 So we're going to talk a little bit about surgical technique, how to plan things, a little bit about what we do options for anesthesia for eye muscle surgery, touch on Botox, and a little bit about complications because as much as we like to think that our interventions never cause any problems, at times they do, anticipating them is good, dealing with them is better, and types of surgical procedures, weakening procedures, basically there's a whole bunch, depending on the muscle that you're dealing with, there are a lot of options. Recession, myotomy, myectomy, recession with anteriorization, mainly the inferior oblique, tenotomies, tenectomies refer mainly to the superior oblique, and a denervation, extirpation, that's a procedure done to the inferior oblique for people who cannot do recessions effectively and do horrible things to the muscle, and you'll probably not see anybody here do that but you'll read about it. And posterior fixation sutures where we're trying to differentially affect the function of a muscle at near, and not have as much effect at distance, or increase the recruitment of the contralateral muscle, an example of someone who's had an injured inferior rectus muscle after trauma, and we do a posterior fixation suture on the contralateral inferior rectus, remember with Herring's law you get equal innervation of both muscles, so you make it harder for my left inferior rectus to go down by putting a posterior fixation suture in, you pull the right eye down farther, expand the range where the patient can go into down gaze and keep single vision. And so let's try this, oh it works. Then strengthening procedures, resection, usually for horizontal muscles, occasionally for vertical muscles, advancement usually for a previously recessed muscle, and then tuck, which traditionally was just isolated to the superior bleak tendon where you fold it over on itself and sew it to shorten it, and a superior bleak palsy where you have tendon laxity, also has been popularized recently for horizontal muscles to use in place of a resection. The advantage is being that you're not cutting the anterior vessels, unless you encircle them with suture, and you decrease the risk of anterior segment ischemia. You will see some of those done in your time with us here in pediatric ophthalmology service. Now as far as special procedures, you'll notice in almost all of the adults that I do, one muscle is left on an adjustable suture. That allows us to anticipate variations in response to a given dose of surgery, adjustment usually being done, awake in the treatment room within a day or two of surgery, sometimes in patients who are very anxious, who can't sit still up to a week out, asleep again in the operating room, transposition where we're trying to use functional muscles to increase movement of the eye or change position, usually in the face of cranial nerve palsy, most commonly sixth nerve palsy, vertical shifts where we can take both horizontal muscles, rotate them up or rotate them down to change the vertical position of the eye. Kind of a handy thing to do to minimize the amount of, or the number of muscles that you're operating on. Now anesthesia, generally anesthesia is the most commonly used mode of, you know, making it safe and comfortable for us to operate on children. In adults, you have the option of doing retro-ball bar blocks. You can do most eye muscle procedures with the retro-ball bar. What that does do, on the other hand, is it limits you to one eye. And you'll find that when you're on service with me, most, if not all of the patients that we do, even on adults, I do under general, because a lot of the patients I do either have trauma, thyroid disease, or they're re-operations. And those folks, in terms of planning things, I want to be able to check for instructions, deal with scarring from previous surgery, and finesse things in the operating room to get the best outcome from the patient. On the other hand, I can tell you that when I operate, you know, it was a month ago in Nepal operating, and every single case we did was done with a retro-ball bar block with no nurse anesthetist or anybody else in attendance. Why? Because they didn't think we deserved one. The cases, by and large, went pretty well. Most of the patients are pretty stoic, and none of them got versed. You can do muscle surgery under topical anesthesia. I have done that usually with some sedation, and that's, you know, where you have patients who don't, you know, have some reaction to local anesthetics and have really high-risk airways in terms of sedation and general anesthesia. As far as injecting local, often if you inject subconjunctivally, it distorts tissues enough, it's really hard to make sense of things, but I've also done that in patients, again, where anesthesia was not safe due to general medical problems. At times you want to be careful with that issue with general medical problems, because when you try to save a very fragile patient from the harm of general anesthesia, if they're really anxious, often the trouble you cause with the anxiety can be just as bad as the general anesthesia. Now, when we're trying to operate, you want to have goals in mind. And what I mean by, if you take a child who's got infantile esotropia, you are not going to have normal binocularity almost all the time, so if that's your goal, you've got a goal you can't achieve. What you want in that patient to have eyes that are straight, give or take a little bit to give them the best chance of binocularity, but you're not going to change, you know, the underlying substrate in terms of their visual system and what it can accomplish. Generally, we want to try to establish competence, meaning that things are fairly well aligned in all positions of gaze. You want visual acuity to be equal, and often that's more important than getting the eyes lined up. Get rid of torsion if torsion is an issue. If torsion is present when you measure it, but it isn't an issue from the patient's perspective, dealing with it can actually create problems. If you decide to do a big tuck on a superior bleak muscle, which is probably going to change the torsional position of the eye, and the patient didn't have any subjective torsion, they're not aware that the other image is tilted after surgery. They're going to be tilted and they're not going to like it, and then you send them, and I spent, again, I've had patients where we've done several operations trying to get rid of unwanted torsion, where somebody didn't think about that after, you know, prior to the surgery. The other issue are surgeon-specific issues. If you know that you've never done a superior bleak tuck, trying to do one for the first time on a multiple re-op who's had a bunch of surgery elsewhere is probably not a smart thing. The other thing to consider is after you've done a bunch of surgery, you'll find that looking at numbers and tables, what you get may not jive with that. You may find you get more or less. There is a lot of variation once you start doing eye muscle surgery in how sutures are placed, where you measure from, and all those things that can make a difference and make those tables not directly applicable so that you need to look at your own outcomes and adjust accordingly. Now, one of the things I always like to do is think about things from the standpoint of what's in it for the patient. How am I going to change their situation? Is this going to improve their life? Are we going to get rid of double vision? Are we going to make it so they can function effectively in school or work without being picked on or having somebody say are you looking at me or are you looking over my shoulder? Are we going to increase their chance of having normal binocularity? Are we going to decrease risk of amblyopia? And then there are mitigating factors. The child who's got severe neurodevelopmental problems, who's got large anglo-exotropia, straightening their eyes is probably not going to change their ability to interact with the world, their ability to interact with other people and may simply amount to picking on them at which point it's our job to say this isn't a smart thing to do even though the physical therapist thought it was going to change the world and allow them to do everything and make this child normal. It isn't going to happen and sometimes you just have to come out and say that. In the face of any neurologic disease, seizure disorders, I've got spina bifida or severe developmental delay after a hypoxic insulted birth, we vary the dose of surgery that we do for esotropia. Why? Because we get a lot more mileage out of it. If we do the appropriate amount of surgery for 50 diopters of esotropia in a child who's got a severe neurologic insult, you may wind up with 50 diopters of exotropia. So it isn't that our goal is different, it isn't that we don't want to get their eyes straight, but we may have to tailor what we're doing to get a better outcome. And then the other thing to think about is in the face of biomechanical factors in the orbit, are they proptotic? Are they enothalmic? Because they've had volume loss after an orbital injury and they've lost fat. The procedure you do can change the fore-aft position of the eye and make things look better or make it look very unusual. Anytime you do a resection, the eye is going to move back a bit so ptosis will be accentuated. By the same token, if you do a huge recession in a patient who's got thyroid disease and the eye comes forward, that can accentuate the ptosis they already have can actually cause corneal exposure problems. I'm not saying you shouldn't do that, but I think you need to be aware of it and sometimes we need to let the patient know. If you're going to do something that the patient may not appreciate and you tell them that it may happen ahead of time, you're smart and if they discover or their neighbor points it out to them, they don't think you're so smart. Now, what about this cosmetic versus correction of deformity issue? I have a lot of patients that come in and they have their child who's not got very good vision in an eye due to some problem inside the eye and we're trying to make the eye look straight so the kid looks as normal as possible. That is not cosmetic. Cosmetic is when you take something that looks fine or you know, and somebody wants it to look prettier because they think it's better. Correction of deformity is when you take something that is not the way that it is supposed to be and you make it look more like it's supposed to be so an individual can function more effectively in society and most of the things we do with straightening eyes out fall in that realm. The idea being that there's very good data if you look into the data on the psychosocial aspects of strabismus, strabismus correction and the effects of having strabismus on selecting playmates, on hiring people. My colleagues, David Coates, Neville and Pacey and Baylor took photographs of kids and adults and digitally altered them to give them strabismus and then they showed the kids pictures to other kids and saying, which kid do you want to play with? And with the adults, they showed them to human resources professionals who should know better. And it turned out that the kids selected the kids with straight eyes to play with and the human resources professionals wanted to offer jobs to the folks with straight eyes. So we do make it so these folks can function better. Now, what do we do in the operating room? We talk about planning things and having things ready to have a higher likelihood of having a good outcome. COVID-19 is the only thing that's been shown in any ophthalmic procedure that will really affect the number of species in colony forming units and decrease risk of post-operative infection. Question of intracameral antibiotics and I think there probably is good evidence for that but as far as prior to surgery, a drop of betadine in the eye and that work was done actually by a pediatric ophthalmologist, a guy named Sherwin Eisenberg in Los Angeles working with patients in Kenya who published information about that and kind of got everybody going in that direction. The traction sutures, I think the traction sutures are very helpful to get good exposure to allow you to do a better job. There are some of my colleagues who think the traction sutures are kind of like training wheels on a bicycle and I don't share that viewpoint. I'd urge you to use them. You want to plan an effective congenital incision. You want to think about where you want to sit, where you want your assistant to sit and how you want to organize things have good lighting, good magnification. I would urge you to use loops. Many of the individuals I work with in developing countries and I do that several times a year do strabismus surgery with a microscope. They do it because they're all doing cataract surgery and it's easy for them to just use the same microscope, have them bring the patient in and do eye muscle surgery. The problem with the microscope, I mean it works okay for horizontal surgery. When you start doing vertical muscles, when you start doing oblique muscles, the positioning with the microscope is very inflexible and it is difficult to get good visualization of the muscle and do an effective job. And so I have switched many of the people that I work with to using loops and headlights. Now, here we go. We're not going to belabor this. You can look up amounts of surgery to do in various procedures. And this is for esotropia. The A got left off by the way this thing got put together. But these are basically the numbers here on the left for Marshall Parks for increasing amounts of esotropia in the amount of medial rectus recession, lateral rectus recession you would do on one eye, or medial rectus recession you would do on each eye for esotropia. And my mentor Jean Halveston measured things from the limbis. These are the amounts for the kind of the small, medium, and large approach to life under a year of age and over a year of age. And some of those numbers may look familiar. I use a lot of that information still today and I think it works darn well. For intermittent exotropia, again, you can look these things up, but ultimately you will arrive at your own numbers. I would imagine for most of you that have worked with me in the operating room, you've probably never seen me pull a table out and look at it in the OR. I did that for probably the first 10 years I was in practice. And I didn't even know where the table that I put together, I had a little chart that had all these things on it in case I wanted to refer to it. And now, you know, you reach a point where you know what you want to do in a certain situation and how to factor in the fudge factors. And this, again, another, this is Dr. Parks' approach to intermittent exotropia. These refer to bilateral lateral rectus recessions. And we'll just go back. How do we go back? Previous? There isn't a way to do this with this mouse otherwise. Now, if you're doing a patient who's got severe vision loss, we've got a large optic nerve coloboma or optic nerve hypoplasia and finger counting vision. We do larger, look at these numbers, they're much larger, larger amounts of surgery. You also do that in the 40-year-old who comes in, who grew up with large angel exotropia and has never had surgery. So that long duration and poor vision will change things as well. And then there are A and V patterns. A and V patterns, when we talk about patterns for business, we're talking about a disparity in the amount of horizontal deviation between up and down gaze. And basically, for those, you can, if there is inferior oblique or supere oblique overaction, weaken the corresponding oblique muscle to collapse the pattern. And we'll talk about shifting the horizontal muscles if there isn't oblique overaction. For vertical surgery, if you weaken the supere oblique muscles, you're going to change the vertical position by somewhere in the 10 to 15 prism diameter range. If you do a tuck, you're going to affect it by about 15, but you may get up to 25 prism diameters of correction, it depends on how much of a tuck you do. The way tucks are done, it isn't a matter of looking in a table saying, I have this much deviation and I'm going to tuck the muscle this much. It is more based on feel of the tension in the muscle because the tendons will vary as far as how much laxity is there and if you do too much, you'll limit movement of the eye. With the inferior oblique, again, you can plan on getting about 10 to 15 prism diameters of vertical change in primary position and will vary with the supererectus and inferior rectus with recessions of getting, you know, about two and a half millimeters will get you about eight prism diapers of correction and the most you want to recess the superior or inferior rectus muscle is about five millimeters with the exception of severe trauma, scarring, thyroid disease, all of which, in those situations, I think those of you who have operated with me will see us do, at times, huge recessions. You have to do what the patient needs. Those situations can be very complex and you probably need somebody who's been there before with you to do them. And then, again, we can go through, I'm not going to belabor the tables and nobody's going to ask you when you take OCAPs to recite somebody's table, but they more likely would ask you what would be a reasonable procedure for this patient and the problem they have to see if you can think your way through what needs to be done. Now, complications from surgical procedures, alignment issues are the most common. You know, what I tell patients when we're going to do a first time strabismus surgery is that we've got across the board somewhere in the 80 to 90 percent range chance of getting alignment to be acceptable, give or take a little range where we're happy with things, about a 10 to 20 percent chance that they will need additional surgery. That means if I'm doing, you know, 10 patients on Monday at Moran that I could expect that one or two of them were going to need to have additional surgery at some point. So I always tell them that alignment issues which may result in diplopia, those are things that go with the territory that may happen. The things that we usually do not see are perforation sclerosis, serious infections and things of that sort. And we don't want to see serious scarring, congenitival cysts, suture granulomas happen. People at times react to vicaral, realize that all of the absorbable sutures that we use absorb because they incite a local inflammatory reaction. If that is an intense reaction and somebody's got a very active immune system, you can have a granuloma result simply from the inflammation that usually will go away. Sometimes you do need to excise them. Now, what about refractive error change? If you do a large resection on a muscle, you can induce a fair amount of cylinder. It is usually temporary, so you want to avoid making huge changes in the patient's glasses in the first couple of months after surgery. But you want to be careful with that and think about it in a child who is not seeing as well after surgery. Let's say we're in the operating room together and I'm having you do your first scleral pass with a muscle and you feel a big pop. And I kind of go, and we pull that out and there's a kind of a little dot, a clear liquidy stuff coming up through the hole. What do we do? What's going on? Where did that needle go? It went into the vitreous. The stuff coming out through the hole is vitreous. And so the question is, what do you do? And knowing and having a plan ahead of time is always better than making it up on the spot. And if you really don't know what to do, call somebody else who does know what to do. But in this circumstance, it isn't that uncommon for people to wind up in the suprachoroidal space, but going through, if you've got vitreous, if you've gone through choroid, you've gone through retina, you're in the vitreous and there is a communication that will first of all allow things to get inside the eye, but more importantly, allow liquid vitreous to get under the retina and cause a regmetage of retinal detachment, which the patient won't be grateful for and your retina colleagues won't be grateful for. So the thing to do is to stop operating, dilate the pupils, take a look in the back and deal with the issue. And, you know, lasering around the break in the retina, which is basically what you've created, is an appropriate way to deal with it and then go ahead with the muscle surgery. I, in the past, before the days of laser, when there wasn't an indirect laser, believe it or not, once upon a time, we used the cryoprobe and you would gently cry out if you're going to use the cryoprobe, be cautious, you're nervous, you really want that fixed and everybody's tendency is to do too much cryo, at which point you can actually cause, you know, traction on the retina and further problems, but that's something that you need to have a plan for particularly in patients who've had trauma, patients who were highly myopic within sclera, that would include a fair number of the patients that I operate on after they've had a sclera or buckled placed, maybe removed and they were highly myopic to start with, they got perforated a couple of times during their sclera or buckled placement and then I'm trying to do muscle surgery and it can be very, very challenging. Infections, any time we've done eye muscle surgery and you get a post-operative infection, in my mind, that is always orbital cellulitis. When we talk about preceptile cellulitis, you're talking about infection in front of the orbital septum, any time we've opened the intermuscular membrane, you've got access to whatever process is going on posteriorly. The other place you want to think about access, where were my sutures? Was any of those, were one of those sutures deep? You know, do I have endothelitis? We've lost one eye here, one of my colleagues had a problem with a patient where they didn't recognize that the patient was infected, didn't recognize the patient had scleritis and subsequently did not recognize that the patient had endothelitis and an eye was lost. So you want to be thinking about, you know, one of the things I go through in my mind, and I do that when you guys call me with a problem with a patient, is what's the worst thing that could be going on here that I could miss and really screw things up? And I think that we're dealing with complications after surgery that you've done. I'd urge you to think in similar means. Other things that we see at times, fat adherence. Staying out of the fat, you'll hear me when we're operating on the medial rectus telling you to stay right over the muscle. The reason we do that is to stay out of the medial orbital fat pad because if you're in that medial orbital fat pad, fat sticks to everything. It is the vitreous of eye muscle surgery. We don't want to encounter it. And once you get into the fat, I may never be able to fix the scarring that results. The other issue is dealing with conjunctiva. And I know that my retina colleagues like to use the Q-tip and push things every which way. And at times, I mean, because they have to expose a whole bunch of, you know, landscape to get things done. But if you treat conjunctiva delicately, gently, don't cause undue trauma to it, things will heal better and you'll have less restriction. You may also, in planning surgery, want to think about whether you want to actually bring conjunctiva back to the limbis. If before surgery, things were very tight with four-structions and an eye has been esotropic for years and years and years, once you get the eye straight, if you bring conjunctiva right back up to the limbis, the conjunctiva alone may pull the eye back in so you may have to recess it. Another thing to put on your list of things to wonder about and then change is an eyelid position. The most common there would be with inferior rectus recession because the lower eyelid retractors sit right next to the inferior rectus. That is the reason we try to free up those attachments, you know, from Lockwood's ligament. No matter how much you free those up, to some extent, if you do an effective and a fairly large inferior rectus recession, the lower eyelid is going to drop a bit. So I always warn patients about that. When we do thyroid patients here, the order in which things are done are orbital surgery first, muscle surgery second, and lid surgery third. And that way if I need Dr. Patel or Dr. Crumb to go in, put a spacer in the lower eyelid and bring the lower lid back up, they do that after I've done the large inferior rectus recession. And then slipped or lost muscles. Slipped muscle basically refers to a muscle that has moved back within its sheath. So it may be that sutures were put in very superficially and the sheath of the muscle is still attached, but the muscle has moved back in it. Another variation of that is the eye where the muscle has moved back and there is scar tissue attached to the muscle, making it look like it's attached where you wanted to put it. That is called slipped scar or stretched scar, a woman named Irene Ludwig kind of popularized that terminology. Lost muscles, the muscle has become detached from the globe and has disappeared somewhere back in the orbit. And when I was a resident, somebody talked about this and I said, well, wait a minute. I mean, it's somewhere there. I mean, you got this eye socket that's sitting here. It didn't go out the back of the patient's head or out their left ear. It's in there. I mean, it isn't lost. You know where it is. And I didn't have a clue how difficult it is to find it. If you wind up in a situation where you think a muscle, you've cut on the wrong side of the sutures in a resection and suddenly the muscle just disappears, please don't dig around excessively. Call somebody like me to come help you find it right there in the operating room. Because that is absolutely the best time to find it. There are simple things I can talk into doing over the telephone that I have talked a number of my colleagues here into doing that will likely let you find it. Tip what that involves is locating, the muscle will never be right along the globe. It will be, it goes back through its particular the medial rectus muscle, which is the most commonly lost muscle, through its sleeve and tenons layer. And you find that by looking for where it's bleeding. You follow it. You put a forcep through there gently, open it, grab it and pull out. And it's like pulling a rabbit out of a hat, but often that muscle will come back out of there. You can put it back where it belongs. Everybody's happy. The worst thing in the world you can do is have somebody dig around in the fat. Because once somebody has been going all over the place with a pair of scissors frantically trying to fry in the muscle, I'm not going to be able to find it. There are ways of going in with the ENT surgeons taking out the medial orbital wall, locating the muscle posteriorly, putting suture in it, threading it anteriorly along the medial orbital wall. Those are GWIS procedures. They never result in normal motility. I mean, they're, you know, people are really impressed when they can put it back together, but it's not a good thing. Now, bradycardia, oculocardiac reflex. In the literature, it'll tell you that the medial rectus muscle is the most common muscle involved. That's only because it's the most common muscle operated. Where you want to think about cause and harm is in somebody who's got a very fragile cardiovascular system. They've already had an MI or a stroke, and they're not going to deal with severe bradycardia or hypotension for a long period of time. And where I've seen the most trouble personally have been in young, healthy adults operating on vertical rectus muscles. Almost every patient that I've personally had prolonged episodes of acystole in the operating room where the anesthesiologist has jumped out of their chair saying, what are you doing? And there's just a blank screen. Has been a young, you know, like teenage or 20 year old, in the 20s person where we're pulling on the superior rectus muscle. So think about that when you're doing that, and basically if you back off on it, you let go of the muscle. Their heart rate will come up. They can give them something to compensate for it. Why would I mention this? My other purpose in mentioning this is if you're going to do adjustable sutures, you pull on the muscle, and you're doing it in your office, in clinic. You need to have a plan to deal with a patient who suddenly has a heart rate and blood pressure of zero. And particularly with the office chairs that don't lie flat, all the blood pools in their hips, in their pelvis, and you have to get them out of the chair and put them on the floor to get them to come back. That's the reason, if you look in pediatric ophthalmology clinic, all of our chairs there lie flat, and I did that purposely so that if one of my colleagues wanted to do an adjustment there, they can do it. I think you need to think about that whenever you're doing procedures, because of the chance of eliciting an ocular cardiac reflex in clinic. I do all my adjustments in the procedure room at the Moran OR so that there are anesthesia and nursing personnel around to help take care of things if bad things happen because I've gotten burned before. Who here has seen a case of MH? Anybody been involved in it? I think by the time I was, as a second-year resident, I had a kid develop full-blown MH doing muscle surgery. It didn't have a good outcome because dantraline, the medicine that they used to deal with it, they allowed hospitals in Michigan then to share the supply, and it was at the other hospital. Every patient we do at primary, there is a sheet in the patient's chart that has all the medication doses based on their age and weight for resuscitation and for MH. They have an MH cart. They do the same thing here in the OR. I want you to be aware of it. You may be asked to kind of put your I'm a regular doctor hat back on and help resuscitate a kid if you have an opportunity to go through and keep ACLS current keep PALS current if you haven't taken PALS and you want to do it when you're on our service we can try to make arrangements to do that. I would urge you to do that so that you can help anesthesia resuscitate your patients. It may save a life. What about Botox? Botox is botulinum atoxin was developed by an ophthalmologist, a guy named Alan Scott at Smith Kettlewell, San Francisco. I was one of the investigators that worked with a bunch of other people and a bunch of other people trying to find useful applications for it. We used it both for blood for spasm and for strabismus early on. That would be in the mid-80s. It prevents release of acetylcholine. It is fragile. The fact that it's bound to tissue 30 minutes after injection is significant because when we inject it into eye muscles we position the patient so that if it leaks from where we inject it the tissue that it becomes bound to is likely tissue that we would like it to be bound to and not something else, particularly the levator, so you don't wind up with complete ptosis, particularly in a child. The maximal effect occurs about three to seven days out from an injection. Wears off about two to three months out and I still occasionally do eye muscle injections but for most people doing strabismus work on a general basis unless you're in the UK where you can't get access to the operating room, Botox is not in general use. Subacute, meaning I'm not getting better as quickly as we'd like, paralytics for business, almost exclusively six nerve policies where we inject the ipsilateral medial rectus muscle to prevent contracture is still useful for some patients. There's small-angle horizontal deviations and overcorrections and undercorrections almost no one is doing this anymore. I've not seen anybody try to use it in graze disease in years. The first paper published on acquired nystagmus in an adult using Botox. Gene Helveston, I think my name wasn't on the paper, I did the work but my name isn't on the paper. Gene and I think one of the residents in Indiana, their name is on it. What we did was to take 25 units of Botox which is 10 times the dose that we use in a medial rectus muscle and injected it retro bulbar to see if we could keep an eye still in a patient with acquired disabling nystagmus and indeed it kept the patient's eye still. So in that series of N of 1 it appeared to work my roles I got called urgently to an examiner saying, do you know how to do a retro bulbar injection? And I said, sure, give me that and that was that because Dr. Helveston had not done a retro bulbar in years and could not remember how to. And it, again, the situation where you're going to use that with nystagmus is it has to be a patient where you're trying to make it so they can sit still and watch television. There isn't somebody who's going to be binocular who's going to drive, who's going to walk around. That eye is going to sit still but their other eye is still doing all kinds of things so they're going to have to patch the other eye. You've made them a one-eyed patient who's going to have to target their eye wherever they want to look and that is a big discussion to have before you do that. It is helpful to those patients where their nystagmus is so overwhelming their suicidal when they come in the office often. That is a big problem. Now let's go to and see if I can get this other thing to let's see, this we close, right? And then we go back to this. How do I get rid of this thing? There we go. Has anybody here been involved seen a Botox injection? Other than for blepharospasm? I mean, blepharospasm are simple. When we were doing them in the study, I did a bunch of blepharospasm injections but they're boring. I didn't really find the blepharospasm patients to be folks I like to hang out with so I stopped doing them. I also was of the opinion I think someone quoted me that you could teach a chimpanzee to do the injections. I mean, they're very simple and you just do these injections and it's not what I want to do. Now we're going to go through some patients this is where we get the audience participation time to wake up and see if your coffee worked. This patient, the first patient is a nine month old who has been esotropic according to parents since birth and when they look they have equal fixation they'll look equally with either eye and their deductions and versions are full they've got a normal anterior segment a normal fundus and they've got minimal refractive air and this is their motility assessment. When you're looking at this thing right here, this is primary position up gaze, down gaze, right gaze, left gaze measurements. We don't have the oblique measurements for this kid very difficult to get those in a small infant. What does this child have? Give me a diagnosis. How about a differential diagnosis? Child's esotropic, nine months old don't have significant refractive air this would be a very typical OCAP question. Make it multiple choice. Do we is this spasmus nutans accommodative esotropia bilateral six nerve palsy or congenital esotropia. And this is kind of a quintessential congenital esotropia patient. Now this patient if we go back and let's go back to that first patient, the next thing I want you to do with that let's see go back to the previous here come on mouse. Somebody come up with a plan I want to hear maybe three different plans, two different plans that are reasonable with this patient having equal vision. Let's say for a first surgery what would be the most reasonable thing to do. Absolutely and now let's say we'd already done that and this was the patient's measurements. What would the second procedure be? Absolutely very good. Now we're going to change things up a little bit with this next one. Notice the difference here is that now we're 20 ET in up gaze we're 50 ET in down gaze. So this is a V pattern my eyes are more in when I'm down they're less in when I'm up that's where the letter V description comes from and this patient if we're doing initial surgery do we need to take this into account if you know in planning our surgery well if we want to get rid of that disparity between up and down in addition to straightening things out yes and in this patient and there is no oblique overaction here we're going to shift the muscles vertically in addition to recessing them doing that bilateral medial rectus with a V pattern we always shift the medial rectus muscles towards the apex of the pattern whether it's V or A and we always shift the laterals towards the open end you can take that to the bank that always works now how much you shift them is it a half or a full tendon width depends on the amount of disparity there's not general agreement on that that's one of those things that you're going to have to figure out or I can guide John if you're going to do it for the first time call me and we'll chat about it so now we're going to move on this is a similar patient notice that the difference between up and down very similar but now we've got right hyper and left gaze left hyper and right gaze and we got 2 plus infir oblique overaction so where we've got infir oblique overaction and a V pattern it turns out that infir oblique overaction commonly goes along with V patterns why because remember one of the functions of the infir oblique is abduction and in its field of gaze which is up gaze you're going to get some abduction which causes there to be less estropia with the infir oblique overaction to collapse the disparity between up and down gaze there we're going to weaken the infir oblique muscles in addition to doing horizontal surgery for the primary position deviation so put that together and give me a procedure please of both eyes absolutely that makes sense if not I mean say something because it needs to make sense and now this is a different situation this is a patient who's got constant leftisotropy patient's got optic nerve hypoplasia that's not going to get better they're not going to have normal vision in that eye patient has 45 prism diopters of esotropia at distance and near this is a little bit of a trick question and the parents they're kind of ambivalent about doing something but grandma is there and she's looking at you saying I want this fixed I want this fixed now I don't like the way that eye looks what procedure do you do paid attention on the service that's good no that's absolutely right your strong obligation at that point is to tell the parents that operating on that child at that particular moment time at nine months of age is absolutely totally ridiculous and you shouldn't do it and grandma needs to get her act together and quit being a problem and the idea at times is that grandma's devastated that her grandchild has his crossed eye on the side doesn't see and every time she sees the eye crossed it bothers her that's why she wants you have to understand why she wants it fixed I'm not trying to take on grandmoms in general but the bottom line is that if going back to the what's in it for the patient this patient isn't going to see any better out of that eye and at nine months of age their sense of self their self-esteem isn't going to come from anybody grandma being worried about that eye crossing and it isn't affecting their ability to interact with other kids so we follow the child and prior to starting school you want to make that eye look straight and that's the time to do that somewhere between three and five and then you straighten out and if we're doing that now we're let's say we're four years old they're back you put safety glasses on them to protect the the right eye from from injury and they still got about 45 to 50 prism doctors vastropia what surgical procedure would you do right who would do surgery on the right eye nobody yeah and not me either and what you may see with this kid is this kid may actually have some nystagmus bilaterally and you may find that they've got a little bit of a face turn and this right eye they prefer to keep it in adduction I'm still not going to recess that right medial which would tend to move that null point that they've developed closer to straight ahead but operating on that child's only seeing eye you really have to be pushed to do that and and that's a frank discussion to have with the parents you say I'm not going to you know likely to have a little bit of a face turn still we're going to make the eyes look nice and straight but the other thing you have to tell them is the thing that keeps those eyes looking straight is seeing a lot of each eye and using the eyes together and they're not going to do that so that I may drift but it's important because they probably have a neighbor who's told them that somebody said you have one chance to get it right it has to be done by age six and after that you're toast that's a kind of a common thing for neighbors to tell people and I'm trying to be helpful and the parents are terrified and so you say you know if this drifts at any age you do more surgery and make it look better and that's a good thing for them to take home and understand about that so that they're not terrified now shifting gears we've got this three year old who comes in and about four months ago they started crossing and they finally decided yeah it's really there they want to come in and have it looked at and the exam they've got equal fixation behavior they've got about 40 prism diapers of esotropia but it varies a little bit and you've got this cycloplegic refraction what's the patient have what's the diagnosis accommodate of esotropia meaning as they focused to overcome the hyperopia their eyes cross that's different than the normal situation I mean this is not this is at the upper end of what we had accepted in a child for the amount of hyperopia but most kids with five diapers of hyperopia focus and keep their eyes straight kids with the cognitive esotropia cross when they do that and so is the right thing to take this child to the operating room and straighten them out not unless you've got a boat payment do you know and unfortunately I see that happen it's very disturbing but the right thing to do that lets you sleep at night and feel good about what you're doing and feel you're doing a good job taking care of patients is to put the child in glasses you put them in that full psychoplegic refraction and so we see them back in two or three months their eyes look nice and straight with the glasses on do we operate at that point no we say you're doing great you know come back and see me in four to six months or something and follow them along as long as you've got their eyes straight they're going to do fine now this is the same patient but instead of looking straight they come back and they've got 25 prism doctors of ET in primary it's equal and up and down gaze it's also the same at near what do we do here make sure the glasses are right so you check the psychoplegic refraction that is an excellent idea I like that and the glasses are right so what's your next move okay and they say gee my neighbor said they patched their child's eye and it's straightened out why aren't we doing that well because patching doesn't straighten eyes we use patching to treat amblyopia we do not use it to straighten eyes it doesn't straighten eyes and so this patient needs surgery now do we do surgery for that full you know large amount of estropia or do we do surgery for this amount of estropia what are we trying to correct the 25 prism doctors so that with the glasses on the child's eyes are straight that will result in the most stable alignment that will give them the best chance of developing normal binocularity now this patient shows up and they've got estropia since birth and they just their pediatrician told them it would go away they saw somebody at Walmart that told them it would go away and they show up in your office 20-30 acute edgi they've got no significant refractive error they've got this and they've got dvd 3 plus it's really noticeable sometimes one eye sometimes the other eye and the question is what to do and there are kind of two issues here one is the estropia the other is the dvd dissociated vertical deviation so for the estropia what would be the most and this is equal at near as well 45 prism doctors what procedure would help the horizontal misalignment absolutely now and in both eyes get things straight and then the the issue is what do we do for the dissociated vertical deviation and we separate our thinking like the issue of A and V patterns with and without inferior bleak overaction if you have dvd and you've got inferior bleak overaction you're gonna have to do something with the inferior bleak to get it fixed and the most common procedure done is an anti-replacement procedure where we instead of simply recessing it reattach it further forward on the globe where you change the inferior bleak from an elevator to a depressor popularized by a guy named Jim Mims who's a pediatric ophthalmologist in San Antonio, Texas and since written about by a whole bunch of people but the idea is that that in that circumstance as long as you don't do too much is a good thing if you do too much you will actually, if you're doing it asymmetrically limit upward movement of the eye because of restriction and then you'll wind up with a secondary deviation the other eye way up here and that becomes a big problem trying to fix and in inferior bleak overaction now what about if we have no inferior bleak overaction what would be the procedure of choice there and this again is a fair game OCAP kind of question so worth knowing about the most reasonable thing done in that circumstance is superior rectus recession okay the third line thing done by some people self not included is inferior rectus resection and some people will advocate that I have never found a patient combination of either dealing with the inferior bleak or superior rectus with DVD that I was not able to fix which is why I have not gone ahead and done that I think that now with the superior rectus again it's easy to say that if you're going to try to do it and you've never seen the superior rectus except you know when you're a resident doing things don't do that for the first time your first week in practice call me we'll talk through it because it's a quick way to get yourself in big trouble because you have to pay attention between the relationships between the superior rectus and the superior bleak and deal with all those issues to do it effectively you always want to hang the superior rectus back so that you're not putting inadvertently suture through the superior bleak tendon which can be difficult to find if you've ever looked for it it can be quite a challenge but it's a very effective procedure and but that's an easy one to kind of talk through but without inferior bleak overaction superior rectus recession with inferior bleak overaction you do the inferior bleaks the question is well do I do both eyes or one eye let's say it's just one eye to see the parent see going up if you see any DVD on the other eye you have to do bilateral surgery even if it's not apparent to the parents because if not two weeks after surgery they're going to call you saying doctor the other eye is going up now and you're going to be going back to the operating room to fix the other eye so you want to look carefully for that and I'll often recheck them if I'm planning on doing unilateral surgery for DVD the day of surgery and tell the parents I'm ahead of time that I'm going to check it and I may ask them to let me do both eyes right then and there if I see any because I don't like to be surprised with that stuff and then we've got one more we'll look at and then we'll kind of wander on so this is a patient who's been five year old and the parents tell you that they see the eyes turn out mainly when the kids sick mainly at the end of the day if you ask for a percentage they say 25% of the time and kids got good vision and when you break the child down you're seeing about 30 prison doctors of intermittent dexatropia and it's comatant up down right left and when I say fusion abilities are estimated as good what I'm talking about is that when I stop covering I look to see how quickly the child pulls things back together and if they pull things right back together that's good if they wait 5-10 seconds they pull things back together that's in the fair range and if they just sit there that'd be what you'd call poor and so in this patient who's turning out 25% of the time are we going to operate in this patient now? I'm not because the patient's probably straight 75% of the time that's assuming I agree with what the parents are telling me about 25% understanding that parents vary hugely in their ability as observers and one of your jobs as a parent is to get used to how your kids look now if that patient and we'll go back to this now is turning out 75% of the time let's come up with a reasonable procedure to do because at 75% of the time the child is at risk of losing vision in an eye developing amblyopia at risk of losing binocularity if you let them become constantly misaligned and we worry a lot anytime they're misaligned more than 50% of the time if we're going to do surgery here what would we do? lateral rectus precession bilaterally is probably exactly what I would do in the operating room let's say the child had had amblyopia in the left eye and we are now at 20-30 and 20-40 right and left would that change anything? yeah I'm assuming that 20-30-20-40 was the result of the patching let's say they started at 20-80 very good question again she's pinning me down in the details here the bottom line is yes you want to and that's an excellent question the idea is you deal with amblyopia first why? amblyopia basically having equal vision after you've done treatment or as close as you can get it will improve your chance of maintaining good alignment and reestablishing normal binocularity and so if they respond as expected amblyopia treatment and they'll do it now sometimes parents don't and you wind up operating anyway after you kind of get pushed into a corner but in that circumstance I am honest with the parents you know, yeah we're going to operate but we haven't done as good a job with the patching as I'd like we're kind of between a rock and a hard spot and the results of surgery are not going to be as predictable nor likely as long standing as if we'd actually done that you know and I try to lay things out so they know what's going on and if I'm worried about something I let them know about that so they know I'm worrying about it don't just say everything's going to be fine we'll get this fixed I can't tell you the number of patients I have we're talking about doing surgery that want to know what kind of guarantee comes on the procedure and I just say well the same one you came into this life with you know guarantees come on toaster ovens and microwaves not people in operations and all I can guarantee is I'll do my best to get your child fixed or to get your eyes straightened out and you know and be honest with them and that's where we are now what questions do y'all have about this otherwise get out here and have a good day