole in severe fungal keratitis. I tried to answer this earlier in a typed question. There’s no proven benefit to systemic antifungal therapy. This is a great study that came out of India in some of the SCUT trials. Topical is definitely the way to go, but I have resorted to oral, in cases where I’m concerned perhaps that we’re just not getting what we need to, or perhaps I’m concerned about endophthalmitis, which usually if there’s endophthalmitis, fungal, it’s gonna progress pretty rapidly. You’re gonna need something more than just oral therapy. So sometimes I think we’re treating ourselves when we do that. But the other reason we might consider it is if we’re concerned about actually the patient getting the doses of medications in their eye, at the frequency that we need to. We all know that the topical formulated antifungals or even the over-the-counter available ones such as nystatin are very difficult to use. They really cake up on the eye and cause a lot of crusting and irritation. Stem cell therapy on corneal dystrophy. There’s a lot of stem cell options. I don’t specialize in that. But I know that there are currently studies looking at cultured stem cells. Really what we have now is stem cell transplant, autologous, and I know SightLife has a great program on that. So I’ll defer to them on future follow-up for that. Steroids, postkeratoplasty patients. If Dr. Lehmann were here, he would say lifelong. Generally I would agree with that for all penetrating keratoplasty patients. And quite honestly, I have no problems recommending that for my endothelial keratoplasty patients. I will say this, though. For many of my endothelial keratoplasty patients, I do give them the option of getting off their one time a day topical steroid after three years. If they feel really encumbered by it for some reason. Which is hard for me to understand. It’s only one drop a day. But some patients really don’t want to continue that. For post penetrating keratoplasty, I do not discontinue it. Having said that, I’ve had patients I’ve picked up over the years from my senior partner who has retired from surgery, they may have had a transplant 30 years ago, and they’re doing fine off their steroid eye drop for the past 20 years. Obviously I’m not gonna put them on a steroid drop at that stage. IAC drops? I’m not certain what IAC stands for. If Wassil SOAL could clarify, I would be happy to try to answer. Bandage contact lenses or soft scleral lenses in some of the corneal degenerations to increase drug delivery. We don’t necessarily use bandage contact lenses unless there’s a reason to. Such as persistent epitheliopathy. We don’t have soaked contact lenses available. Sometimes people do that in their own hospital setting. A contact lens soaked into an antibiotic solution. I know that there may be products available on the market, in the future, for that. But quite honestly, we find that the bandage contact lens has its pros and cons, as does any device put on the eye. And I have several patients over the years with a bandage contact lens who have shown significant keratitis response to the contact lens. Whereas obviously many others respond very well to it. So I think any time you… Put a device in the eye, you do have to be cautious. Prokera or fresh/frozen amniotic membrane, we have patients who do very well with the hard plastic ring in the eye, and it really helps with their epitheliopathy, but I have several patients over the years who have literally come in later that day or the next day and demanded I take it out because it was so uncomfortable they just couldn’t tolerate it. Mooren’s ulcer, peripheral ulcerative disease — I think we have to defer that in the interests of time. I’m trying to see if there’s anything we can answer from our talk here that we didn’t thoroughly cover. Somebody asked a good question about oral or IV methylprednisolone for graft rejection. I do in certain cases, where I’m concerned about needing to get a very high dose or severe rejection, or in a threepeat, third or fourth graft in a patient, certainly. In terms of regrafting, do I start them on steroids or oral therapy? Certainly we can consider that. Usually if I’m gonna consider systemic immunosuppression, I’ll incorporate my colleagues in the rheumatology department to help manage that, because obviously you have to be concerned about blood draws and systemic side effects, which they’re best equipped to follow. Probably have a couple more minutes. Let me see if I can get anything here real quick. Active corneal ulcer with corneal perforation. Those are the easiest because you know you’ve got to take them to the operating room and cut the whole thing out. You can get rid of the disease often in one step with surgery, such as penetrating keratoplasty in those patients. You also get nice tissue diagnosis where the pathologist can look on the slide, and of course, you can get cultures and really see how deep the infection is, whether there’s active or other issues such as fungus and what-not. Dual layer. Yeah. Dr. Herman came up with Dua Layer — if you look at it carefully, it’s helpful in certain corneal transplant procedures, where they’re trying to eliminate PDEK. That’s really where the advantage of identifying that is. Practically speaking, it doesn’t change anything in terms of disease management. Maybe one more question if I can get to… Corneal abrasion for a 3-year-old. Similar to any other treatment, except they obviously aren’t going to accept the treatment you’re gonna do. So in those cases you might have to go back to old-fashioned patching. Recurrent corneal erosion. We covered that a little bit. But you can do of course just conservative management of the ocular surface. Doing dry eye management. As well as treatments for recurrent corneal erosion similar to map-dot-fingerprint or epithelial basement dystrophy. If they’re outside of the visual axis you can do stromal micropuncture in the clinic, you take a 30 gauge needle, bend the tip, and puncture 40% depth in the cornea. Up to 40%. Usually a little bit less, 20% to 40%, and get the epithelial basement membrane to scar down. Of course, superficial keratectomy is helpful as well. A lot of people use alternative therapies in advance of those, and those are fine too, such as amniotic membranes, autologous serum, artificial tears, punctal plugging. Those are great. If those fail, go on to the next therapy. Perhaps we should leave it at that, because we’re gonna be out of time here. These are some great questions, but perhaps you can submit these and we can try to answer them later. DR MAZHAR: I’ve made a note of the questions. I can send them to you and have you follow up with the individuals who have asked them. I want to be mindful of your time. So thank you so much. >> Great. Thank you, Dr. Pandit. DR PANDIT: Thank you all. DR MAZHAR: Thank you, everyone, and take care.

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July 9, 2020

Last Updated: October 31, 2022

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