Lecture: Glaucoma following Congenital Cataract Surgery

Pseudophakic glaucoma can be a potential disaster following cataract surgery in children. Learn what can predispose to having it, how to detect it, how to avoid it and what to do about it if it happens from our expert of the hour, Dr Sirisha Senthil of LVPrasad Eye Institute, India. Powered by Nigerian Pediatric Ophthalmologists and Cybersight.

Lecturer: Dr. Sirisha Senthil, L V Prasad Eye Institute, Hyderabad
Panelist: Adedayo Adio FWACS, Consultant Pediatric Ophthalmologist
University of Port Harcourt teaching hospital, Nigeria.
Chairperson, Nigerian Pediatric Ophthalmology and Strabismus Society (NIPOSS)



DR ADIO: Hello, everyone. My name is Adedayo Adio. I’m a consultant pediatric ophthalmologist working in Nigeria, and I’m currently the Chairperson of the Nigerian Pediatric Ophthalmology Society. And Strabismus Society. So what is it? This is the society of all pediatric ophthalmologists in Nigeria, committed to ensuring the overall eye health of the Nigerian child. I would really like to appreciate Cybersight for this collaboration. It was born out of need for continuous medical education for all our members, spread all over the country in Nigeria. And why not share with everyone? So we have registrants all over the world. We have Australia, French Guyana, and so on and so forth. And we hope to make this as regular as possible. For those of you who may not exactly know where Nigeria is, I would like to just say the following. It’s the world’s second largest and second most populous continent, after Asia, and there are 1.2 billion people spread over 64 countries, one of which is Nigeria, right there. It’s in the West of Africa. It has 36 states. The capital is Abuja, and for the record, we have over 90 million children under the age of 18 years, people in Nigeria under 18 years. So in Nigeria, we have just 37 pediatric ophthalmologists, which is just less than 10% of the entire number of ophthalmologists working in the country. And they’re all spread into 21 centers, as shown there on the map. So why this topic, pseudophakic glaucoma? In developing countries, pediatric cataracts are the most common cause of blindness in children. And it can potentially mar the good visual outcome that the patient already had. Most times, there’s no pain, no redness, but it silently causes blindness. And so as one of our programs to talk about glaucoma, it’s good for us to have an educational topic on this, and of course it’s very important in developing countries, where equipment to properly treat cataracts and glaucoma is not widely available. We find that there are very few studies specifically examining this in children in Nigeria. The study was done about 15 years ago, by Ologunsua and Dr. Alhassan and Rabiu, and it showed that 2.8% of those who had cataract extraction, intraocular lens placed in the posterior chamber, developed some glaucoma. Another study, carried out around the same period, by Arani et al., showed that prevalence varies between 3 and even can go up to 41%. And the infant aphakia treatment study showed a prevalence of 20% of pseudophakic glaucoma in those that were followed up for five years. Quick audits of centers — 21 centers. 7 of them were able to get a response. We find that there was an average of 420 surgeries going on per center, in a period of 18 hours, and about three to one the option was to place an intraocular lens in the patient. And finally, out of that number, 16 of them, even at 0.4% prevalence, pseudophakic glaucoma was there. So we find that it’s not up to 41%, but you don’t want to wait until you have a big problem on your hands, so we’d like to talk about it today. So it seems that we have to keep checking for it, after doing surgery. We should never assume that it can’t happen. So today we’re going to be looking at: Why does this happen in these patients? Why does it not happen in some other patients? How do we diagnose it? How do we recognize it? Then how do we treat? And most important, how do we prevent it? And so no other person than Dr. Sirisha Senthil will be talking to us this morning. She’s a teacher par excellence, a great surgeon, she has great outcomes, she’s very approachable, and she will do great justice to this subject matter. So start writing down your questions. Send them, listen, and learn in the next few minutes. Thank you very much.

DR SENTHIL: Yeah. With the audience permission, I think I would like to cover both aphakic and pseudophakic glaucoma. So I will come to the reason why I would like to do that. So I would like to go through this presentation by going through the definition of what the pseudophakic glaucoma and aphakic glaucoma mean, how common are they, what are the mechanisms of glaucoma, who are at risk of developing this disease, how do you diagnose the disease, how do you treat, and how do we follow up this patient and summarize all of that? Glaucoma in aphakia and pseudophakia is aptly called as the disease of glaucoma in an eye that is either aphakic or pseudophakic. But one should not use the terminology of aphakic glaucoma or pseudophakic glaucoma, because it’s not the pseudophakia that’s causing the glaucoma and not the aphakia that is causing the glaucoma, but there are multiple mechanisms that are there. So we shouldn’t use the term aphakic or pseudophakic glaucoma, but we would try and call them as glaucomas associated with aphakia or pseudophakia, because of the mechanisms that are involved in the disease.

>> According to the latest Childhood Glaucoma Research Network classification, glaucoma that develops after a cataract or clear lens extraction surgery is classified as glaucoma following cataract surgery. All cataract types are included. Glaucoma that exists prior to cataract removal is given a different classification. Okay.

DR SENTHIL: So this is a slide that actually shows you the latest Congenital Glaucoma Research Network classification, where, unlike in the earlier days, where congenital glaucoma or the childhood glaucoma was very vastly divided into multiple subdivisions, so it is very difficult to actually even talk about the prevalence of the disease, or leave alone the management of part of it. So nowadays, with the latest classification that is coming, which has made things very easy, where all the types of cataract, be it congenital, be it acquired, be it developmental or secondary to any disease, so all types of cataract actually are categorized into glaucoma associated with cataract surgery in children. So that has made things very clear for us to understand what are the various types of glaucoma, what are the various mechanisms, so that it will help us to even try and give our treatment options according to the mechanisms of glaucoma. So how common is this disease? Prevalence of glaucoma in these eyes who have undergone a pediatric cataract surgery could vary from 0 to 100. So whenever you talk about 0 to 100, then you can understand the range is huge. So if you follow up these children long enough, several of these people develop glaucoma, and this is actually — 100% is something that is based on an article that was published by David Walton, where they have followed up the children who were operated for congenital cataract for over 33 years, and over that time, they found that every single person who underwent a pediatric cataract surgery developed a glaucoma. Of course, in the earlier days, several of them used to have a different mechanism of glaucoma, because of aphakia. But even with the modern advance of the vitrectomy procedures and with the use of intraocular lenses, the pediatric glaucoma related to congenital cataract surgery has not come down to a great extent. So there are various definitions of glaucoma that are used. Surgical techniques are variable. Age at diagnosis is very different. Type of surgery, as well as the duration of follow-up, very variable across these studies. So like I said, starting from the couching to the needling and aspiration, lens aspiration, followed by a vitrectomy procedure in the late 1970s to the late 1980s, where a very well performed phacoemulsification or a lens aspiration with a PCIOL implantation is a technique that is followed. We need to look at glaucoma before the automatic vitrectomy lensectomy, where the prevalence of glaucoma was quite high. But in some of the studies, the prevalence was very low. Was it because the disease was low, or was it because it was not detected? That is also a huge issue. This is glaucoma after automatic vitrectomy. If you look at this, after automatic vitrectomy, and even with the advent of intraocular lens implantation, the prevalence of glaucoma — the incidence of glaucoma has not come down to a great extent. So this is the study I was quoting about. Chen and Walton. In their publication, they have shown that at one year, 37% of the eyes develop glaucoma. 75% of them develop by 6 years of follow-up, and by 33 years of follow-up, close to 100% of them develop glaucoma. It’s a very interesting article, where the natural history of development of ocular hypertension and glaucoma after pediatric cataract surgery was studied by Egbert et al., where they showed us that over a follow-up period of 7.5 years, close to 7.5 years, close to 23% of them developed ocular hypertension. And ocular hypertension to glaucoma. And close to 24% of them, an equal number of them, developed ocular hypertension from normalcy. That means — there are various stages. So initially the intraocular pressures are normal, then they have just an elevated intraocular pressure. There is no disc damage. There are no other changes that you really perceive. Over a period of time, the people with ocular hypertension, close to 1/4 of them actually develop a glaucoma. So any elevation in intraocular pressure that you see in these children, be it pseudophakic or aphakic, should not be left untreated. They need to be monitored very, very closely. This is a recent publication from our institute, where we looked at — in fact, until recently, until, I would say, early in 2019, we didn’t have a profile of childhood glaucoma from any center. That means if you look at all children with glaucoma, and then try to see what are the different types of glaucomas that presented to a tertiary eyecare center, we didn’t have a number at all. So this is what was looked at, over almost about 15 months’ time period. This was prospectively collected. And as expected, the highest number of glaucomas were primary childhood glaucoma. So when we put together the primary childhood glaucoma, as well as the infant glaucoma, that was the highest. When we looked at secondary glaucomas, like with the CGRN classification, we looked at glaucoma following cataract surgery, as well as glaucoma following acquired diseases. So if you want to look at a secondary glaucoma, so the second commonest was steroid-induced glaucoma and traumatic glaucoma. And following that was glaucoma following cataract surgery. So this is a prospective study done in one center, in one year. So you can understand the magnitude of the problem, and if you look at pediatric ophthalmology-related surgeries, the commonest surgery that is done in children is a pediatric cataract surgery. So if you put that together, the number of people with glaucoma following a pediatric cataract surgery are going to be quite immense. And we also have to understand: Many of the children, especially in the developing countries, they also have glaucoma associated with other syndromic abnormalities, as well as other ocular anomalies, who also have a congenital cataract. So if you have a disease of a cataract, associated with other congenital ocular problems, then the chances of them developing glaucoma are going to be very, very high, and several of these eyes in fact would remain aphakic, because of the complexity of the eyes, as well as the complexity of the problem that they have. Broadly, we can classify these glaucomas as closed angles as well as open angles. So like in adults, for you to diagnose — so if you look at treatment of glaucoma, essentially it is going to be medical, and if medical does not work, medications don’t work, we go in for a surgery. But what we need to understand is: Like in adults, if you have to treat somebody in a certain way, you need to understand why the glaucoma has developed. For you to know why the glaucoma has developed, you need to know the pathophysiology or the mechanism of glaucoma. So you need to look at several other factors. But the most important one is to go and look at the angle. So that means gonioscopy becomes a very integral part of examining these children. So closed-angle glaucoma can be of multiple mechanisms, again. Pupillary block used to be a very common problem, as far as aphakic glaucoma was concerned, but looking at pseudophakic glaucoma, it was not very common. But having said that, even in eyes with pseudophakic glaucoma, incomplete lens removal — that means residual cortical matter or residual lens material that is left behind — or severe inflammation in the postoperative period, either because of inadequate steroids or if the patient has not used the medications appropriately, or abruptly stopped the medication, or presence of a complicated cataract surgery, even in the presence of a pseudophakic eye, presence of vitreous in the anterior chamber, or inflammation that was not detected, as well as if these children also are going to have a recurrent inflammation over a period of time, they can also develop a chronic angle closure. Apart from these other mechanisms that could be associated, would be retained viscoelastic. If you have a lump of viscoelastic material that is left behind, either behind the iris or in the anterior chamber. That also can produce a lot of inflammation. So ultimately, it all boils down to: Either it is a pupillary block or because of excessive inflammation that is present in these eyes. Open-angle glaucoma also develops, but that is usually at a later point in time. So usually at the earlier part of the postoperative period, you have certain mechanisms. At a later time period, you have a certain mechanism. So we’ll come to that in the subsequent slides, but the open-angle mechanisms are also many. Two of the reasons why an open-angle glaucoma develops in these eyes, according to what the theories tell, is the mechanical theory, where especially in aphakic eyes, or even those eyes where you remove the lens, there is removal of the lens because of which the zonules are lax, and there is release of traction on the trabecular meshwork, because the zonules are attached to the scleral spur, and there is a release of traction on the scleral spur, and hence the trabecular meshwork collapses. And possibly because of which there is closure of the drainage through the trabecular meshwork, as such. Also because of retained lens material. So that is one of the reasons why you can have glaucoma. And the other reason: This need not, again, necessarily be in an aphakic eye, but even in a pseudophakic eye, this holds true, especially if you have retained lens material. If you have inflammatory material, vitreous in the anterior chamber, prolonged use of steroids. All of these also can cause clogging of the trabecular meshwork, because of which we can develop an open-angle glaucoma. So the chemical theory that is proposed is — this is again more so common with aphakic eyes, but even in pseudophakic eyes, even if you leave behind a few lens epithelial cells in the periphery, or because we know that children — lens epithelial cells in kids is very, very active, so even the residual cells from the anterior capsule, the remnant of the anterior capsule, also can grow. And all of these cells can release chemical mediators which can alter the structure and function of the trabecular meshwork. That also can lead to an open-angle type of glaucoma. So this is a very, very important slide. What is the time interval at the development of glaucoma, following cataract surgery? So this can develop as early as day one. In fact, this is not unusual for us. When a child you see in the day one — so on the table, the cornea was clear, everything was fantastic, but day one, postoperative, and you see the child is not allowing you to examine. The baby is crying. And even if you forcefully examine the child, or you put the baby under sedation or under anesthesia, and when you examine, you realize that the cornea is completely hazy, and you know the first thing that comes to your mind when the cornea is hazy is the pressures are increased. So that could be again because of retained viscoelastic in the anterior chamber, overfill of anterior chamber, and of course the response that the pupillary block that they can develop — because over 24 hours, they can develop a thin membrane over the pupillary area. Even in pseudophakic eyes, one can develop a pupillary block. So if you have a very high intraocular pressure in the early postoperative period, angle closure glaucoma, especially the pupillary block, is the commonest cause. Over a time period, and steroid-induced is one more cause that can develop in the early postoperative period. Usually by about the third to fourth week. So steroid responsiveness in children is biphasic. That means the kids are in populations — generally in children, as well as in very old people. There is a very high steroid responsiveness rate. And children, kids, are highly steroid responsive. I’m not sure how it is in Nigeria, but as far as India is concerned, we see steroid responsiveness to be a very big problem. Especially Adio would remember — when you operate one eye, and when the baby is ready to undergo surgery for the other eye, you would do an E and M, and we want to do the suture removal — you realize that the first operated eye has pressures that have shot up now. So that is not at all unusual for us to see that. So tapering of the steroids and switching them to a low dose steroid is an issue, because inflammation is a major problem, so you would want to give them steroids. If you taper these steroids in a shorter time period, that would allow the inflammation to flare up again. So this is a double edged sword. So one has to be very, very careful in using the steroid medications. While it is useful, it can also be harmful in certain patients. So open-angle glaucoma that can develop over many, many years could be because of the changes that happen in the trabecular meshwork, and what we understand from this is that if you follow up these kids long enough, surely whatever is the mechanism that they have — at some point in time, during their lifetime, they will definitely have an elevated intraocular pressure and a disc damage. So coming to the risk factors, who are at risk? So the question that Adio had put together, where — who are at risk? So there are several of these children who undergo cataract surgery. Do all of them develop glaucoma? Do we need to be looking at those people at risk and possibly trying to evaluate them more often and trying to see them more often? So who are at risk? If you look at the very beautiful graph that shows a development of glaucoma following pediatric cataract surgery, and many of us are aware that the younger the child is, when you do a cataract surgery, less than 9 months of age, the chance of developing glaucoma is quite high. So there was a 37% chance of developing glaucoma following a cataract surgery in children less than 9 months of age, as opposed to children who are older than 9 months of age, where the percentage was only 6%. So you can understand the younger they are, especially if they have a bilateral cataract, you definitely would want unilateral cataract — you would definitely do it. Bilateral cataract also. Because you want to start having their visual stimulation earlier. You would like to operate them much earlier. But if they’re very young, and the other risk factor being a very small corneal diameter, like I was discussing, multiple other associated abnormalities in the cornea, preexisting ocular conditions, as well as systemic abnormalities, and also the type of cataract. So certain types of cataract are also at higher risk of developing glaucoma, like the lamellar type of cataract, the nuclear type of cataract, so these are some conditions, a total cataract, in certain conditions, and also certain comorbidities. For example, congenital rubella syndrome. So you know that these children have a congenital cataract. At the same time, they also can have associated glaucoma, preexisting, and these eyes, because of the smaller corneal diameter that they have, and the increased intraocular inflammation, are also more prone for the development of secondary glaucoma. Second interventions are a major problem. So when you see pseudophakic glaucoma or glaucoma in pseudophakia, one also has to remember secondary intraocular lens implantation in children is a major risk for development of elevated intraocular pressure in the postoperative period. So if their trabecular meshwork is kind of compromised, but they’ve compensated for now, their intraocular pressures are okay, always try and do a gonioscopy. If you see a significant amount of angle closure in these eyes, and their intraocular pressure is kind of hovering in the 20s, one needs to be really, really careful before doing a secondary intraocular lens implantation, because they have a very, very high chance of developing elevated intraocular pressure. In fact, some of the intractable glaucomas related to pediatric cataract surgery that we treat are actually following a secondary IOL implantation, and not after a primary IOL implantation. I think that’s something that we need to remember. So whenever they undergo a second procedure, be it a membranectomy, be it a secondary intraocular lens implantation, or any other intervention, for that matter, some of them have slipped intraocular lenses — especially those that have a glued intraocular lens, and things like that. So any intervention, second or third time, they would have a higher risk of developing glaucoma. Retained lens material — of course, this picture is a representative photograph. But retained lens material, even if it means a small fragment of lens material that is there, can lead to severe inflammation and prolonged use of steroids. So all of these can tend to increase the chances of developing a glaucoma. Corneal diameter. This is, again, a very, very important risk factor. So smaller corneal diameters we know have abnormal anterior segments, are associated with eyes with abnormal anterior segments, and these eyes are more prone to developing glaucoma. So any corneal diameter that is less than 10 millimeters has a 32% chance of developing glaucoma, versus somebody whose corneal diameter is more. So this is something that all of us know. So this is an article which Adio had shown as well. So this is a very interesting article, which has asked a question: Is implanting an intraocular lens a preventative strategy for the development of glaucoma? So this is a very interesting paper. It was actually a review article, where they looked at multiple publications, where glaucoma in aphakia and pseudophakia was there, and they had over 1,000 eyes. And a very interesting Kaplan-Meier survival analysis. If you see here, this is — the dotted line here is the eyes with an intraocular lens implanted, and these are the aphakic. Aphakic eyes, over a period of time, as the number of years went by, their survival — this is glaucoma-free survival. So glaucoma-free survival kept going down in aphakic eyes, whereas in those with pseudophakia, it was a straight line. That means even over a period — so this was a 12-year follow-up. Even after 12 years, they did not find a single eye with glaucoma. So now you know why I did not want to choose just that topic, because you hardly have any glaucoma. That is what people say. But that is not true. Because each of us who is involved in caring for these children, we know that that is absolutely not true. So it’s possible that in the initial period of time — so this was published in 2000. In the initial period of time, the eyes where we chose to do the intraocular lens implantation were those eyes that were out of the risk factors. That means they were eyes with large corneal diameter, they were children who were older, they were children with no other comorbidities, so those children were kind of chosen to do the intraocular lens implantation. And possibly followed up very well. Because of which, the chances of development of glaucoma were less. So once the technique is learned, and nowadays, I think we do intraocular lens implantation to even the high risk children. So we need to understand that as we become more comfortable with doing a procedure with the vitrectomies, as well as doing different types of surgeries, and the kind of complexities that we can handle today, I think we are dealing with a lot of complex patients. And several of these, like I said — these children are growing bigger, and now they’re having a secondary intraocular lens implantation done, so over a period of time, glaucoma with pseudophakia may be, as we go by, in a couple of years — in fact, we are working on that data now. So in a couple of years, we will also come to know about what is the difference between these two, and what could be the risk factors in pseudophakia, versus what could be the risk factors in aphakia. In the same cohort of patients. But currently, the risk factors that we spoke about essentially are the same, except for a few where you’re talking about vitreous blocking the pupillary area, and things like that. So acute pupillary block, which in the previtrectomy era and in the aphakic eyes were much more common. But apart from that, I think the rest of the mechanisms and complications would still hold good today. So once we know who are at risk, and whenever these children come — in fact, as pediatric ophthalmologists, once you do the cataract surgery, I think it is mandatory that they need to be followed for the rest of their life. So wherever they go, I think this is something that needs to be told to them. Because once everything was well, they may not even come back. They may come back to you 10 years later, 20 years later, but by then, it’s already too late. In fact, it’s not uncommon for us now to see children who were operated 15, 20 years ago. They’re adults now, they come back to us, with some decrease in vision, or some of them are coming for refractive correction. So when you go and examine them, in fact, there was recently a boy who was 28, 29 years old, who was completely blind in one eye, and he was actually functioning with the other eye, which also had a very advanced glaucoma, but he was not aware of that. So what we need to do is: We have to educate the parents that these children are at risk of developing glaucoma. So they need to be followed up routinely. So what do we do to evaluate them? Just like you do the vision, the refraction, every visit that they come, and based on the myopic shift and the refractive error, sometimes especially if they’re young children, we also do the axial length. And central corneal thickness, of course. It helps you, but I will come to that a little later, as to how we can use the CCT in the diagnosis and management. That apart, I think intraocular pressure measurement is a very, very important part of examination of these children. So if you ask me what is the best tool to use, to do the IOP evaluation, you can check the intraocular pressure with any instrument that’s available to you. That will be the first thing that I can tell you. That means if you have a Perkins, if you have a Goldmann applanation tonometer, if you have an Icare, if you have TonoPen, whatever is the instrument that you have, you can check the intraocular pressure. If they are very young children, they wouldn’t allow you to use the Perkins or Goldmann applanation tonometer. One of the instruments that we are routinely using now is the Icare tonometer. A recent study that we had done in our institute actually is accepted for publication in the month of March, in Ophthalmology Journal. What we showed was: If the intraocular pressure measurement with Icare or Icare Pro tonometer in the office — if it is less than 19 millimeters of mercury or less, it correlated very well with Perkins tonometer or Goldmann applanation tonometer. Whatever you wanted to. So applanation, as well as the intraocular pressure measurement by Icare, were very good and correlated very well, if it was 19 or less. That means if your recording in the office is 19 millimeters or less, anyway you wouldn’t have to worry about them, and you know that they are fine, so you don’t have to subject them to anesthesia again and again. But if the intraocular pressure measurement is beyond 19, I think one needs to be careful. We cannot start treatment based on that IOP reading. We definitely have to recheck the intraocular pressures by examining under anesthesia or under sedation or whatever is the best technique that is available to you. Disc changes, of course — we need to document them, if it is possible. You can draw, take a disc photograph, or if you have a RetCam, please do it, but disc evaluation is very, very important. And in children, because they may not be able to do the visual fields appropriately, and of course the OCT and the modern techniques that you have — they do not have a normative database of children, so you cannot evaluate them — essentially it goes by the objective evaluation, because all of these factors have to be taken together into account, before we diagnose them as having glaucoma. Corneal examination. Unlike in other children with glaucoma, where you have a childhood glaucoma, it’s very easy to diagnose, because of the corneal edema, the enlarged corneal diameter, presence of Haab striae, and things like that, but in children with postcongenital cataract surgery, be it aphakic or pseudophakic glaucoma, generally the eyes are quiet. They do not have so much of corneal changes that you notice. If at all they have a change, a very, very high intraocular pressure — this was in a child’s eye, whose intraocular pressure was beyond 40 millimeters of mercury. So if it is like that, you can see a diffuse corneal haze. Other than that, you don’t really see any other findings of Haab striae and things like that. So presence of a corneal haze, and especially the difference in the color between the two eyes, is something that gives you a clue. So that is a very important clue. Of course, retinoscopy, to see if there is increase in myopia, as well as presence or absence of irregular astigmatism, if there is Haab striae, is something that we need to look at. And Perkins tonometer, like I said, Perkins can be used, but Icare or TonoPen — whatever you have you can use. So if you ask me what is the IOP cutoff, if you are examining the baby under anesthesia, you know that especially the inhalation anesthetics that we use can bring down the intraocular pressure by 4 to 5 millimeters of mercury. This is an approximate estimation. So under anesthesia, you wouldn’t take a cutoff of 21, 22, 23. So under anesthesia, I would take a cutoff of up to 16 millimeters of mercury, because of the decrease in the intraocular pressure, because of the inhalational anesthetics. On the other hand, if we’re examining the children in the clinic, I think because of the increase in the central corneal thickness that happens in these children postcongenital cataract surgery, both in pseudophakic and aphakic eyes, usually we take a cutoff of up to 24 to 26 millimeters of mercury. But do not treat children based on one intraocular pressure reading. Always repeat the intraocular pressure. The child may be uncooperative, for whatever reason. You recorded the pressures high on that day, but you would always call the baby back another day, early, and then reexamine the intraocular pressures to see if what you are recording was persistently elevated, or was it just that one off reading that you had, because the child was not cooperative? Like I mentioned, mechanism of glaucoma is extremely important. Gonioscopy is very, very important. So we can use a 4 mirror gonio lens in the clinic. In fact, even under anesthesia — we stopped using the Koeppe lens. We used the 4 mirror gonio lens even for examination under anesthesia, because it’s very, very easy to use. You don’t require a coupling fluid. You will be able to examine all the four quadrants very easily, to understand what’s happening in the angle. So to know whether it is an open-angle, angle closure, or is there a foreign body, is there the haptic of the intraocular lens, which is poking through the iris, and coming and irritating, or is there retained lens material there in the angle? So whatever are the problems that could be associated with these eyes and with these angles? We will be able to make out once we do a gonioscopy. Slit lamp examination, whether it is the handheld or routine slit lamp examination, is extremely important to evaluate the cornea. Optic nerve head assessment is, again, very, very important. So every visit — so if you say that every visit I will do a vision refraction intraocular pressure, of course gonioscopy you wouldn’t want to repeat every time, but every time you see elevated intraocular pressure, you would want to do a gonioscopy. But apart from that, a disc evaluation. So if you make this a point, and you make a chart, and say: Every visit the baby comes, this is what we will do — then I think you will definitely not be missing the elevated intraocular pressures or glaucoma in these children. So this is a commonly asked question: How do you use the CCT measurements in children? How do you understand whether the IOP that you measured is appropriate or not? And how would you change your treatment based on the CCT? So we need to be aware that central corneal thickness measurement, like for adults, as far as the Goldmann applanation tonometer is concerned, when Goldmann designed the tonometer, he assumed that everybody’s corneal thickness was a corneal thickness of 520 microns. So the problem is not about the normal CCT or an elevated — or a thin cornea or a thick cornea. It’s about how the tonometer was designed. So when somebody’s corneal thickness was 520 microns, the Goldmann applanation tonometer will have the least error. If the corneal thickness was on the lesser side, that is, less than 520, or less than 500, if you want to put it as thin corneas, you will be underestimating the intraocular pressure. If the corneal thickness is more than 550, you will be overestimating the intraocular pressure. So this is an approximate guide. So in children, following a congenital cataract surgery, their corneal thickness increases. Why does this happen? It happens because, if you are operating on somebody at a very, very early age, and they are exposed to the material used during surgery, exposed to the lens material, exposed to the chemical mediators inside the eye, whether it is vitreous-related or inflammatory marker-related, there is an altered corneal development. There is also endothelial damage, because of the procedure itself. Especially if they have an elevated intraocular pressure, they have an ongoing damage to the endothelium. And of course, as time goes by, because of these chemical mediators, there is abnormal corneal maturation. So this is a table showing the central corneal thickness of pediatric glaucoma eyes, as well as the control eyes. In children with aphakia, the corneal thickness is quite high. So this is a table that is showing you in various studies where glaucoma in aphakia and pseudophakia compared, and they looked at the central corneal thickness in these two cohorts. You saw the corneal thickness in aphakia was definitely more than in pseudophakia. Having said that, even in pseudophakic eyes, the corneal thickness is definitely much more compared to the controls. Another major problem that we have, as far as the glaucoma in these eyes are concerned is, like we discussed, in contrast to the congenital glaucoma patients, several ever these children are asymptomatic. They will be perfectly fine, going about doing their own work, and they never come and complain, and the majority of the children go very close to the television to watch whatever they are seeing, so you’re not sure whether they have — is that normal for a kid? Or do they have a problem with their vision? And hence they have a difficulty? Many of these children are amblyopic, at least in one eye, and if the child has decreased vision right from the beginning, because of other pathology of the macular maturation and things like that — so if they’re seeing less, you wouldn’t know how to estimate whether they’re seeing less because of their already preexisting problem, or they’re seeing less because of a new problem that they’re developing. Intraocular pressure estimation, again, is not something that is done routinely. I think one thing I would like to emphasize is: If anybody who is touching these children and operating — I think they should make it mandatory to be able to evaluate their intraocular pressure and disc as well, at every follow-up that they come. They are difficult to perform, but I guess if you are a pediatric ophthalmologist, managing more complex problems, checking intraocular pressure I don’t think is a very difficult thing to do at all. And like I said, the majority of them have small pupil, they have almost normal-looking corneas, and especially they have a very tiny pupil, non-dilating pupil, then it’s very, very difficult to do a disc evaluation. Sometimes we have some children for whom the pupil is just about 2 or 3 millimeters. It wouldn’t dilate, whatever you want to do. So one of the ways of evaluating the posterior segment in these children, apart from just checking the IOP and vision, is we do a B scan ultrasound. Again, B scan ultrasound — can it give you changes in the optic nerve? Very unlikely. Yes, if it is a very advanced cupping, then anything beyond 0.8 — maybe it will give you the change that you can see on a B scan. But that is not what is used to evaluate glaucoma. But we routinely do that, because these eyes are also prone for development of — because of the ocular enlargement — plus doing surgery at a young age — retinal detachment is, again, a problem that can be there in these kids. So you would want to do — if you can see the fundus, at least do a B scan once in a year. That is a routine that we follow. And of course, like I said, visual fields are very difficult to do. The earliest stage that we do a visual field with somebody who is cooperative — even at 6 years of age, we can do it. But having said that, if they are not able to do it very well, we have a pediatric perimeter that’s coming up, which underway in our institute. But that is really far from use for a child at this point in time. But yes, we do not have a way of estimating their visual field. So once you diagnose, how do you treat? Unlike in the other type of glaucomas that we discuss about, whether it is a primary congenital glaucoma or the other types of glaucomas, where surgery forms a main mode of therapy, the majority of these children actually can be very well treated medically. In fact, in our cohort, when we analyzed our results, 85% of these children with glaucoma in aphakia and pseudophakia — so when I use the term “glaucoma”, I’m also including those with ocular hypertension — so anybody with an elevated intraocular pressure that needed treatment, 85% of them actually — we were able to treat them medically. And only the other 15% required a surgical intervention to control the intraocular pressure. So several of them actually do very well. What is the first drug of choice in children? First drug of choice in children, if there are no other systemic problems, beta blockers and carbonic anhydrase inhibitors are the choice. You can use them as a combination or as a single drug, based on the availability as well as the cost, and if they’re very young children, then carbonic anhydrase inhibitors are the primary choice, followed by beta blockers. Prostaglandin analogs are used sparingly, because we do not know how well they work, and they’re also on the expensive side. So cost apart, the efficacy is not as good as the carbonic anhydrase inhibitors or the beta blockers. Pilocarpine, although it is not a drug that is commonly used, in some children, especially those with open-angle type of a glaucoma — pilocarpine works very well. So pilocarpine is a drug that definitely has its role to play, but in several countries, this drug is not available, so that is an issue. But alpha 2 agonists are something that you would want to avoid, because several of these children, even older children — in fact, there are some of our patients who come back and say that the minute you put the drop, the child goes off to sleep, and then wakes up after 2, 3 hours, and then goes off to school, and then the afternoon dose they skip, because the child again will sleep in the school otherwise. Comes back in the evening, and once dinner is done, they give them the next dose. In about half an hour, the child has gone off to sleep. So it is a drug that can cause a lot of sedation, and because it is lipophilic and can cross the blood-brain barrier, has a very high tendency to cause these side effects, especially in children. So we should try and avoid it. But in extremely difficult situations, where the child is not tolerating any other medication, the intraocular pressures are not coming down, and you’re awaiting a surgery in desperate situations, we do use it in children older than 12 years of age, but less than that, it’s better to avoid using this drug. This is the follow-up chart of the patients in our cohort who had glaucoma following congenital cataract surgery. Of all the types of glaucomas that we have had, whether it was congenital glaucoma, whether it was glaucoma associated with syndromes, glaucoma that is steroid-induced, traumatic, all of them put together, glaucoma following congenital cataract surgery was the most difficult cohort to treat. Their pretreatment intraocular pressure, compared to posttreatment intraocular pressure, the variability was really huge. And the intraocular pressure did not go down as well as it did compared to the other groups. That means they still were in the ranges of 17 to 20, and the intraocular pressure control in the rest of the groups, if you see, were between 8 and 11. So the IOP control does not happen very well. So you never see a 10 IOP, 12 IOP kind of a thing in these children. Either we are inappropriately treating, inadequately treating, or is it because they have a very thick cornea? You are estimating the intraocular pressure slightly on the higher side? That’s difficult to say. But that is one group of patients where it is difficult to treat, and we need to be careful in choosing our medications. Does laser have a role to play? Of course, not the trabeculoplasty, even in those with juvenile glaucomas. We know that laser trabeculoplasty does not have a role to play. But in the presence of a pseudophakic pupillary block or aphakic pupillary block, definitely an Nd:YAG laser would help, if it’s an older child. Otherwise a surgical iridectomy is something that we can do. This is one such eye, where there’s a pseudophakic pupillary block you can see. It’s almost flat. On a cursory examination, diffuse examination, it looks as if everything is okay. But on a slit, you can see that there is a pupillary block. So even in eyes with pseudophakia, you can have a pupillary block. Just following the laser iridotomy, you can see the anterior chamber deepens so well. So why does this happen? This happens either because of the push of the lens iris diaphragm forward, or it is just the intraocular lens that is pushed forward, or the viscoelastic that causes the pupillary block, or you can sometimes have inflammatory membrane, which is covering the pupillary area, which can cause a pupillary block. One of the conditions that I would like to mention in this particular instance is placing. When you are placing an intraocular lens, I’m sure all of you would agree that hydrophobic intraocular lens is not designed to be placed in the sulcus. If there is a situation that arises where your rhexis is not intact, and you are likely to be placing the lens in the sulcus, because you’re not able to place it in the bag, then please do not use a hydrophobic intraocular lens, especially a single piece variety, to be placed in the angle, because that induces a lot of problems. So because of its property, that it is adherent to any tissue that it comes close by, it is basically designed to be very sticky, because it has to stick to the posterior capsule, thereby preventing the posterior capsule opacification, but when you place it in the sulcus, it sticks to the iris, it sticks to any tissue that comes in contact with it, releases a lot of pigment, so they have chronic inflammation for the rest of their life. So that is one thing that we should avoid. If at all, there is a situation that one has to place the lens in the sulcus, use a three piece intraocular lens. That is the safest way to do an intraocular lens implantation. Otherwise, a PMMA lens is good enough, and that can be placed as well. This is a child who is actually a grown-up in his early adulthood now. This is an eye which is aphakic, and actually, the patient had an aphakic pupillary block. The patient came following congenital cataract surgery, had unilateral divergent squint, and came for squint surgery. Underwent squint surgery, and day two, day three following squint surgery, he was found to have very, very high intraocular pressure. They thought it was steroid response, because steroids were given postsquint surgery, and the patient was referred. So this is the importance of gonioscopy that I was talking to you about. Anterior chamber is deep, it’s quiet. It looked like a steroid response. And that is the likely thing that you will think about, because of the recent surgery that the patient underwent. So gonioscopy showed a closed angle, and you can see the peripheral iris — but centrally you see the anterior chamber is quite deep. This is a UBM picture, which is showing you the obvious pupillary block that is there. And this is post-PI. All that was required to do was just do a PI, and his pressures are very well under control. So that is just to retread the fact that pseudophakic or aphakic pupillary block can happen, and gonioscopy is something that is very useful in diagnosing this condition. So if medications don’t help — yeah. One more thing that I must — is use oral acetazolamide. How much can you use? And how long can you use? Is there a role to play for use of oral Diamox? Of course, we can use oral Diamox. Children do tolerate it very well. The maximum dose that we give is up to 20 milligrams per kilogram body weight. But I would, if it is possible, use up to 50 milligrams per kilogram body weight per day. And we can — so one of the side effects that we are worried about, especially if you have to use them chronically, is loss of appetite and loss of weight for children. So please keep a watch on that. But if there is a situation that requires you to, let’s say there is a lot of inflammation, and also the child is a steroid responder — you have to use steroids, continue that, but the intraocular pressure can always be taken care of with the topical plus additional oral acetazolamide, and that can be used. So we use it even for a few months, if we have to, for these children. So they do tolerate it very well. Moving on to surgery, what is the surgery of choice? If the IOP does not go down, like I said, gonioscopy is very, very useful for me. So if you… If there’s a situation where there is 360-degree peripheral anterior synechiae, distorted anterior segment, because of severe inflammation that the child has had, and a pseudophakic eye, I would not even think about doing a trabeculectomy in them. I would straight away want to go and do an implant. Because you know the chance of doing an angle surgery in them is not so good. And doing a trabeculectomy, again, the chances of scarring is going to be very, very high. So they will require a second surgery very soon. So I think one has to choose whatever is ideal for that particular situation, based on the findings that you had. Open angle on gonioscopy, otherwise not much of anterior segment distortion, you would possibly want to go ahead and do a trabeculectomy. If you are able to identify the Schlemm’s canal, we can also do a common trabeculotomy and trabeculectomy. Of course, we can use mitomycin, but you have to be very, very choosy about the dosage, as well as the duration that you use. So we use a 0.04% for 1 to 2 minutes, based on the indication and the stretch in the sclera. If the sclera is extremely stretched and thin, then I wouldn’t use mitomycin. But otherwise, it’s not just the conjunctiva and the Tenon’s thickness, but otherwise you have to worry about the sclera in these children. So the success rates vary anywhere from 50 to 85%. Over a period of time, the success rate also goes down, even with trabeculectomy. But of course, if you’re looking at qualified success, that means post-trabeculectomy, if you need to add medications for control, the majority of them control very well. But there’s a small percentage of patients who may require a second intervention. What is the role of glaucoma drainage devices in these eyes? Like I mentioned, an example where you have to — if the anterior segment, there’s a lot of distortions that you see, plus significant peripheral anterior synechiae, or a failed previous trabeculectomy, you would want to choose implants. What is the type of implant that you will choose? Again, it depends upon… So if you ask me this question, if I have a child who’s coming from a very far-away place, is unlikely to come back for follow-up, then I would prefer to use a valved implant, where I know that the first two weeks or three weeks, if I take care of in the early postoperative period, problems and complications are not going to be many, I would use a valved implant, because the intraocular pressure control is quite instantaneous. And follow-up is also very easy. Having said that, over a period of time — in fact, a recently published report of ours, which I will just show, which shows that over a period of time, because the children have thick Tenon’s, they also develop a very, very thick fibrotic bleb, and that over a period of time, the intraocular pressure starts going down. So the long-term failure is quite high with glaucoma drainage devices which are valved. On the other hand, non-valved implants definitely have a better intraocular pressure control, but the worry is that if they do not come back for follow-up, because they have a long time period that you need to follow them up, ligature opens up, and then they start having problems over the next two or three months. So early postoperative period is not that much of an issue, but the delayed postoperative follow-up is extremely important. So if the child cannot come back for a follow-up for whatever reason, then it becomes very, very tricky. So one has to be very clear about choosing the type of implant, and whatever is best for the child. So this is a picture of a child who actually had congenital galactosemia, and underwent cataract surgery as a baby, was aphakic, underwent secondary intraocular lens implantation when the child was about 13, 14 years old, following which intraocular pressures were absolutely uncontrolled. A lot of distortions in the anterior chamber angle, and so ultimately, we had — and the child had dislocation of their intraocular lens a couple of times. It had to be refixed. The child underwent one implant, it worked for some time, then this picture actually shows you a second implant inferiorly here. Because of the conjunctival elevation, you can also see the dellen that is formed with the staining of the cornea. So sometimes you may resort to use more than one implant, but this is not a routine choice. But under desperate situations, you would want to do that, because you somehow have to bring down the intraocular pressure. So this is the study that we have published last year, where 27% of the children for whom the AGV was implanted, the Ahmed glaucoma valve was implanted, were glaucoma in aphakia and pseudophakia. One thing that I would like to bring to notice is that several of them had this procedure as the primary glaucoma surgery. That means they did not have the trabeculectomy before, none of the other procedures before. Because they were really difficult glaucomas to control, and with a lot of adhesions in the angle. So this is one cohort where they do well if you pick them up early, and if you are treating them appropriately, and implants definitely have a good role to play. And how was the success? We compared the primary glaucomas with the secondary glaucomas. Primary glaucomas, of course, congenital glaucoma, did definitely much better than the secondary glaucoma. But of course, because the numbers were not too big, the statistical significance was not there, the majority of which was almost similar, and the IOP control was maintained at least — this was a four-year follow-up. It was maintained until that time. Number of previous intraocular surgeries was a risk factor for failure of AGV also. So not just trabeculectomy. Even for the implants that we do, this is a valved implant — even for the implants, number of prior intraocular surgeries obviously would be a risk factor for failure as well. Is there any other thing that we can do when all the other procedures fail? Or in certain conditions, let’s say the child is not fit for general anesthesia, or there is a situation where you cannot do any other procedure, because it’s not available, or you do not have an expertise. Then transscleral cyclophotocoagulation or an endocyclophotocoagulation is definitely an option. But that you would want to reserve it for people where nothing else can be done, and usually we try and avoid doing this procedure for anybody who’s sighted and who has any amount of usable vision. We only take this as an opportunity to do it only if they do not have any useful vision, or as an adjunct when the first implant fails, before you decide to do a second implant. We’ll do something called a limited transscleral cyclophotocoagulation. We only choose to treat one quadrant, where up to about 10 or 15 shots are given, spots are given, where we try and limit the area, we try and destroy — ablate the ciliary processes, and that can be helpful to bring down the pressures to some extent, before we decide to do a major second surgery. So what are the challenges that we have in diagnosing and treating these children? Because the majority of them are asymptomatic. They have very minimal corneal signs, and they are not able to do their visual field tests properly. Intraocular pressure assessment is a difficulty. And they can develop at any age. And of course, the majority of them blame the corneal thickness to it. So in fact, I had a child who had a corneal thickness of 930, 940, whatever, and so this child’s recorded intraocular pressure was 32. So for an adult, we know that for every 15 microns of thickness, more thickness, beyond 520, you say you reduce one millimeters of mercury. So 900 and odd was the corneal thickness. So if you try reducing 11 millimeters of mercury, according to the Ehlers formula, you would arrive at an intraocular pressure which is quite safe for that eye. So I would suggest that that is not the way we use the central corneal thickness in children, because none of us know how to actually use any of these formulae, but we know that: Yes, if your CCT is high, you may be overestimating. But that doesn’t mean that the intraocular pressure should not be treated. They need to be treated as ocular hypertensives, and the pressures need to come down. So progressive increase in myopia, increase in the axial length, asymmetrical intraocular pressure between the two eyes, even if both the eyes are pseudophakic, and increasing the cupping. These are things that will give you a clue that there could be a possible ocular hypertension or glaucoma in this child. So how frequently do you follow up these children, once you have diagnosed them to have glaucoma? They require lifelong monitoring. So according to an editorial that came up in the British Journal of Ophthalmology, by Alex Levin, what he has said: That every three months during the first postoperative year, we need to follow up these children. After the first postoperative year, because the majority of them actually develop glaucoma less than one year of age. If they do not develop glaucoma less than one year of age, after that, twice a year, until their 10th birthday. Even if they haven’t developed glaucoma until then, they will still require a follow-up that will be an annual event. So I would like to repeat this again, every three-monthly, during the first year. Every six-monthly, until their 10th birthday, and thereafter, every year. So this is the routine that we follow. I’m sure several of these children who are going unnecessarily blind because of glaucoma can be prevented, and I think they have the… We have the responsibility to definitely do this for them. So I would like to wind up and summarize by saying that the incidence of glaucoma in these children is quite high. Majority of them are asymptomatic. One needs to understand what are the high risk factors that are responsible for glaucoma in these eyes. Just to recapitulate, that the younger age at surgery — severe postoperative inflammation that they have, the prolonged use of steroids, smaller corneal diameter, all of these are risk factors for these children to develop glaucoma. And lifelong monitoring is necessary. Unlike in other types of glaucomas, glaucoma medications are extremely helpful in the management of this — in raised intraocular pressure in these children. If intraocular pressure does not come down with medications, then trabeculectomy with or without mitomycin is a choice. Implants are definitely useful to control the glaucoma in these patients. However, none of these glaucoma surgeries, because of the young age of surgery, are going to work forever. So they also need to be followed up, even after surgery for glaucoma. And if additional medical treatment is required or additional interventions are required, they need to be followed up. And since all of you are pediatric ophthalmologists, I’m not emphasizing on the management of amblyopia and diagnosis and things like that, because you know that those eyes that have glaucoma, for some reason, have lesser vision, compared to the contralateral eye, have a higher chance of developing amblyopia. So they need to be treated, and of course, patching needs to be given right from the beginning. And if nothing else works, cyclodestruction is the last resort, but try to reserve that for the non-seeing eyes, or in those situations where no other intervention can be tried. Thank you. Okay. So the question is… One of the questions is: Are there any differences in incidence of postcataract surgery glaucoma due to surgical experience? Fellows versus consultants? That’s an interesting question. I guess it would be yes and no, because if there is somebody who is operating on a child, I’m sure they are quite careful in doing the procedure. I think actually one of our consultants, pediatric consultants here at LV Prasad Eye Institute, has looked at the outcomes of cataract surgery in residents versus consultants, but I’m not sure about the complication rates. Maybe I can look that up and send across the answer to you. The second question is: Is there a role for non-steroidal antiinflammatory drugs in steroid-responsive glaucoma? Yes, there is a role, but I think the children… So if we have to use steroids, because of increased inflammation in the early postoperative period, they do require steroids. So decreasing the amount of steroids or the frequency of the steroids or the strength of the steroids may not be a useful thing to do in them, because inflammation itself is not good for the eye. So that’s why I said: If there is severe inflammation, and if also there is a steroid response, how do we know that? Is it inflammation-related, or is it steroid responsiveness-related? We know that especially when you are operating the other eye. So it’s a very common example that we see, when one eye is operated and that eye — the operated eye has elevated intraocular pressure while on steroids, and in fact, by the time they come back at one month follow-up, they also have developed the Haab striae with that elevated intraocular pressure. And once we stop the steroids, it regresses. That also tells you that again, it’s possible steroid responsiveness. So when there is severe inflammation and there is a need for the use of steroid, yes, you can use it, but you can use additionally antiglaucoma medications. But nonsteroidal antiinflammatory drugs can be used as maintenance treatment. But not to reduce the inflammation in the acute phase, in the postoperative period. So the other question is: Can you use CCT as part of monitoring? Every 15 microns of CCT gives IOP off? Yes, this is exactly what I was trying to mention. That CCT in children should not be used the way CCT is used in adults. In children, I would use this as a parameter. For example, every child with a congenital cataract operated — be it aphakia or pseudophakia — is likely to have increased corneal thickness. Suppose I see a child who has, let’s say, 750 microns corneal thickness. I know that the corneal thickness is very high. And if the intraocular pressures are, let’s say, borderline, for example, 22, 23, I know that the corneal thickness which is high itself is responsible, possibly responsible, for elevation in the intraocular pressure. Having said that, if your contralateral eye is recording 14 or 15, you know that despite the corneal thickness being what it is, this difference in the intraocular pressure between the two eyes needs to be very closely monitored. Do not ignore that. On the other hand, I would not want to treat somebody with a 22 or a 23 intraocular pressure who has a corneal thickness of 700 or 750. Disc is fine, cupping, everything else is healthy, and the child is reading very well. I would very closely monitor, but not treat the patient. At the same time, I also use CCT to see how aggressive should I be in treating them. That means: Should I bring their intraocular pressure down to 10? 12? Or is 17 okay and 20 okay? I would be okay with bringing it down to a marginally borderline high intraocular pressure. It’s still fine. I wouldn’t worry about bringing down the intraocular pressures very low in there. There’s one more question. I need a clarification on the size of corneal diameter and choice of whether to implant or leave the patient aphakic. So do you want to take that question, Adio?

DR ADIO: Any horizontal corneal diameter of 10 millimeters or more needs to have an intraocular lens implanted. Anything less than 10 millimeters should not have an intraocular lens implanted in the patient. So that’s the horizontal corneal diameter. It should be measured. Okay?

DR SENTHIL: Yeah. So the other question is: Is there any racial risk factors for postcongenital cataract surgery glaucoma? I’m not sure. So once you all start collecting the data, maybe we should try and compare, to see what is happening. Because if everybody has the similar surgical technique, everything else is okay, but if the chance of developing glaucoma is more in certain eyes versus the other eyes, it is possible that there is some kind of a predilection. But at this point in time, I’m not aware of that. What is your experience in performing laser cyclophotocoagulation using an MP3 or a G probe? We do not have a G probe, but from what I hear from my colleagues and friends who have used them, they do seem to be working well. Similar to that of a transscleral cyclophotocoagulation. But they are very expensive. The disposable probes — extremely expensive. And again, just like your transscleral cyclophotocoagulation using a G probe, versus the MP3, the IOP control is very unpredictable. You cannot say: If I treat 90 degrees, I’m gonna bring down the pressures by 5 millimeters, or things like that. We cannot predict intraocular pressure control and for how long. How much and how long. That’s the question. So there is one more question, on how CCT helps in the diagnosis. I think I’ve answered that. When doing gonioscopy for the children, how do you manage their uncooperativeness? So if the child is cooperative enough for you to do an applanation tonometer, the child definitely will cooperate for gonioscopy. Several of the children, you just have to coax them and say: I will use a green light, blue light, yellow light, and things like that. And you have developed a rapport with them by then. They’re very, very cooperative. A 4 mirror gonio lens, especially after you’ve put a drop of proparacaine, they’re quite okay with it. If they do not cooperate, and if you have to take a surgical decision, I would not hesitate to take them under anesthesia, before I decide on the type of surgery and whether I really want to do it or not. And if I do, which technique. So again, your emphasis is more of trabeculectomy in this glaucoma. How often, when you choose to do trab-trab in these children? So trab-trab can definitely be tried, and all the younger children who are usually — there’s no cutoff like that. But I would say anybody who is 10 years or less, and who have an open angle on gonioscopy, we can definitely do a trabeculotomy with trabeculectomy. Combined procedure is what we try and do for every single child that we operate, but it depends on whether you are able to identify the Schlemm’s canal or not, and if you have significant peripheral anterior synechiae and you can not identify the Schlemm’s canal, we go ahead with the trabeculectomy. How frequently does one do a scan during follow-up of these children? Scan? I’m not sure whether you really mean the B scan, ultrasound B scan. Ultrasound B scan can be done, like I said, when you’re not able to evaluate — suppose there is a sudden decrease in vision, and the mom brings in — saying that’s the only seeing eye for the child. Especially if both the eyes are good, then one eye, if the vision goes down, they will not be able to pick it up, but if the parent comes, and you’re examining the child, the child is not able to read very well on one side, and you’re not able to figure out anything else, if you can see the fundus, it’s fine. If they’re not cooperative, there’s a peripheral retinal detachment or a choroidal detachment, you would want to rule that out, then we do a B scan. Otherwise, if we can’t examine the fundus once a year, we do the B scan ultrasound to rule out posterior segment pathology. After Berger space posterior capsulotomy successfully done, without primary vitrectomy, have you any risk of aphakic glaucoma? I’m not aware of that, because routinely what is done for us is a capsulectomy, as well as the anterior vitrectomy. What is your experience between AADI and Ahmed valve? What is the preference? So I think this month or last month’s Ophthalmology Glaucoma, there is an article that is published from our institute. In children, where we have used both the valved and the non-valved implant. And our results show that both the valved and the non-valved implant, the intraocular pressure control, as well as the Kaplan-Meier survival analysis, were almost similar. They were close to 78% to 85%. Having said that, with the AGV, the eyes required more number of antiglaucoma medications in the postoperative period, over a period of time. With the AADI, the number of postoperative medications required were far less. Intraocular pressure control was much better, compared to the AGV. But the eyes requiring interventions for early postoperative complications were more in the AADI group. That means the non-valved implants had more complications requiring intervention. For example, whether it is choroidal detachment or religature of the tube, because of prolonged hypotony, or things like that. Or one of the major problems we found was three of the children in the AADI group actually developed a cataract in the postoperative period. This was in the cohort which did not have cataract to begin with. But because of the chronic hypotony, I guess they developed cataract, and all the three children required cataract extraction. So that’s one of the problems. But yes, if the technique is okay, and if you are able to do it, AADI is really good. But they require a very, very close follow-up. That goes without saying. Gonio under GA. What do you use for magnification? If you use a Zeiss 4 mirror lens? We use the regular 4 mirror lens under microscope, and you can increase the magnification if you want to see the structures clearly, the way you will zoom up and zoom down. So no specific magnification thing that you will request. But you first put the gonio lens, and you will examine all the four angles. And if you see some abnormality, if you want to specifically look for certain things, you can zoom up or zoom in, and you can try to manipulate the lens a little bit for you to examine it more clearly. But otherwise, there has been no difficulty at all. Except for surgeries. That means if you’re doing a goniotomy, then I use a surgical gonio lens, which is a Swan-Jacob lens. But otherwise, routinely, for examination and evaluation, under microscope, examination in fact — two things that we have changed the way we practice. One is the gonioscopy. The other one is disc evaluation. We don’t use an indirect, unless the pupil is so small that you’re not able to examine. We use the same 78 diopter lens or the 90 diopter lens, even under the microscope, to examine the disc. Actually, you get better details of the disc with these lenses, just by moving the microscope up and down, and you can focus using these regular lenses. Do you have a problem with drowsiness with Iopidine? We don’t Iopidine with us, but what we have is the brimonidine. The age cutoff, like I said, is just an arbitrary age cutoff of 12 years, but if you ask me: Have you used it in anybody less than 12 years? I have used it. In desperate situations, when, if the child — the next step is to undergo surgery, I would rather use this, then perform the surgery. But what I would do is, if I’m using this drug for whatever reasons, I would ask the mother to do a punctal occlusion for them. So keeping the eyes closed for a couple of minutes, or doing a punctal occlusion, or putting the drop, when the baby is maybe half an hour or one hour before they wake up in the morning, would be a better choice. What is your experience with the role of PI in the control of IOP in aphakic patients? Yes. So actually, it’s very difficult to cover too many things in this, so that’s why I have not put in a lot of videos and things like that, but yes, recently I would say maybe a couple of months ago I had a child with aphakic glaucoma, and discs were very healthy, so whenever the disc is healthy, but the pressures are so uncontrolled, and not able to bring it down with medications, deeper anterior chamber, we’ve done the UBM, did not show anything conclusive, so when I took her, actually I had decided to do a trabeculotomy and trabeculectomy for the child. When I took her out for surgery, before I did the opening, on examining under a very, very high magnification, I realized that there was some amount of vitreous that I could see in the pupillary area. That gave me a clue that possibly there is a pupillary block, but we are not able to pick it up very well. So I made a paracentesis just with the same MVR blade, punctured the iris, you could actually see the iris going behind, so for that child, instead of doing a trabeculotomy and trabeculectomy, I did a surgical iridectomy, and removed all the vitreous that is there in the pupillary area. Until now, the baby is doing very well. Not even a single antiglaucoma medication the child requires. So you need to understand what is the mechanism of glaucoma. So for everything the solution is not just to use the drops and do any surgery. But understand why the pressures have gone up, and I think appropriately treating them would be helpful. Should we wait the child for two years old to implant an intraocular lens? Adio, you want to take that?

DR ADIO: So the usual thing with children looking at corneal diameter. Once the corneal diameter is within acceptable limits, and the child is old enough to have surgery, the anterior chamber is mature enough to have surgery, then we can put in an intraocular lens. But basically here in developing countries, because of issues we have with repeated surgery and all that, we like to leave the child aphakic, and then wait until the child is 4 years, and now put in an intraocular lens into the eye of the child. But generally worldwide it’s acceptable to put an intraocular lens in when the corneal diameter is at least 10 millimeters, the axial length is at least 17 millimeters long, and that is acceptable. I’ve talked about the peculiar issues we have here. So usually you do good aftercare, so that the child will have minimal repeated surgery, and then you use aphakic glasses, and then you put in the lens when the child is at least 4, when they can respond appropriately to checking the visual acuity and cooperate for doing biometry. All right. So we have come to the end of this very stimulating discussion. We had very many questions. And we want to appreciate Dr. Sirisha for taking the time to speak to us like this, and a little bit extra. We appreciate it. Thank you very much. God bless you, and from Nigeria pediatric ophthalmologists and everyone else, we want to say thank you very much. God bless you. All right. Bye-bye now, everyone. We hope to talk to you again in the next few months. And we hope you join us again. Thank you.

April 06, 2019

Last Updated: October 31, 2022

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