 That's well, nice to, it's exciting to lecture you guys. I really actually love teaching and it's one of the reasons I wanted to be an academic. The, this is, I think a topic that I used to dread as a resident, like being lectured to, it was just a guaranteed sleeper. The amount of Monday morning, it's like even worse. So the, but I've come to actually really enjoy a lot of this stuff as I've understood it better. And I think typically it's poorly explained. A lot of these tests, you know, it's for business and all this, you know, rep no correspondence and it's anomalous and all these things. So hopefully as we go through some of this, I think this is pediatric ophthalmology. A lot of it's not easily testable, but a lot of stuff is. So it's, I'm much more into clinical stuff than just teaching at OCAPs. But I think there's some, I use stuff on OCAP. So yeah, I won't be offended if I'll sleep. I am a notoriously fell asleep, but I'm also very lectured. I can't, I can't hold still and stay awake on one of these topics. So nonverbal pediatric eye exam, a lot of the stuff you gotta, so P's you split to all sorts of different things. The verbal child, this is a nonverbal child and how you approach them differently. So the kid who can tell you what, you know, what letters he could see in the eye chart is a big difference versus the kid who can't. So in a nonverbal patient, what are you looking, what are you trying to test? What can you test? Fix and follow, yeah. So it's a visual acuity, right? And you want to think big picture, what am I looking for? I'm actually doing the equivalent visual acuity. What other way can you test visual acuity at this age? Yeah, perfect. What's, now I don't know if anyone uses here, but if you guys heard of CSM, Central Study Maintained. So it's another way that you test visual acuity in kids. I'm just gonna say, I actually love pediatrics after I'm back up for a sec. I love pizza after all. I'm surprised why more people don't go into it, but there's obvious reasons that some people don't go into it. So we'll try to get, you know, try to, when you work with us, hopefully we'll get you to figure out how to test the iXM4 turned into this. But I'm a big fan of toys. They don't want to, they don't want to work with me. So generally visual acuity, the central, so CSM is something that people, I don't think this department uses it as much, but a lot of pediatric ophthalmology departments use CSM for visual acuity. And so we're gonna walk through what that means. So the first C, for the first letter C is central. Now, any guess what's central is testing? I thought it was just vanishingly fixed, like right in front of them. Yeah, yeah, good, Ashley. So it's not just fixing, but if they fix and their eye looks straight as they're fixing. So when would your eye not look straight but be fixing? Damn, nice. Sorry. I don't understand how you go capitol-like. I thought like recently. So that's not actually. So do you test centrally? Do you test centrally? When you do central, do you test it monocularly or binocularly? Any other, there you go. 50 chance. Quick, quick, quick guess. The voter's split. This was on, off the question last year. I remember seeing it. If you feel like this is something that's worthwhile. Because like, yeah. Why not do it monocularly? It's, it's flipped there. It's, so it's, this is monocular because if somebody has an ET, what's the eye that's, the eye that's deviated in, is that central? Technically no, but if you cover up a good eye, then you can really see if they have, you know, a line of sight. So, so, I hope this is a safe place to just guess and get it wrong and not feel stupid. Because I'd rather have you just guess and get it wrong than not say anything at all. I feel like I learned a lot more when I kind of put myself out there. So you can just read and check with the Cornell Reflects and make sure they're looking straight at you. You test it monocularly and you're looking for extra phobia of fixation or angle capa. And so we'll talk about that. Steady, what is, so let me just back up. So if it's, if they're not central, then the way you, you, charm this is you say you see or I'm central. So a kid could be CSM or UC, US, UM or any combination of those. So what's steady testing for? Any thoughts? What, when is an eye unsteady? Unsteady. Unsteady, yeah. This one's tested monocularly or binocularly? Was that correct? You said one and two, so binocularly. This last one is binocularly, so. That's good. No, no, no, I'm glad you're guessing, yeah. So, are you gonna pick up latent nystagmus if you're testing this, testing it this way? We said no. Hey, we're gonna put it like this, it's yes, but that was very confident, that's why I like it. The, so that's the reason you're testing it monocularly is you're gonna cover one eye and still see if it's, see if it's still steady. Cause what's the difference between latent nystagmus? This nystagmus is not always there. Nystagmus, yeah, only comes out with monocular testing. So it's, it's, it's, it's latent. So that's why it's important to do the test of monocularly. Maintain, anyone, anyone want to take a gander on this? I'm gonna make a guess the whole morning, so. Please, please keep, keep going, Dunn. Is there a new fixation with movement? With, with uncovering, how's that? Or was, so, so, yes, so if I'm looking at you with this eye, so maintain is the one that's binocularly tested. If I uncover this eye, is this, if I uncover the other eye, is that I still looking at you? Can you still keep the target central or can you do, I thought you kind of. You're not testing motility with this or reversions, reductions or anything. You're just seeing if, are they still holding an eye at you? So what would be a situation where you would have unmaintained, can anyone give me kind of a scenario? I'll give you a hint. If you're ortho, and I uncover your other eye, is there gonna be any shifting? No, so, so, what would be a situation where there would be shifting? Easy trip here, easy trip. Yeah, so you've got your business and then one other thing. So if I'm ET and this eye, this eye's covered, this eye's looking at you and I uncover, what's gonna make me wanna go switch to the other eye? And the other, yeah, if I've got an eye preference and the preference is to the other eye. Does that make sense? So all this talk about the fixing eye or the eye preference or maintenance, you're looking for amblyopia. You're looking for, they've got preference for one eye over the other. And then this, yeah, the reason you care about that is because amblyopia is extremely sensitive, both in terms of it's really sensitive to strabismus and amysocatropia and deprivation, but it's also really sensitive to patching. So the earlier you catch this, the earlier you intervene, the less deep the amblyopia will be and the faster the recovery will be. So we're talking about fixing eye preference and whether it's maintained. Again, we're just trying to see if we can find that. Fixed and following, I think it's nice because you still test it monocularly, you just move the patient. What sort of fixation targets do you think work the best in a nonverbal age range? Zero to two. And you guess what the first thing a child really sees and appreciates? Faces. Faces, yeah. So I just put a toy in my mouth and I move the toy with my teeth and make a bunch of sounds and then I just look at them and they just will fix it right on your face. And then, so what I do is I do fix and follow and then I look for the fixing eye and I do that by just covering and uncovering each eye seeing if there's a shift in which I essentially looks at me the most and then I look for this daggers and you're essentially doing the same thing as CSM but just in maybe having more straightforward. Wait, does that make sense? But hopefully CSM, I think you do get tested on that. So let's review late next daggers. MJ is demonstrating it with one-handed blow. That is perfect. So usually appears within the first few months of life for the first few months of life and it's a horizontal dirt misdiagnosis. Any guesses? This is another kind of hyalocathing and a great way to identify late misdiagnosis. Does the fast beak go away from the clutter or towards? Here's this one. Away, yeah. Nice. So the way to think about that is I just think it's always trying to get away from the clutter. It's trying to, you know, sneak out the other way. It will switch when you go to the other eye. It's the only misdiagnosis that has the fast beak that switches that in that manner. So you see a lot of misdiagnosis in kids who have this misdiagnosis complex like ET, DVD or fusion is compromised from an early age. We're gonna talk a lot about that later on. Usually poor serriopsis, again, because it comes in with, comes in with, so yeah, you usually see, again, like congenital ET, DVD, the eyes are just not very well aligned so they don't get good stereo. And it's gonna throw off monocular testing, why? So if you test a visual cue and you cover one eye at a time, why is it gonna screw up their testing? Yeah, you're gonna get misdiagnosis. It's gonna throw off the visual cue to you out. How is amblyopia treatment gonna be affected by late misdiagnosis? Why can't you pinch? They're just gonna have misdiagnosis. I mean, it's obvious, but yeah, exactly. So you don't have to think about this as you're seeing the kid and you see late misdiagnosis and then they find out that they have amblyopia. You've got to get creative in how you're gonna treat it, like foggy one lens with like just a strong prescription is gonna blur them more than they're amblyopia so they'll start looking through the other eye. But not enough to cause the late misdiagnosis. So a few times I'm gonna do these sides, like a whole lecture of misdiagnosis to me is like torture. So we're gonna do, so I'm gonna try to throw some pearls here the way to what we're talking about, but moving on to non-verbal eye exam, you do a lot of motility and alignment checking just like this car, right? That's what we're taught to be auto-mechanics. Nobody thought that was funny. Yeah, I thought it was like pounding me over over at the school. We're not mechanics, taking care of the whole person. So that was sarcastic. So alignment fixation is the key. We're gonna talk about that. And eye preference is also really important. So nice of you to question, how do you, we talked about maintain, how does, it's hard to tell which eye is the fixing eye in a child who's straight. How do you, how do you figure out eye preference in that child? Is there a way to do that? Prisons, I expand. Forebase up would be within our fusional virgins range. So you gotta, so if I put a forebase prism up in front of your eye, your eyes would actually make a readjustment to line it back up. So you're on the right track. You do like a, like anywhere from like a 15 to a 20. So you can tell the fixing eye in a kid who's not straight, right? So you make them, you make them not straight if they're worth it by putting a prism in front of their eye. I usually do like base down or base up and that splits the images and then you just look at which one they look at. So if I put a prism in front of this eye and so if it's a base down prism, the image is gonna appear up. So again, the eyes are both gonna look up when the prism is front of it. So I'm gonna walk you through this. I put a prism in front of the right eye and both their eyes, refix it up. I take the prism off, they go back down. I put the prism in front of the left eye and nothing happens. What's, what, what, what is that? How do you describe that? What's going on? Fixing with the right. Fixing with the right and probably have some envy over in the left eye because they never, that doesn't cause them to refix it. Does that make sense? So that's what you do with that test. It's called the induced tropia test. So it's a good name, it actually makes sense. So we're gonna talk about these strobismus prefixes and acronyms just briefly. You guys probably all know this stuff. Bob Hoffman, we saw a note that had all these acronyms on it and Bob said, oh, it reminds me of TMA. Does anyone know what TMA stands for? Too many acronyms. Yeah, it's like Bob, perfect Bob humor. Yeah, so ETXT, you're familiar with ET's crossed, XT's out. Does the hypertropian need laterality to it? How come the horizontal ones don't? True, it's because our eyes are on a horizontal plane. So that's the difference. Vertical ones is if your eyes are on a horizontal plane, you can't tell which one's up or down. Occasionally we do say laterality though for the ET's or the XT's. Why is that? Any guesses? It's a great name, yeah. It's clearly on one side in that case. Any other thoughts? I don't sometimes do that if it's the ambi over here. Yeah, okay, you're all sorry. If they have a clear eye preference, it's always the left eye that's turned on, yeah. So usually if you don't write left or right, it means that they probably have alternate fixation. So we're gonna run through this quickly. I want everyone to kind of speak up and just guess if you, I know we've got two people who've been through the P's rotation, which is a little disadvantage, but I want other people just to guess it as well. So parentheses, what does parentheses mean when you document that? Any guesses? Intermittent. What, is it okay if I say it? Yeah, yeah, there's a few seconds, but it's okay to let it linger just a little bit, you know? No, no, no, I want you to keep guessing. The, so if there's intermittent, are they able to fuse? Yes, yes, whoops, posthumous accepted near, later on we already talked about. And then if there's no T, what does that mean? If it's just E, yeah, good job, Chris. So you only see it when fusion is disrupted. So let's talk about some testing that we do with the occluder. You guys, I've seen on the Oplo exam in Epic, do you know, I'm sure you all know Black Thing is an occluder that gets you to the alignment exam. It's like so small and it's pixelated and it's hard to tell, I don't know what that was for a while. It's supposed to be actually one of these. So there's three kind of main tests that we do, and I want to jump to Mr. Bismuth Simulator. So this was done by a guy named Farooq Ornate who trained at Indiana where I trained in pediatrics and ophthalmology. He works in, to know how I can reference it, Ohio State, but the, I think it's pretty helpful and at least to explain some of these basic things and how the occluder testing works. How's everybody's weekend, by the way? Who's called busy this weekend? Yeah, it's kind of like a moment of silence for call there. You guys seem like you have a really busy call here. How many sleepless nights do you have on call on average? Or how much sleep do you get on average on call, would you say? Four, five hours. On average, we four hours with a handful of sleepless nights. I'll tell you, so I'm gonna throw in some stories and we'll help you just make you feel better about yourself. See how I figure out this. Story number one, I was an intern, or first year resident and it was, we did buddy call for three months, which was a long time, and we didn't have the intern here. So I was just at the point where I could start doing, like not be on buddy call and panel things on my own and it was 2 a.m. and I called in to see this guy who was complaining of eye pain but he was also totally encephalopathic and homeless and not really with it and I went to go see him, passed out, and then someone said, well he's in DKA, oh yeah, they're in association with MuCorp. This is awesome, I know stuff, you know? So I was feeling really good. I go and do the exam and he's just like passed out and I go look at the CT and he's got sinus disease but that's it. And I thought, yeah, the eyes look fine, I don't think this is MuCorp. But to be honest, if I was really being honest to myself, I didn't really know what MuCorp looked like anyway. But I thought this was MuCorp and I called my resident and I'm like, don't worry, I'm coming in, I've got this. The next day he gets reexamined again and someone said, oh my gosh, DKA with sinus disease in the setting of DKA is MuCorp. And they like urgently, emergently did this endoscopic biopsy of the tissue and it was just floorly positive. And for the next 48 hours I thought I had killed him because if you don't catch MuCorp quickly it's frequently fatal at least to the eye if not to the person. So it was just the most humiliating moment of residency. And I just like residency is over and over again, it's just like gutters and strikes, gutters and strikes, gutters and strikes. Like something goes well and you're like, I've got this and then you just throw like three gutters. So it's endlessly humbling and the taste of tumble pie gets old. The, let's see, can I do the right one? Hold on a second. Okay, so we're talking about the cover on cover test for just a second here. So let's give this patient, let's make this, let's give this patient an XT. And this is on the Academy website, it's pretty nice. So this patient's got an XT and then they're fixing with the right eye. So the cover on cover test, I'm just, really all I do is I just go on and off. On and off, that's cover on cover. And in this case it's really helpful because what do I learn is I do the cover on cover test on this patient. You can tell the right eye's fixing because it fixes right back to the right eye as I uncover it. And then you also see a shift because you can't always tell. Like if, you know, say this is 10, I'm not really sure if that's a strabismus or not. But then you see that they quickly, you see that eye, what we call that refixation movement as you uncover it. Then I go to the other eye and what's gonna happen? Nothing, yeah. I'm clearly fixing to that eye. So that's the cover on cover test. There's also something called the simultaneous prism cover testing. Super confusing. But what you do is, let's say this was, I can't do this, I can't move the mouth quick enough. But the simultaneous prism cover testing is I cover the fixing eye and then I put a prism on the other eye at the same time to see if I can neutralize any movement. So what I do is I put prism here and then at the same time I put the prism on and off. But I do the prism and the occluded at the same time. It's a little confusing, but I'll tell you, we'll talk about why we use that. The alternate prism covering is when I go back and forth. So you can see a refixation movement each time you move back and forth and then you put a prism in front of the eye and then you go back and forth like this until you see it neutralized. So will somebody define for me what a Fourier is? Yeah, it's like a great definition, DM. So let me ask you a question, are our eyes perfectly straight in your relaxed state? Who here's got a console to go look at somebody in the ICU who's got this big XT or ET and they're just totally zonked? And you say, you broke their fusion, why zonk in them? They're snowed, of course they have XT. Most of us would do that or a lot of us would do that. So let me show you what happens when I cover the side. See how it kind of breaks later, you break fusion and then the eyes just say, well gosh, if I can't fuse I might as well just go to my relaxed happy place which may be ET or XT, it's different for all of us. And you guys can test this, I want you to look at that little target right here. Look right there, cover up one eye, hold it there for like five seconds and then switch the other eye. How much does it jump? Does it a little bit or does it jump side to side or up and down the diagonally? Just kind of go back and forth, hold it for a few seconds. Are you seeing a little jump there? Yes. And then go back and forth kind of quickly, kind of go faster and faster and you'll see that jump will kind of slowly come together because if you go fast enough then you'll get back to fusing. But when you break fusion, you'll see a little separation as you go back and forth that image will jump a little bit. That's euphoria. So euphoria as you come off, it's okay to do that, but with the cover on cover test, you'll see a refixation movement, but you're mostly with the cover on cover test. You're not worrying about the eye that you're uncovering. Whoops, it's a test screen. Oh, it's about to tear. So come out of here. So go to those tests. What test detects just the tropia? And what time do you want me to be done here out of curiosity? Is it nice to get out like 10, two, four, two, or eight, okay, I'll try to be sensitive. There's a lot of stuff to cover, but I find that I can only be interesting for probably about 20 minutes anyway. So we'll try to make this too tortuous, but so what test detect just the tropia of the cover on cover alternate cover or simultaneous prism cover? Just the tropia is cover on cover. You're right. Because I'm not giving it time to build and then go back and forth. Is the simultaneous prism cover testing doing the tropia or the tropic anaphoria? Where you go with the prism and the occluder? What do you think? The simultaneous prism cover test? It's the same thing as cover on cover, you're just measuring it. Does that make sense? So those two detect just the tropia and then which one's gonna do the fouria plus the tropia? The alternate cover, because you're breaking fusion and you're letting both the tropia and the fouria come out. What number do we care more about for surgery? That's maybe a bad question. What number are we gonna do surgery for? The fouria plus the tropia or just the tropia? Most of the time. Just the tropia. So actually we do both. You guys say you've got a fouria of 10 or 15 that already puts them at a disadvantage of fusing, right? Because their eyes are in the relaxator out and then you've got another 20 on top of that. I might as well take care of the tropia and then also include the fouria to make their eyes as straight as possible so they don't have to fuse as much of a misalignment. Does that make sense? So kind of tricky question. If the corneal light reflects, suggest your business. So you can see that one eye looks out, corneal light reflects is not centered on that eye but you do alternate cover testing and there's no movement. What is that? And they've got good vision out of both eyes. Yes, that's like an amazing answer because it's correct but it doesn't really tell you why. Brilliant. What specific diagnosis would you give? I'll give you a hint. I'll give you a multiple choice. Anomal sort of correspondence, Anglicapa or extrafolio fixation. And they're 20, 20 on both eyes. Extra corneal fixation. What was that? Extra corneal fixation. Extrafolio fixation, that's what I'm gonna say, extrafolio. So if it's extrafolio fixation, meaning that they've developed a new phobia somewhere else in their retina, they're not gonna have the raw decone density to have 20, 20 vision. So that's a good, love it. Wrong confidence. That's right, that's right. You know, as you know, they say about surgeons. So usually they're right, always confident. I remember there was this person at OHSU that this wise, it was kind of an interesting personality. Somebody else said, oh, you want to say about him? Always confident, it was always confident, but that was never right. So anyway, this would be Anglicapa. Anglicapa meaning that, we'll go over that. But the phobia is kind of displaced either temporally or nasally. And Anglicapa is when it's not aligned with like the pupillary axis. So the eye looks misaligned, but the visual axis is actually straight. Why do we use corneal light reflex? It's quick and easy. Reaches approach to most things in line. Just kidding. Some kids won't let you ultimate cover. Perfect, and is this something you can do on the floor? If you know, I mean, when you're doing a console, you can't necessarily always do like a full motility exam, but you could easily check your pupillary light reflex or eye's are straight. So this is Hershberg. You're just looking for that line to be centered on both eyes because often, you know, after business, you can estimate it by one millimeter of de-centration as 15 prism diopters misalignment. So what is the average size of the pupil? Good to guess. So yeah, so I agree, I probably, and it tends to line in dark, this would be a bad question, right? But the Hershberg test, they always make you memorize these numbers. That if it's the pupillary edge, if it's just off the pupil, it's about 15, so the pupillary edge is 30, if it's in the iris, it's like 45. They're assuming a four millimeter pupil. Does that make sense? So the other ones in the middle, so the radius from the central coil light reflex to the pupil is two millimeters, so about 30 prism diopters. So it's kind of pointless to just memorize their numbers, just to understand that kind of sort of factor right there. Krimsky test, you put prism in front of it to neutralize it until you get it centered, and that's how you know, and then you can actually, you measure the pupil light reflex with prisms, and then book their test, you do a direct ophthalmoscope, and if their eyes are misaligned, you often get a different red reflex. Have you ever seen that as you're looking at kids? I love the direct ophthalmoscope. I think it's maybe, it seems like an archaic tool to a lot of ophthalmologists, but I feel like in the pediatric eye thing, you get a lot, really use it for a lot of things. So we already talked about this, but do you see how an angle kappa, if the foveus, so the foveus, normally the foveus here, but if the foveus up here, the eye's gonna have this kind of, let's pretend this is a left eye, here's the right eye, and we're looking for the bird's eye view. The eye's gonna have this kind of out turning to line the fovea up, but when you look at the kiddo, it's gonna look like their eye is turned out. Does that make sense? So they're fixating, and then I don't know why, but they call this angle between these two, the angle kappa. So for OCAPs, here's how you can remember it. Positive angle kappa is when they look XT, and the way, the memory tool is that in an XT it's less likely to cause amblyopia versus ET, so ET is more positive, or ET is, that's kind of a negative thing. It's kind of lame, but it works. And then just think, positive angle kappa, the fovea shifted temporally away from the optic nerve. So, do you know some examples of when you actually will see like a dragged fovea? R-O-P. Is it typically gonna cause a positive or a negative angle kappa? Positive, because it's usually dragged temporally where the disease is. Yeah. Perfect. Just so people just have angle kappa, it doesn't have to be R-O-P. Yes. Yep. Yep. Sometimes I was just in the loft. The, so, this also I think is critical in understanding to business, but it's like painful. This is I think the wordiest slides I have, so I apologize. So could so many, you can, you're welcome to read, but could so many of their own words define fusion for me? Any thoughts? I'm not mostly asking this because it's just so painful to just be lectured to during the morning. So the more I feel like you talk, the less pain there is, and the faster it'll go by. The sooner it'll be over, right? The, so what is retinal correspondence? Anyone, anyone give me definition of retinal correspondence, meaning retinal points of correspondence to the two eyes? Have you guys heard that term? So what are they, what are the term trying to teach us or explain? Reese, do you have a thought, do you have a thought? Like the receptive fields are the same, and so like kind of like one point of why wouldn't you focus on the same sort of field in both areas? Yeah, and those two areas are gonna go back and communicate to the same part of the visual cortex because the brain has decided those two correspond to each other. They should be looking at roughly the same thing. That make sense? Yeah, it's exactly right. So fusion in many ways is normal retinal correspondence. You've got both eyes looking at something and your brain instead of saying, wait a minute, I'm seeing two images, it takes the picture from both eyes and makes one picture of them. That's fusion. Your brain just sees one picture, but it uses both eyes. The phobia is super sensitive to dissimilarity between the two images. So a little misalignment in the phobia can throw off fusion. But in the periphery, there's larger receptive fields, so they can tolerate more dissimilarity. And that relates to mono-flexation syndrome, which we'll talk about. Another just kind of confusing thing. But it's not that confusing if we kind of come at it just simplistically. So sensory fusion is this idea that the retinal points, the two images are brought into one picture and it relates more to the afferent message. The image, the message from the retina is to the brain. And in comparison to motor fusion, motor fusion is your brain saying, wait, these images are misaligned and it sends a signal back to your extra-ocular muscles to move the eyes to a liner. So motor fusion is the eye movements that you do to get your eyes lined up. Or that your muscles are essentially holding your eyes in a way that keeps them straight. If I was to put a, to your point earlier, if I put a little four prism doctor or base out prism in front of one eye, your eyes are gonna do a refixation movement to compensate for that. And that's motor fusion. Does that make sense? The stereopsis is, so the stereopsis is amazing if you think about this. So if the pictures are mostly aligned, but again, if you, like so, I want you to hold something semi-close in front of your face that has like a little angle to it. And then, and I want you to go back and forth from the two eyes, like maybe kind of turn it, get it to a point where you'll see actually, it's the parts that are closer to you versus further away from you look quite different between the two eyes. And what's happening is that on the image, I mean essentially you have two different vantage points, especially with things up close, which is gonna cause things to look dissimilar onto corresponding retinal points, right? Especially on your objects. Your brain makes sense of how dissimilar they are and what ways are dissimilar and creates artificially 3D. That's amazing, right? So it uses just the minute dissimilarities in order to create stereopsis of depth perception, which is kind of the highest level of sensory fusion. So a lot of what we do in stir business is to, adjust motor fusion in attempts to restore sensory fusion. This I think helps us explain a lot of, again, one of our goals in stir business is this study in the Macomb monkeys where they soak one eye shut. Have you heard of this study? So pretty interesting. The eye that was sewn shut actually had anatomical changes. The eye actually grew and got had a myopic shift and I saw this in clinic just on Friday. There was a kid who had optic nerve hyperplasia in one eye, much more than the other eye. The eye that had it worse, it was like LP or NLP vision, was like a minus seven. And the other eye was like a minus one. And they probably started off about the same size, but they were timing a myopic shift due to the fact that there wasn't, they couldn't, so what I'm looking for. Amatropia, I'm drawing a blank. But anyway, the eye can't focus on anything, it tends to just actually have myopic shift. Yes, amtropization, thank you. So I want to focus on the stir business part. So Berth, what do you notice about the right, so let me just explain this. Your visual cortex has these alternating columns, the correspond to right eye, left eye, right eye, left eye, called ocular dominance columns. You'll notice here that they overlap. What happens between birth and then six months of age? Anyone want to kind of explain to you what, why this looks the way it does? What are your thoughts? This goes back to neurology, one of the ophthalmology. Pruning, snap pruning. Yep, Darwinism taking effect in your brain. Survival of the fittest. The neurons that aren't really helping out much, just atrophy off. But what do you notice about, you'll notice if these overlap, what do you notice here? With stir business. So the stir business one, they ended up cutting a muscle, like essentially cutting one of the ocular muscles so that they gave the monkeys stir business. What do you notice about the ocular dominance columns? They stopped overlapping. They stopped overlapping. So is this monkey gonna have any sensory fusion? So this is what stir business does when I'm treated. You lose that overlapping fusion capability and that's not the end of the world. I mean, you still want their eyes to look straight for other reasons, but they're not gonna hold it straight. They're gonna lose a little bit of their binocular function. Congenital E.T. is like the most common one where it's an early enough stir business that you see this happen. And these kids get all sorts of weird stuff because they don't have that normal fusion. They get DVDs and lateness dagmas. This is two boys to talk about. Let's go skip this. Just for kind of how your OCAPs take, we'll just hit these two laws. The Sherrington's Law of Reciprocal Innovation. Do you guys remember this law? So Sherrington is your muscles are trying to share the work. So if one guy's turned on, the antagonist needs to be turned off, right? We always talk about this in like anatomy with the biceps and the triceps. So if the biceps contracts, your brain also tells the simultaneously the triceps to relax. Make sure it's extra medium. That's where you can't see, you know. It's a lot more than that, be careful. The joke. So who breaks this law? In what case do you not get a muscle relaxing when it's antagonist contracts? Any guesses? Starts with a D. Dwayne's. Yes. So Dwayne's, the sixth nerve, it's not, there's various of Dwayne's, but to simplify it, the sixth nerve nucleus doesn't reform. So the third nerve tries to go over and innervate the lateral rectus. But what happens is when the lateral rectus fires, the medial rectus is simultaneously fired and both muscles pull the eye in, which causes the lid fissure narrowing, not because it's actual eyelid innervation, but it's the eyes being pulled back into the glow and it causes the eye opening to close a little bit and that's Dwayne's. Herring's law, what's, so Herring's law, any guesses? So it's up there, I guess. Also could be through this. It's the yolk muscle. So if your left lateral rectus fires, what other muscle's gonna fire? Right medial, the yolk muscle to it. Yep. Who breaks this law? Pressure. Oh no, sorry, I have a question on that. So does dorsal midbrain, with the co-contraction stag, is that the same co-contraction of muscles that causes that or is that a different etiology? That's a good question. So I mean, by its name, yes, it is silent because you see the greatest picture that you'll see on that dorsal midbrain when they're trying to look up is that you look at it from the side and we just will show the eyes are moving in and out of the socket. Have you seen that? So it's not just their fluttering. If you look at it from the side, so if the patient's looking straight and you're looking at it from here, their eyes will be moving in and out and that's because those muscles, again, are simultaneously co-contracting in kind of a nice stag-moid fashion. So who breaks this law? Any guesses? One eye move up while the other eye stays straight, DVD. So a superior rectus should go up on both sides but you'll get one eye that'll float up. So if a patient is not fusing, what other options are there for the brain and the eyes? So let's say I got a misalignment. What options does my brain have? Press the other eye. Nice, perfect. Come back, you're doing it, you're nailing it. What else? What happens if you don't suppress the eye? What do you have? Diplopia. Diplopia. There's a third option. Anyone know? Change the retinal correspondence. Anomalous retinal correspondence. So I'll explain that real quick. I never understood this until, again, fellowship. So anomalous retinal correspondence, it's a state that's superior to total suppression where your brain says, well, you know what? Maybe I'll just change the retinal points of correspondence since this T is my left eye is always 20 doctors of ET. Why not just adjust to make that those two retina points of correspondence? The, let me explain this real quick just a couple of pictures. So here's two eyes that are straight. So the image falls on both phobias. Normal retinal correspondence, perfect. You get an eye that's turned out. So you see, where's that image gonna fall? Temporal or nasal Diplopia? Yeah. So if you have seen this all day long, at some point, this eye is either gonna suppress or not be diplomic or your brain can say, you know what? Maybe I'll just change my topographical map of the retina as far as what my brain perceives and I'll just have the temporal retina correspond to the phobia. That makes sense? The temporal magnet, I should say. What's gonna happen though, when I cover this eye, am I gonna fix it still over here? If I cover this eye, am I gonna fix it with a phobia? In the case of anomalous retinal correspondence. So typically, when you cover up the other eye, they'll fix it with a phobia. If you don't, if you still fix it with that, then it's extrafovial fixation, which is somewhat of a different animal than anomalous retinal correspondence. Super confusing, but Angle Kappa doesn't shift when you cover it up. Anomalous retinal correspondence does. Does that make sense a little bit? Because in Angle Kappa, what are they fixating with? Extraphobia or phobia? Phobia, yeah. So again, same thing, it's nasally here. So, how do we test for sensory adaptation? This is a rough chapter to be assigned to. Just please give me that credit. This is boring stuff. It's not boring, but it's tough stuff. So thank you guys for hanging with me. You guys are doing awesome. Again, I think this is really complex just to understand all these tasks. So, can someone explain to me how the worth four dot test works? We're gonna go through all these tests because we don't use them, but we use the worth four dot. So here's your flashlight. Here's the glasses you put on. If you were wearing these glasses and I cover up the green eye, what are you gonna see in the flashlight? How many dots? So you're gonna see, the green ones are gonna disappear because you've got red filter, yeah. And then if I cover up the red eye, what are you gonna see? What is the, so the white dots is gonna turn whatever color you're looking to, right? I mean, I think on that backwards, so when you're wearing, when you're looking to the red, you actually don't see the red. Sorry guys, sorry, I don't know. So if you're looking to the red, you're not gonna see the red. If you're looking to the green, you're not gonna see the green lights. And there's a different number of them because that way you're gonna see the white one just goes to either eye. So through the red eye, you see one, two, three dots. Is that right? It makes sense. To the green eye, you'll see one, two. If you're looking through both eyes, you have the potential to see four, but if you have a strabismus, then you'll see as many as how many, how would you guess? Would you see eight dots if you have a strabismus in your diploma? What would you see? Five, you see, yeah. Three out of the right, two out of the left. That makes sense. And you confuse them if your eyes are straight. So if a patient puts these on, and then you say how many, and you're holding the flashlight, and then you ask them how many dots do you see? And they say three, what's going on? What are they doing? Suppressing which eye? So if they can see three, they can see they're seeing through the rest of the suppressing their left. So you're right, they're looking through the right eye, suppressing their left. Let me ask you a question. This is going to explain mono fixation syndrome. It's not as complex as it sounds, but what did I tell you about the peripheral retina versus the central retina in terms of its ability to tolerate dissimilarity? The peripheral retina. Exactly. So if you've got a small strabismus that you can't really correct, what are you going to suppress first, the central or the peripheral vision? What's going to be more intolerable? Central. So mono fixation is you have a small enough angle that you can fuse peripheral retina, but you just can't quite fuse central. Here's the next confusing question. How do I test peripheral retina with the worth forward test? Do I hold it up close or do I go far away? I'm going to test peripheral retina up close because the images are going to be actually, for me that's counterintuitive, but when they're up close, they're going to go more to your peripheral retina. When they're far away, you actually just are fixing, it's actually quite central into your phobia. So all mono fixation is is peripheral fusion, central suppression. So when you put them up near, they see all four dots because they confuse the peripheral retina, but when you go in the distance, they say two or three. Again, two boring to talk about. So we'll call it there. I'm not sure you can get a few weeks, but we'll talk about the three step Biotowski test, which I think is actually, again, difficult to understand if you just kind of memorize it, but we'll walk through it. We talked about the bag lead lenses. Yeah, so that's a good question. The bag lead lenses, there's the ones that have just like the striations that cause essentially like linear glare, right? So bag lead lenses have these lines through them that you still can see what you're looking at. So say I was looking at Ashley, I can still see over anything that's light that's gonna cause these like horizontal bars. When you're doing, when you're trying to test sensory adaptation, the red-green test is a problem. The worth four test is a problem because it's dissociating, meaning you see two very different things on each eye and the way, you don't know somebody's sensory adaptation unless you're giving them a normal picture on each eye and letting them figure out how well they fuse it, but you can't do that, you have to put some test on them. So bag lead test is less dissociating because I can still see through it, but it's causing these lines that I try to see at the lines that the striations and the lenses make line up. And the same thing like when you put like a red, like the Maddox test, just the Red Maddox test, you just do one. So they hold a bright light. I'm gonna see a big line because when you look at the light through those Red Maddox lens, it causes lights to turn into a line. So you see like a, and then the other I leave uncovered. So I've got one eye looking at a white light. I've got another eye looking that's creating a red line. Depending on how you hold it, you can see if those two inner parts are separated. There's also, there's like the after-image test, we have under monocular conditions, you have them stare at one line that's like this, and then you cover the other eye, you have them stare at a line like this and they have open their eyes. And now there's no suppression or test or interference with their vision, but you see those two lines intersect to make a cross. And anyway, it's really complex and actually nothing can help me helpful. But then the Orcas looks at the test on it. So sensory adaptation is trying to figure out how well are they really, is there a sensory fusion? Stereoemtosis is a great test for that. So that's a really nice, simple one. Lastly, so I know Chris Ritz is doing the resident side of wellness and actually the fact side of wellness. So just on a side note, we've got to come up with these interventions to improve wellness. It seems counter-intuitive that I'm gonna make you do something to add to your stress. That's gonna make you feel more well. But I want you guys to think about, I don't know, have you guys seen the Headspace app? Have you guys ever heard of this? This is meditation app. I started trying it after most things in life that I make fun of, I ended up doing it later on. So most of them I criticize somebody for changing lanes without a blinker. I'll do that within a week. So I want to make fun of meditation. Actually, it's kind of cool. So Headspace is like a $100 app that the university is providing for free where you have to take 10 minutes out of your day, which is really tough for me. I'm sure it'll be more so for you. Just to like clear your mind. It's kind of nice. So do you guys have any thoughts on things you think that would be helpful in terms of wellness? Adding a fourth resident was probably critical. Will you think about it? I'm talking to Chris. And then my next lecture, I'd love to talk about a few things that we'll start the lecture off by talking about cognitive behavioral therapy and just healthy and unhealthy ways of thinking. And because I just found as a resident, I was often so hard on myself and then I would do things, I just would get trapped into really unhealthy thinking. Like I would do nine things well and then I would miss the, you know, miss a new court patient and then just think I'm a total failure. Like, I mean, they're all good or all bad. It was strikes and gutters. All of a sudden, you forget any strike you've ever thrown, you just focus on your gutters. And I think as a resident of your, I was constantly falling into these traps of just getting into unhealthy thinking about giving myself the benefit of the doubt and maybe being a little bit kind of myself in hard times. It's really, it's a tough, it's a tough season. And so we'll talk about those things. I would love your thoughts, get to Chris about how we can maybe try to improve wellness in the program. Thanks, guys.