Lecture: Pediatric Ophthalmology and Strabismus Question and Answer Session

During this highly interactive, live webinar, Dr. Neely will be available to answer all of your questions related to pediatric ophthalmology and strabismus (adults and children). Live questions will also be accepted during the webinar, but priority will be given to those question submitted in advance.

Lecturer: Dr. Daniel Neely, Ophthalmologist, Indiana University, USA

Transcript

DR NEELY: Well, greetings to our Cybersight community. This is one of our question and answer sessions. And I really kind of like these, because it gives us an opportunity to give you information about what you really want to know, rather than us just telling you what we think you want to know. So it’s a nice opportunity to directly interact with you. The questions that we have have been submitted mostly in advance. And we’ll spend the first 45 minutes or so discussing the questions that we’ve already collected. And then I’ll take the last 15 minutes — I’ll take some of our live questions that come in during the seminar. Now, first of all, about me: I am the Cybersight medical advisor for Orbis, but I’ve been a professor of pediatric ophthalmology at Indianapolis for the past 26 years. And we have a long history of teaching fellows and residents in Indiana, and we’ve trained more than 110 fellows in the lifetime since Dr. Helveston started this fellowship. Some of those have been domestic and many have also been from overseas. So I’ve been doing this for 26 years. I’ve probably done about 10,000 surgeries at this point. And I’ve also been with Orbis for about 20 years, and have operated in… Oh… Maybe 13 different countries. So I have a fair idea of the problems that you face. So again, we had about 61 questions that were submitted during the registration process. Obviously that’s gonna be more than we can cover in the next 45 minutes. So what we will do is we’ll get through all that we can, we’ll do a few of the live questions, and then I will record webinar answers to the remainder of those, and we’ll post those in the Cybersight library. And hopefully maybe notify you which section your particular question is in. The questions are all deidentified. But I have included the country of origin. So that you can help sort out which ones are yours, and also — I think it’s interesting to see how vast the Cybersight community is. And that we all kind of have the same questions. And again, it’s the old adage: There’s no such thing as a dumb question. So this gives us a nice opportunity to dig into that. And with that, I’ll start with the one kind of case that was submitted. The rest of them are more general questions. But this one particular case… From Indonesia. The question is about a five-year-old boy who has had acute onset of esotropia for approximately 1 year. And it hasn’t changed during that time. Normal MRI, healthy child, but he has 30 prism diopters of esotropia. Which is comitant and also same distance and near. Normal visual acuity. No history of trauma or other complicating factors. Cycloplegic refraction is +3.00. And when he was appropriately given that full cycloplegic refraction, it didn’t really change his deviation. But he experienced some blurring of vision. With the full cycloplegic refraction. But he was actually relatively compliant with the glasses, so no change to his alignment but some detriment to his acuity. So the question from the commenter is: Is this acute acquired comitant esotropia or partially accommodative esotropia, and should I do surgery? So I’ll just back up a little bit here. Well, it’s both. Or maybe neither. Right? It didn’t respond to prescribing the +3s. So is this technically partially accommodative esotropia? Not really. If your measurements were the same before you gave them +3 glasses and after +3 glasses, and there was no change, then essentially there is no partially accommodative component to this. Maybe there was when it first started. Hard to know. We don’t have that information. But at this point, you have an ET that hasn’t responded to the glasses. And you see this quite frequently. And it’s always a little disturbing, because we don’t have an explanation as to why this starts. But this is definitely a known entity. This child had an MRI scan done. I will do that sometimes. But I’ve yet to find one of these kids who has an otherwise normal exam, normal motility, healthy child, no other symptoms — I’ve yet to find anything of interest on the MRI. So whether or not to get an MRI depends on your level of comfort with that approach. Depends on the family’s level of comfort. Depends on expense. There are lots of things. But I don’t think it’s something that has to be done. All right. At this point, though, you’ve tried the glasses. Didn’t work. Even though the child would wear them. What do you do? Yeah. I think at this point, that’s your option. You just proceed with strabismus surgery. Now, if he was… Had become intermittent, and this was a partially accommodative esotropia, then I probably would persist with the glasses. If he had at least become intermittent. But that’s not the case here. And so you move on to surgery. This is a normal stepwise approach to things. Next question, from Ethiopia. Should we give a unilateral bifocal add to a unilateral pediatric cataract patient after surgery or let them do monovision for reading? Well, the answer is going to be all over the place on this. And some of it depends on the patient’s age for me. When you have an infant, unilateral cataract, preferred approach, if possible, is the contact lens, where you might be overplusing them. So you’re making them a -3 up close. And you would do that temporarily, until you could switch them to glasses. Now, if you — once you place a patient into glasses, then — and an approach to an IOL would be the same as with a contact lens. Once you have them in glasses, now you’re giving them correction, which is in general for a unilateral cataract going to be for distance fixation. Right? And then you’re gonna want them to have a bifocal in place. At least during the years that they would be sensitive to amblyopia. Now, after age 7 or 8, I think you can do this any way you want. And I do that. Some kids, I’ll keep them in a bifocal. Other kids, they don’t like the bifocal. Maybe they even have amblyopia, where they’re not really using that eye very much. And in those kids, I’ll take the bifocal out, just to simplify things, and let them use their non-surgical, non-cataract eye, which has accommodation, to do their near work. So I think at least for the amblyopia age group, you want them to have near acuity, one way or another. Whether it’s overplusing them on their contact lens or giving them glasses with a bifocal. And after that, you can kind of decide what’s gonna work best. Third question, from South Africa. 11-year-old child with poor near and distant vision. Bilateral exophoria on cover/uncover test, that becomes alternating exotropia. Presumably a manifest exotropia. So there’s some information we don’t have here. We don’t know why they have poor vision. But my approach to these kids — a lot of times you’ll find that they might be myopic. And if they have vision that’s correctable with a myopic correction, I think you want to give these intermittent exotropes their full correction. You might even consider overminusing them, although I’m not a huge fan of that. But at least give them their full myopic correction so that their vision is clear. Once you have their vision clear, then you reassess their strabismus and determine what their level of control is. If the control is satisfactory, you just simply observe. If their control is still quite poor, and you have this manifest alternating exotropia, then it becomes a surgical issue. So you control what you can. And if their vision is correctable with glasses, you go that route. If their vision is not good for other reasons, there’s some ocular pathology, then you just have to decide based on their level of control. This was an interesting question from the UK. And this question has to do with papilledema and anomalous optic nerves. And this is probably one of the more frustrating and difficult things to sort out in practice. And we see a lot of patients for anomalous optic nerves. In this particular case, we have a 16-year-old, who is known to have stenosis of the transverse sinus. They also have optic nerve swelling. But they’ve had a normal lumbar puncture, presumably this means a normal opening pressure. And then the question is: Is the stenosis of the transverse sinus related to the optic nerve swelling? Why does this even come up? Well, there have been articles such as this one, from the American Journal of Neuroradiology, where transverse sinus stenosis is highly linked to idiopathic intracranial hypertension. And in this particular study, they looked at something in the ballpark of — I think it was 90 cases that were known to have intracranial hypertension, and 60-some cases that were controls. And they found that 94% of those with idiopathic intracranial hypertension had transverse sinus stenosis. Whereas only 3% of controls did. So at least in the US, one of the evolving treatments for intracranial hypertension is stenting of the transverse sinus stenosis. And those seem to provide pretty good results. However, it becomes confusing when in this particular case, when you’ve had a normal opening pressure on the lumbar puncture, so now you have anomalous-looking nerves, and a normal opening pressure. And then there’s finding of transverse sinus stenosis. Well, you can have that. Just as a coincidental factor. Where they found this in 3% of controls. So when you see these kids with anomalous optic nerves, you need to start deciding: Do their symptoms correlate with intracranial hypertension? So do they get obscurations of vision? Do they have headaches that are daily, throughout the day? Have you done a B scan to rule out the presence of drusen in the optic nerves? I see that all the time. That anomalous optic nerves with drusen get called papilledema. And I think there’s a question of… You know, you’re not going to have a normal lumbar puncture opening pressure at the same time you’re gonna have swollen optic nerves from increased intracranial pressure. So if those two things don’t jibe, one thing I might consider in this case is repeating the opening pressure, if you really feel like this is papilledema. And also the other thing that could be tried is: Do they respond to Diamox? Acetazolamide? If they respond to acetazolamide, then there is some evidence that maybe there is elevated intracranial pressure that’s not being identified on this lumbar puncture. So this becomes a real mishmash of just clinical trees that you need to sort out. Fifth question, from Ghana. We have a child who has had two surgeries for alternating exotropia. But they still have exotropia. And why is that? Well, we don’t know. There’s so much about the origin and variability of strabismus that we don’t know. And we all make up reasons. But the truth is we don’t know. And some of these large angle exotropia patients — or even, you know, it’s understandable if someone has 60 to 90 prism diopters of exotropia, why they may not be straight after two surgeries. But I see this happen sometimes in kids that have 25 or 30 prism diopters of exotropia. And you do your normal bilateral lateral rectus recession. They only get a little bit better. And then you go back and do medial rectus resections or plications, and yet they still have residual exotropia. So it’s a frustrating thing. I don’t think it’s something that you can predict in advance. The bottom line is: We don’t know, and you just deal with what you have. So if I’ve done maximum lateral rectus recessions, and I’ve gone back and then done medial rectus resections or plications, I would go back and I would re-resect, or re-plicate one of the medial rectus muscles as needed. And so you just… Like in so much of strabismus, you just deal with the cards that you’re dealt. Next question — wasn’t much of a question. Was just two words: Adenoviral keratoconjunctivitis. But I left it in here, because recently in the last month or two, I have seen tons and tons of kids with viral — what looks like normal viral keratoconjunctivitis. But I think it’s also of note that keratoconjunctivitis has been associated with COVID-19. To the point where we’re starting to forget about COVID-19 — it seems like it’s in the background now, and history, but we’re identifying some of the associated issues with COVID-19. And it may present initially as a keratoconjunctivitis. That may present three or four days before someone becomes symptomatic, otherwise. So I just throw that out there, as something to keep in mind, given that association. Next question. From Saudi Arabia. And this is one that comes up all the time. Right? We have fellows, we’ve trained more than 100 fellows, and they all want to know about adjustable sutures. Well, I will start by saying that in my practice, we have eight full-time pediatric ophthalmologists. Strabismologists. None of the eight of us have chosen to do adjustable sutures on a routine basis. Just not overwhelmingly impressed with it. But you will find other places where everybody does them, and they do them on every single patient. Even kids. So… There’s this divide and bias that’s out there in the world. The problem is… We really haven’t been able to prove if one way is better than another. And this particular paper — this was one of the Cochrane database reviews. They also looked at Ovid and PubMed, and basically this is a big review of looking at studies that compared adjustable to non-adjustable. The bottom line was: The authors in this review article really couldn’t find evidence one way or another. For adjustable versus standard strabismus sutures. They also could not identify any subset of patients where adjustable sutures had an advantage over non-adjustable. I don’t know the answer. But I do think that the truth is probably somewhere in the middle. Okay? I do think that there’s probably a subset of patients where the ability to adjust them post-op might be helpful and have some advantage. The question is: Is it worth the downsides of doing this on a routine basis? Takes more time. There’s more patient discomfort. So this is a balancing act. And at the end of the day, I’ve decided, personally, that it’s not something that I find to be terribly helpful. But again, even though I’ve been doing this 26 years, a lot of what I’m telling you is personal preference and opinion. Bottom line: I don’t think that we know the answer. If there is a difference, it’s probably not a large difference. Otherwise I think we would know it by now. Next question from Nigeria. This is a little vague, but: After the corrective measure of strabismus, the eyes don’t see well. What should be done? Well, just some general points here: Strabismus surgery does not change your vision for the better or for the worse. So… You know, you can have people who — they had double vision that was further apart before surgery. And now it’s closer together after surgery. And if that’s what’s affecting their vision, this kind of blurring or doubling image, then maybe they would benefit from additional surgery or prisms to fine tune that. But if you have someone — aside from that, if you have someone who is not seeing as well, you need to look for refractive issues, some people can get induced astigmatism from strabismus surgery. You need to look at their corneas. A lot of times, if they’ve had a lot of edema of the conjunctiva, they might be developing a dellen or irregularity of their tear film. And those are the things I look for in someone who is complaining of their vision postoperatively. Next question from Pakistan. And this is about alternate patching for different types of strabismus and amblyopia. Once upon a time, I used to do a fair amount of alternate patching. Either for intermittent exotropia, not so much for amblyopia. You know, I’ll address that topic first. If someone has bilateral amblyopia, both eyes 20/60, there’s really no advantage to patching one eye and then the other the next day. Right? The treatment for bilateral amblyopia is to correct the refractive error, and then monitor the acuities to make sure that they stay equal. But you’re not going to speed up the improvement by patching one eye one day and the other eye the next. Okay? So it doesn’t really apply to that. For strabismus, I personally didn’t see much benefit to it for intermittent exotropia. I don’t feel like their level of control was improved. Families would sometimes think that it was better, but it was hard to really back that up when they were seen in the office. About the only time I might use this currently is for infantile esotropia, while I’m waiting to get them into surgery, if they’re just a few months old, perhaps. But honestly, if they’re alternating, then you don’t really need alternate patching. And so these days, mostly my patching is restricted to monocular patching, when I sense if there’s amblyopia of one eye. And that’s about it. Next question or statement from Romania was just: Antielevation syndrome? So what is antielevation syndrome? Antielevation syndrome is when someone has had surgery on the inferior oblique. Most notably, if they’ve had an anterior transposition of the inferior oblique for dissociated vertical deviation. DVDs. And some people will be noted to have a limitation of elevation after they’ve had their inferior oblique anteriorly transposed. If that happens, then you simply want to go back and either do less anteriorization — you know, so anterior transposition can be anywhere from 1 to 2 millimeters above the insertion, anterior to the insertion of the inferior rectus. Or it can be as little as… At the insertion of the inferior rectus, or 1 or 2 millimeters inferior to it. And so if someone has antielevation syndrome, and they’ve had a +2 transposition, you might back it off a little bit. Or you might convert it to a recession. And that’s probably the most typical scenario that you see. Next question, from the Philippines. And this is about prisms. Are eyeglasses and prisms enough for the treatment of strabismus? Well, it depends. Right? I mean, I almost never use prism for anyone who doesn’t have diplopia. Most kids aren’t diplopic. And about the only time I use them in children is — say they have surgery for exotropia and they develop a consecutive eso deviation. I might use them if they’re having some diplopia or I worry about them suppressing because of amblyopia. But other than that, I find that the use for prisms in children is minimal. Their deviations are usually so large that you couldn’t — you can’t fix 30ET or 30XT with prisms. So the big category for me with prism is adults. If someone has small vertical or small horizontal deviation, and they’re symptomatic or diplopic, I’ll give them prisms. But there’s some practical considerations. I see some people come in, and they’ve got 15 prism diopters of base in or base out prism. And these giant thick glasses that they’re totally unhappy with. Because there’s so much distortion. They’re heavy. There’s distortion. From a practical standpoint, people don’t really tolerate more than maybe 8 prism diopters of ground-in horizontal prism. And for vertical, it’s probably even less. It would be uncommon for me to use more than 4, maybe 6 vertical prism diopters. If someone starts to get more need for larger amounts of prism than that, we’ll use a Fresnel press-on prism sometimes. But I see those as a temporary approach. And ultimately, if you have more deviation than what you can easily put into prism glasses, people just need to have surgical correction. So I would push the amounts of prism for people that don’t want surgery or aren’t good surgical candidates. But other than that, I think they’re used mostly just for fine tuning or very small deviations. Another question from the Philippines — different person, but similar question — are prisms really important to correct strabismus? No. Again, basically they are important for adults with small symptomatic deviations. Either in place of surgery or to fine tune things after surgery. But giving someone more than 10 prism diopters of prism is not really doing them any favors. And not really a great solution to things. Those people probably just need surgery. Next question from Yemen. At what age do you prefer operating on a child with infantile esotropia? So congenital esotropia, infantile esotropia, there’s not a lot of evidence about the timing here. We do know from some of the published papers, 30, 40 years ago, even, that maybe after age 2, there’s a decreased likelihood of having stereopsis, or maintaining fusion over time. Peripheral fusion. But… So there became a push to do ultraearly surgery, like in the first few months of life. And I don’t think we really saw that that was particularly helpful either. And it’s really difficult to know how much surgery to do in a three month old, or even a six month old. The measurements are complicated. The eyes are quite small. The surgery is a bit more challenging. And certainly anesthesia risks are significantly more. So my general approach is to go somewhere in the middle. I like to get these kids operated on by about a year of age. Now, what factors might modify that? I think it would come down to anesthesia safety. I’ve certainly worked in a lot of places around the world where the anesthesiologists were not comfortable with kids under two years of age. And if that’s the case, it’s not worth trying to take them to surgery. You wait ’til they can safely have their surgery. Because what’s the plus side of getting a great result from infantile esotropia? Plus side is maybe they have better stereopsis outcome. Maybe they have a lower rate of reoperation. Maybe. Fact is… It doesn’t matter for most of these people. You mostly go in for what’s probably gonna boil down to minimal stereopsis. Good cosmetic results. And on average, these people are gonna have a couple surgeries — probably almost no matter what you do. So… I think the benefits are soft enough, you have to look at the safety side of things much more than you do the visual outcome side of things. Next question from Tanzania — at which refractive power for myopia or hyperopia do you decide to offer spectacles for children? Well, this becomes age-based. Clearly what you want to do for a 2-year-old is a lot different than what you need to do for a 12-year-old. Older kids, you’re basing the decision to give them glasses on what they need for school, most likely. Or to drive a car, as they get to be teenagers. So usually that level of myopia is about a -1.5. The hyperopia really just depends on whether or not they have any esophoria or intermittent esotropia-type tendencies, or do they have any discomfort or near vision-type symptoms? So there’s a lot of variability with hyperopia. And older kids — some can tolerate running around with no glasses and be a +5, and some can’t. With the hyperopia, again, if they are above the age where they’re sensitive to amblyopia, you can really kind of pick and choose based on symptoms. The age for that is probably gonna be — for me, the ballpark is around 7. I don’t worry about kids older than 7 getting amblyopia. And the truth is, a lot of kids even by 5 or 6, they seem to be pretty locked in. There’s some variability there. And there’s a wide range. But 7 is kind of my rough ballpark for amblyopia sensitivity. Okay? Under that age, from 0 to about 7, we are looking at giving kids glasses based on the danger of them developing amblyopia. So for myopia, if it’s bilateral, you almost never really have to get too excited about it. But I would probably correct if someone was more than a -3. And they’re 4 or 5 years old. That’s a pretty short focal distance. But I think a 1-year-old who is a -3 is probably just fine. With hyperopia, our guidelines for giving people glasses to prevent amblyopia is more like… +3.50 ballpark. It’s probably more of a concern if it’s anisometropic. Unilateral high myopia is very damaging. But pretty big differences, in that case. Versus hyperopia, where even a difference of 1 prism diopter between the two eyes can be amblyogenic. So there are guidelines for this. If you look at the APOS website and the vision screening guidelines there, you can see what the APOS guidelines are officially. And I think that those are all pretty reasonable. And I’ve had some role in developing those in the past. So I would look to that, if you really want concrete numbers. Another question from Tanzania. What is the best surgical technique for a pediatric patient with nystagmus, combined with esotropia? Well, first of all, just talking about nystagmus surgery — nystagmus surgery, in general, if you’re just talking about dampening the nystagmus, is controversial. And I do it. I do four-muscle recessions. I do four-muscle tenotomies. I’m more likely to get excited about doing null point surgery. I think that you definitely see some impact with that. But when you’re talking about improving someone’s visual acuity with four-muscle recessions or tenotomies, the results are pretty modest. Maybe you get one line better. Maybe you have an increased recognition speed. But it’s pretty soft. But if you do have a patient who requires surgery for esotropia, as is being asked here, do I think it’s reasonable to go ahead and do something that might help the nystagmus as well? I do. So what could you do? Well, an easy thing to do in this situation, I suppose, would be to do your normal surgery for the esotropia. But then do tenotomy surgery on the lateral rectus muscles. What do we mean by that? We mean simply disinserting and reattaching at the exact same position. All right? How does that work? Well, it’s hypothesized that it’s disrupting the efferent pathways and the neural network, and that’s how you get your dampening of the nystagmus. Some people believe that. Some people don’t. But that’s an easy way, if you’re in the — yes, I believe that category, to take advantage of that. It gets a little more complicated when you want to do actual four-muscle recessions. Because now you have to try and estimate: How much are you gonna do for the esotropia? And then what are you gonna do with the lateral rectus muscles to compensate for that? And I just think that gets pretty messy. I’m not a big fan of that in particular. But it can be done. With the newer evidence for tenotomy and reattachments, I probably would go that route. I just think that would be more predictable, in terms of not changing someone’s alignment for the worse. Question 16 comes from Colombia. And I apologize, but I did use Google translate. So the Google translation is: How to treat marked primary bilateral inferior oblique hyperfunction. Or overaction. So… How to treat primary bilateral inferior oblique overaction. What do I do for that? For that… Inferior oblique myectomy is usually my go-to. If I’m gonna operate for inferior oblique overaction, it’s usually gonna be relatively significant. So we grade — we just arbitrarily grade inferior oblique overaction on a scale from 1 to 4. +1 would just be a little bit of overaction. +2 and 3 would be moderate amounts of overaction. And a +4 is significant amounts of overaction. If I’m gonna operate, it’s usually gonna be easily for a +2, 3, or 4. So I need a fair amount of weakening, and it’s typically for me going to be inferior oblique myectomy. Inferior oblique recessions I use much less commonly, and if I do, it’s usually for mild superior oblique palsy, or I’m combining it with a mild horizontal surgery to decrease the inferior oblique overaction. Next question, 17, from Moldova. Consecutive divergent squint. Which surgical approach to choose? So what I’m interpreting from this is that someone has had esotropia surgery, and has developed a consecutive exodeviation. So this is a relatively common surgical scenario. How do you deal with this? Well, you look very closely at the medial rectus muscles which had the first surgery. If it looks like the versions are full, and that there’s no underaction of the medial rectus muscles, then I think you can do whatever you want. You can probably — really easy just to recess the laterals for your standard surgical numbers. However… If there’s any question at all that the medial rectus muscles look to be underacting, or if you have some incomitance that you can document, then I think you have to go back and take a look at those medial rectus muscles. There’s a good chance that they are slipped. There’s some empty capsule or stretched star, whatever you want to call it. Once you look, if you see that, you need to resect that empty area, that slipped area. And put it back to where you think the muscle is supposed to be. However, if you look at those medials, and they look fine, they’re exactly where you put them, well, in that case, you can still advance them. Just reverse some of the surgery. So it’s kind of no harm done. So it really depends on what the medial rectus muscle function looks like. You have to look at those ductions and decide: Does the motility look full or not? What you don’t want to do is ignore underacting medial rectus muscles, and just take the easy way out and recess the laterals in that case. The patient will be undercorrected or only temporarily corrected, and you’ll be back there doing the medial rectus revision anyway. Question 18 is from Honduras. And again, this is a Google translate version of the question. When should we consider strabismus surgery in a pediatric patient? Or what are the surgical criteria? Well… This is a big question here. Because there are so many variables with this. Right? You consider strabismus surgery when someone’s level of control is either placing them at risk for amblyopia or they are cosmetically unacceptable, or they are having functional symptoms. Right? It boils down to kind of those three things. So in an older child, you know, a lot of this is subjective. You have to make a decision in concert with the child and the family to see how they feel. In a younger child, then your surgical criteria are: Do you think that they’re developing amblyopia? Or do you think they’re at risk for amblyopia? And then you modify that, based on the anesthesia risks that we talked earlier. You know, it’s a lot different if you’re gonna take a six month old to surgery for general anesthesia versus a six-year-old. So all of that gets put in together to your decision. Question 19 is from Greece. This is about double elevator palsy with Marcus-Gunn congenital ptosis. What is the best treatment? I’ll start by saying I hate Marcus-Gunn congenital ptosis. I hate it, because it’s very difficult to have good results with it, in my experience. I’ve tried just doing levator resections, I’ve tried doing levator extirpations. I really didn’t like that. And it’s one of those kinds of ptosis that just in itself — this is separate from the double elevator palsy question — but just in itself, I really honestly try not to operate on the Marcus-Gunn congenital ptosis patients. They seem to look better over time. Because they kind of subconsciously figure out the relationship between the mouth position and the eyelid position. So they do look better over time. If someone has just a little bit of jaw winking, I think you can pretty much treat them normally and do levator resections. If someone has a really large jaw wink component, the concern is… If you do a levator resection and lift that up, now you’re gonna see sclera above the limbus, and that does not look good. That looks worse. All right? And those are the ones where it’s recommended to do levator extirpation. However, a levator extirpation means you have to put in a frontalis suspension. It also means you’re at risk for disrupting the superior fornix. So it gets quite messy. And that’s why I really try not to operate on those if I can. Double elevator palsy — approach to that, in isolation, is pretty straightforward. You take them to surgery. And you do a traction test. You do forced ductions. Right? If you feel that that inferior rectus on that eye is tight compared to the other eye, then you need to recess that inferior rectus. They have a fibrosis or restriction. However, if their passive ductions to elevation are totally unrestricted, and it’s equal between the two eyes, but yet you have no elevation, because the superior rectus is not working, then my approach to that is to do a vertical transposition. Usually a full tendon with transposition, of the medial and lateral rectus muscles. I simply move them up, so that they’re now adjacent to the corner of the superior rectus insertion. Right? Following the spiral of Tillaux, more or less, and getting your elevation in that regard. If you have them both together, I would probably hopefully just do the treatment for the double elevator palsy and sit tight on the Marcus-Gunn ptosis. And also because you have to keep in mind — once you do the strabismus surgery, any pseudoptosis component that’s there is going to improve. When the eye is hypotropic, the eyelid follows it down. So the ptosis looks worse. Once the eye is more centered in the primary position, the ptosis is actually going to look better. So you really hate to do vertical strabismus surgery and ptosis surgery at the same time. And you certainly don’t want to do them in reverse order. You don’t want to do the ptosis surgery first. You want to do the strabismus surgery first, and then decide if you still need the other. This is number 20. We have 60 questions total. So if I break them down into three sets of 20, that will give us three sessions that will be recorded. Also, when I mentioned that these are going to be recorded — it’s going to be just like this. It’s going to be the question. It’s going to be me talking. And all of this gets transcription with it. So that you can read what I’m saying to make it a little bit easier for a lot of our audience. Okay? And it also will make it easier to find your particular question. Because we have — they’re all in here. We just don’t have time to get to them all. Last question from Paraguay. Again, with my buddy Google translate: Does the genetic factor predispose to the disease? Does esotropia require immediate attention? So we’ve talked a little bit about the timing for esotropia. It doesn’t require immediate surgical correction in infants, if that’s the question. Right? I do think that the less time… Talking about maybe particularly with refractive accommodative esotropia — the less time it takes to get them into glasses and corrected or surgically corrected, probably the better off they do. Kids that start off having intermittent eso deviations start to have constant deviations. And I think you really want for acquired esotropia — you really want to limit how long someone has a constant esotropia. You want that corrected in a timely manner. Whether that’s going the route of glasses or going the route of surgery or doing them both in sequence. The genetic factor? Yeah. You certainly see some families that have infantile esotropia or Duane syndrome also in multiple generations. It’s not the rule, but I have definitely seen that happen several times. It’s much more likely that you have a strong genetic factor when it comes to refractive accommodative esotropia. And one of the things you’ll do is you’ll see a teenager. A new teenager. Right? And that teenager is suddenly found to have amblyopia, either because of anisometropia or strabismus. Well, you certainly want to warn that teenager that when they have kids, that they should probably have an eye exam at a young age. Maybe 2. So you can see if they have anisometropia or hyperopic predisposition. Likewise, if you’re seeing a 4-year-old, and you identify that they have anisometropia or perhaps refractive accommodative esotropia, you need to ask if there are other young kids in the family. And if there are, you want to have all of them get examined to see if they’re also at risk for developing refractive esotropia. Or amblyopia. So that’s my word of caution, when it comes to that. All right. So… I will… I’m gonna stop the share here. So that I can open up the chat questions. And bear with me while I open these up. Okay. So I’ll go through these in the order that they’ve been submitted. We’ll do this for the next 14, 15 minutes. This question is from Pakistan. And the question is: If a patient has both DVD manifest and hypertropia — so they’ve got a manifest — they’ve got DVD and a hypertropia — how do you differentiate both on the basis of the cover/uncover test? All right? So you do see this sometimes. And it’s certainly intimidating. Because you can’t really measure a DVD. Right? You can identify it, but you cannot measure it very easily with prisms. Some people will. I’ll tell you, it’s not very easy. So what you’re doing is — when you have a vertical deviation and you’re doing your alternate cover test, one eye is always gonna go up. The hyperopic eye — the hypertropic eye is always gonna be coming back down. Right? So that’s gonna be the same with DVD or hypertropia. But the contralateral eye, if you have a DVD, it’s never coming back up. Right? If you have a manifest deviation, one eye is going up, one eye is going down, and they’re switching back and forth. But if you have a DVD, just one is doing this all the time. So what you do is you put vertical prisms until this alternating hypertropia stops. And then now you’re just gonna see the DVD. So you have a prism number for the hypertropia, and then you have an estimate, +1, +2, +3, for the DVD component. So then you can do your surgical estimation based on that. Next question: What is the management approach to pediatric diplopia? Well, pediatric diplopia, I think I would treat that the same as adult diplopia. We touched on this a little bit. You know, fortunately, it’s relatively uncommon that kids have diplopia. And if they do have it, it’s uncommon that they’re bothered by it. So if someone has a large degree of diplopia, deviations that aren’t amenable to prism, then you either need to do surgery or… Well, you just need to do surgery. If they have small degrees of diplopia, or you’re trying to buy time, to see if, say, there are consecutive esotropia after bilateral lateral rectus recessions from exotropia… All right? So if you want to buy time, then you might give them prism, while you’re waiting to see if that consecutive exodeviation resolves. So this is a… I might even tolerate larger deviations with Fresnel prisms, while I’m waiting to see what happens, before I decide about reoperating. But again, the most amount of prism I’m going to give someone is gonna be in the ballpark of 8 prism diopters or less. If someone has a need for more amounts of prism than that, you’re probably looking at surgical intervention, rather than prism. Next question… Patient has more than +5 hyperopia. But is having exotropia. What do you advise about the glasses? You see this, and it’s always kind of weird. A couple ways to go about this: Intuitively, you’re like, I don’t want to give them +5, because they’re already exotropic. So in this case, we’re not gonna push +5s on them. If you were… It would be helpful to know what they are with no glasses. If they’re a +5, but they’re XT with no glasses, then simply giving them a little bit less plus is probably not going to be helpful. So what I would probably do in this case is give them something to get them into a physiologic range. Most kids can tolerate being a +1, a +2, a +3. So I would probably take 2 diopters, 2 or 3 diopters, off of what this patient’s refraction is. And so I might be giving them a +2 or +3 glasses. And then remeasure them in the office to see what their exotropia is, and then probably operate for that. That’s different than if this person is a +5, but you give them… But they’re not exotropic. Right? You have to go a different approach. And sometimes it’s trial and error too. But that’s probably what I would do. They probably need surgery. But you probably need to look at them with a partial amount of hyperopic correction, before you decide how much surgery you’re going to do. Realizing also that their hyperopia is going to improve over time. If this child is 8 years of age or less. Next question: Is there any role of spherical glasses in hyper or hypotropia? So glasses for myopia or hyperopia for vertical deviation? I would say that the only role would be if you feel like their vision is blurred, and making the vertical deviation worse. All right? So otherwise I don’t see any real significance to it, unless you’re choosing to put prism into the glasses. But giving someone a -3 or… For hypotropia… Is probably not gonna make any difference. If they have a DVD component, as part of their hyperdeviation, if they have a DVD component, you want them to be seeing as well as possible. So it does play a role when you’re talking about DVDs becoming manifest. So you want the best possible acuity. Next question: Do you expect some response after a few weeks of spectacle prescription? Yes. So if I see someone that I think is a refractive esotropia, and they’re a +4, or +3.50, something in that ballpark, I will give them glasses. Ask them to get those glasses. Takes about a week to get glasses made. Ask them to wear the glasses full-time. And I will see them about six weeks after I have prescribed the glasses. At that point in time, we’re looking to see if they have amblyopia. If they do, we start treating that. If they don’t have amblyopia, but their strabismus is still present, then I feel comfortable making surgical decisions at that visit. Okay? As a general guideline, if someone has amblyopia, you want to treat that before the strabismus surgery. Sometimes it doesn’t work out that way. Or sometimes you’re doing it all at the same time. But as a general guideline, I would say that that is preferable. Next question is: Spectacle prescription. We talked a little bit about thresholds for that. I won’t go back to that. If you would like to know general guidelines for spectacle prescription, go to the APOS website. Vision screening guidelines are there. Those are roughly vision — spectacle prescribing guidelines. You can also go to Cybersight. And go to the modules, the courses on pediatric ophthalmology and strabismus. The basic module — I think it’s module 1 — has prescribing guidelines. Has my personal prescribing guidelines for pediatric patients. So I would refer you to the Cybersight library courses for that. Next question is… Pediatric patients age 2 to 5 years, with exotropia or esotropia. Having normal vision and normal refraction. Should we advise some low power glasses or go for squint surgery? Well, normal becomes somewhat vague. Because there are some kids in this age group — 2 to 5 years — who might only have a +2 refractive error, and have esotropia, and that’s not normally a refractive error that we think is going to cause accommodative refractive esotropia, but some of those kids will actually respond to that. So there’s not… I can’t say that there’s a hard and fast rule for that. If someone is hyperopic, and they have an intermittent eso deviation, I would probably try glasses just about no matter what. If they have a manifest deviation, and they’re +2, and the deviation is 40 prism diopters, I probably wouldn’t even mess with glasses. That’s probably not gonna happen. So there’s a little bit of common sense. But there’s also some borderline cases, where you might not normally give those glasses, but you’re gonna try them. For exotropia, I think it really boils down to if they’re… Like, one of the previous questions: Are they a high hyperope? And they just have given up on accommodation and they’re blurred? And that’s why they’re exotropic? Yeah. You probably want to correct some of their hyperopia to see if improving their vision and their accommodation straightens their eyes. Or if they have significant myopia. And by significant, more than 1.5 or 2 or 3 diopters — you probably want to try glasses for those, to see if it improves their exotropia. So… Rough guidelines there. Next question: 6-year-old with alternate exotropia. Good control for near. Moderate to poor control for distance. Good stereo for near and poor stereo for distance. Would you consider surgery? Any role of fusion exercises? Fusion exercises… Get asked about that. And vision therapy. Quite a bit. I think it can help a little bit. And some families are very motivated to do it. And in those families, I will assist them with that. I would say that 95% of the time people don’t do it. Or they don’t keep doing it. And it doesn’t help. So I think you have to be very selective. A 6-year-old with alternate exotropia… Good control for near… They’re fine. I mean, you could watch that kid as long as you wanted to. I think you have to decide — because they have good stereo and good control for near, I think you have to decide: Do they need it for cosmetic reasons? Do they need it for stereopsis reasons for distance? A lot of times sports comes up as a reason. But a kid like that, alternate good control for near, you could sit on that forever. There’s not a party line answer on that one. Here’s another question about patching for bilateral amblyopia. What is the role of patching in squint if the vision is the same in both eyes. To me, there’s no role. If I have bilateral moderate to mild amblyopia, I am not going to get better doing this one day and this the next day. The treatment for bilateral amblyopia, if they truly are equal, the treatment is optical correction. Fix whatever caused the amblyopia. I’m sure there are people that disagree with that. But I don’t think you’re gonna find any proof that alternate patching or bilateral patching is gonna speed up equal bilateral amblyopia. What is the best surgical approach to correcting exotropia greater than 100 prism diopters? Yeah. Exotropia greater than 100 prism diopters? I don’t know that there’s a best surgical approach. This is gonna be a tough one no matter what you do. When you get up into this range, you’re gonna do maximum surgery. And you’re gonna see what you get. There’s no table for 100 prism diopters. What would I do? Oh, I suppose I would… I wouldn’t work on the obliques. Some people would do oblique surgery for these larger deviations. I think if I had a patient 90 to 100 prism diopters of exotropia, I probably would recess the laterals a large amount. 8, 9 prism diopters. In that ballpark. And I would do large plications of the medial rectus muscles. That’s gonna be 7-ish millimeters. And if I needed to do more, I would go back to the medials, and I would resect or plicate them more. Wouldn’t be surprising that this is a surgical correction that’s gonna take two surgeries. I think you’re unlikely to overcorrect them. But I would be hesitant to do these giant lateral rectus recessions, where you start doing 9 and 10 and 11 and 12 millimeters. I tend to shy away from that. More likely to tighten the medials. Question about the ideal age to correct strabismus. I think we talked about that a little bit already. So I won’t go back to that one. A couple more questions. It’s the top of the hour. I’ll call this a day. 12-year-old girl, unilateral corneal edema for one week. Associated with poor vision but no pain or photophobia. No tearing, no redness, no history of trauma. Vision is 6/12 and intraocular pressure is normal at 14. No corneal staining with fluorescein strips. How should we manage such a case? We clearly don’t know what the cause of this corneal edema is. Right? So what are gonna be the common causes? Well, glaucoma. But not in this age group. It would be a younger kid. HSV, HZV, with corneal stromal edema. And endothelial cell dysfunction. I think that’s probably a pretty good candidate in this case. I probably would try treating this kid with acyclovir. Endothelial cell dysfunction and corneal edema — you treat that with hyperosmotics in the setting of normal pressure, trying to clear the cornea. But I think really the question is here: Why do you have endothelial dysfunction? Right? Doesn’t sound like this is keratoconus. But again, that could give you a hydrops episode. So looking at corneal curvature is probably indicated. I think those would be my two big things. Of corneal curvature to rule out keratoconus, and maybe a trial of acyclovir, if this is herpetic-related. And not epithelial disease. Rather, it’s stromal endothelial disease. Last question. And this is: Have you encountered the coexistence of superior oblique paralysis and Brown syndrome in the same eye? If yes, how do you plan your treatment? So yeah. That’s an interesting… So you’re talking about two kind of opposite things. A Brown syndrome, but yet superior oblique paralysis. Well… I don’t think I have. I’m trying to think how you could possibly have both. Or at least how you could identify both. Certainly with Brown syndrome, you could have limited elevation of the eye. So how are you going to identify a superior oblique palsy at the same time you’re identifying a Brown syndrome. I don’t know. Honest answer is I would have to think about that. I just can’t see how that would… Those are two opposite things. I don’t really see… It would make me question the diagnosis a little bit. I think if you have something that looks really weird like that, I think you want to do traction testing under anesthesia. I think that’s probably gonna be how you sort this out. Yeah. All right. I’m gonna call it off there. Thank you to everyone who submitted questions, both live — I know we didn’t get to — there are another 17 that are unanswered here live. And we have another 40 questions that were submitted in advance. I will record answers to those other 40 that were submitted with registrations, and we’ll get those out to you. Everyone, have a good day. And I appreciate your enthusiasm. And it’s been a pleasure talking to people from everywhere in the world. Fantastic. Take care.

Last Updated: June 6, 2023

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