 There's a little bit of overlap, but, okay, so, you know, you have a variability of patients coming in. Renee talked about patients when they say one eye is not seeing as well, the kind of easiest diagnosis or easiest patient to work up with us is if they say they're completely blind and this is non-organic, so, you know, in this case you just have to demonstrate that the patient can see really anything that will prove, you know, that gives you some evidence that they're inconsistencies. So, like Renee said, you just want to really, every observation you can make to help you confirm this is going to go towards your kind of assessment that maybe this is non-organic, so, washing them, walk into the room, conserving them, the handshake. So, there are some tests that people might think are vision-related but are really utilizing proprioception, so fingertip touching if you have people close their eyes and touch with their fingertips, that is something that someone should be able to do if they are blind. Also, I haven't seen this in action, but a signature test, people should still be able to have a fairly reasonable signature with their eyes closed, you know, without vision. I don't know if you've ever used that one, but after having vision, a cute change, yeah. And then there are reflexes that we can't, you know, people don't suppress, but the mirror test utilizes kind of the meiosis convergence and accommodation and basically if you put a mirror in front of someone and have them and move it, they basically follow their face and they have all of those reflexes. The optokinetic reflex of the ok and drum, you know, seeing the movement of the eyes, they basically can't suppress it, but these are tests, if someone's like saying they're 2060 or 2080, that doesn't really help because that's not proving that they're seeing, you know, better than just having, I think okin is around 2200 vision. So, you know, that is where we, you have to kind of take some other tools out of your toolbox. Pupil testing, you, if the, just wanted to make note that if it's a normal pupil exam, you cannot have a normal pupil exam if you have bilateral occipital disease. So, that's just something to keep in the back of your mind, but if it's completely normal, it's either kind of that's the differential or there's a symmetrical visual, you know, damage to the visual pathways or it could be non-organic. There's some tests that utilize shock values, so if you're kind of like, you know, scaring them or putting a fist up and they respond to that, that's, you know, kind of indicating that they can see tearing reflexes within some papers. I don't know how, you know, this one is probably not going to be super useful, but again, anything you can get to try to help you just, you know, make this diagnosis, everything is useful to just put the whole picture together. VEP testing plays a pretty limited role. It's not, again, it can kind of maybe add to some, add to your evidence, but you can have variability in it with either vision or having no vision. So, it's not something that's used a lot for confirming it. I know Renee talked about the base-up prism test. You can do this if they're still saying they're, you know, completely blind too, because if they do have eye movement, that means they're seeing something and this is just the diagram of having the base-out prism that will induce the shift of that left eye, nasally, because it will move towards the apex and then that means that the right eye will have kind of a, associated to caught out to the right and then it will reconverge, so that's the base-out test. Then as Renee said, the vertical prism disassociation test and so, again, you can either see one image or you could see one better if you truly have decreased vision in one eye. Yeah. Yeah, oh. Why a vertical prism test do you see, like, can you use such a small, like, four base-up, four prism doctor test, but with horizontal, you expect them to converge it after you use the same amount. Because it's our vertical ability to fuse is so much less. So, you know, with four base, four diopters in front of one eye, you're going to, they're going to be pretty far dissociated and you can't just converge them versus horizontal, you, we have a better ability to kind of fuse and bring those images together. So, and, you know, then we can disassociate those images and have these two distinct kind of lines that we're looking at. Horizontal and fusional amplitudes are up to about 30-35 prism amplitudes. So, you can use that horizontally. That's why just such a small four prism doctor will allow a person to re-converge a vertical fusional amplitudes. You don't want to do that one or two. So, once you have a congenital fourth, you should not be able to use four and that's why you don't really fixate, again, the vertical prism and why you should see two. So, following tests, this Renee went over that and then there's the red-green do a chrome test. So, if you put a red lens over the bad eye and a red-green filter and then you have the, you know, red-green snow and chart, the green lens on the other eye will prevent the good eye from seeing the red letters. So, you can see if the patients are able to read the red letters than they are seeing with their bad eye. There's bottom up acuity. So, and, you know, I think this is just a side note. If you suspect non-organic vision loss and you're going in to do these tests, fogging bottom up acuity, you have to know what you're doing and kind of have a plan and really be confident in what you're doing because it has to seem smooth, it has to seem very natural and you can't be kind of fumbling around and with like the fogging test, you really have to, you know, start at the correct place and then go from there. At the bottom of acuity, you want to start with the smallest line on the snow and chart and say, okay, like, read this line and then say, oh, well, let me make them a lot bigger for you. Move to 2015 and then maybe 2020 a few times and say, oh, you know, these are pretty big, like you can't read them and then you keep going up but by the time, you know, you've already done five lines there, they might start reading them and that gets you at a much better visual acuity and started, you know, 2050 and going down and they say they can't read them. So that's a way to, oh, and I guess we kind of transition to binocular reduced vision. Of course, if someone's saying they can't see anything, that wouldn't be very useful but the binocular reduced vision is kind of, like the 2060, 2050 range is kind of hard. That's the hardest one to really nail down because there's these subtleties that you kind of have to prove that they can see more and then if, you know, there's some visual aids you could put trial frames in and say, you know, these are special magnifying lenses and try to see if they can see with that even though it's just their regular prescription, potential acuity meter, maybe you could, they could see with that. With visual, if they're reporting a visual field, the automated permitry testing isn't the most useful just in terms of really getting good data for having non-organic vision loss. Sometimes you can see a clover leaf pattern and that's based on the fact that those four dots, those four points that are circled are kind of initially tested and then tested again. So it's just kind of the pattern of non-consistency that you can get these clover leaves. But one point is that in when they've done retrospective reviews and other studies, central scatoma are actually really rare non-organic vision loss. So if you do have a patient and you get a visual field and they have a central scatoma, you really need to work that up more and really prove that there's absolutely no other organic disease. The tangent screen test is great for this as well and it's done for those of you who haven't gone to neuro-ophthalmology. It's, you know, in the hall, it's fairly fast but you do a nine millimeter, by the books, a nine millimeter white stimulus at one meter so you can do one eye at a time. And basically you have, you bring it into the view and mark where the patient, where their peripheral vision, you know, starts. And then you move them back two meters and you repeat it with an 18 millimeter white stimulus. And so if it's an organic visual field defect, that field should expand to twice the original size. And so if it doesn't expand, we call it a tubular or a gun barrel field and that is kind of again suggestive of non-organic vision loss. So then there's confrontation testing which is really useful. You know, if we are seeing patients on QALR, we're not in the neuro-ophthalmology clinic. But again, you kind of identify where patients can't see. You can do a modified tangent screen or use the same principles as a tangent screen if they are saying they can only see a little tube. If you move back and it doesn't expand at all, that's helpful. You know, if you've identified that they can't see, let's say, you know, inferiorly into the right and you're trying to just get more info about that, you can ask them to tell you when there are no finger scenes and continue to flash fingers. And if they, every time you put up fingers, they say there are none, you know, that can give you some hints. And if, you know, a lot of times if you put something in their visual field, they might have a saccade down and they might hit your hand too, which is an indication they can probably see your hand. But, you know, they may not be saying they can actually count your fingers. And then a Goldman-Permitree testing. As you start with a big stimulus and you're testing either clockwise or counterclockwise, kind of the classic finding of this inward-spiraling eye-softer and as large or stimuli are employed, there's further constriction. This doesn't show the overlapping, but it's basically like spiraling in and then having the larger one spiraling in too. And so, again, if you see any sort of a midline or vertical step, you really want to, again, just really prove to yourself and work up more maybe that there isn't an underlying organic component as well. So, like Dr. Choi said, if you've gathered all your data and everything is really pointing to non-organic vision loss, you want to really stress that there's a really good prognosis and that visual recovery will happen, but we just have to, you know, we'll do everything we can and we'll watch and continue to follow, but this should turn out well. You want to get patients the way out in some sense that they can come in and say it's better without having to feel like they have to explain what happened or feel bad about it, but the big thing with the non-organic vision loss is we just can't miss organic disease and there are diseases that you see very little change on an exam unless you're really looking for it. And in terms of studies that have been done, reviewing kind of how much organic disease is also interlaced with non-organic disease. There was a retrospective review of Portland of 133 patients that have the diagnosis of functional vision loss. And they found that, well, sorry, 19 people were pediatric and 19 of them were female. The most common pattern, had reported a normal visual field with decreased vision, and then 53% in this review had some abnormal finding on the neuro-ophthalmology exam that was organic. In their study, too, they found that, like, a central scatoma was, that was a very big indication that something additional was going on. There was another retrospective review of 140 patients and there was a smaller amount, but they found coexisting organic disease in about 16.7% of patients. So that's, this is just, that's the part where we can really get in trouble. And in neuro-ophthalmology clinic, we do see patients who have, the hardest patients are the ones who have real disease that's, you know, going on and then an overlay of functional vision loss and sorting out that is very, can be really challenging because you want to, you know, see if their disease is progressing, if there's changes and then also, you know, try to take, take all the information as seriously, but try to, trying to sort it out can be really challenging. So that's why having all of these tools to use is really useful because the more information you have and the more you can kind of support your theory, either one way or the other, the better it is and then you can kind of follow it over time, too. So, you know, it's not useful to confront patients, but again, just reassurance, giving them a good prognosis. In this retrospective review is the patients who have been reported to improve are younger usually, and then they don't have overlying psychiatric disease. And then, and, you know, there's a variable and variability in the reports of how many people have kind of experienced resolution of all their symptoms, but been reported between 45 and 78%. So, all right. Do you guys have questions or other comments about all that? Yeah. I said general rule, I know there's more information than better, but are you safe by just probably employing maybe one or two of these techniques and then saying, of course, after ruling out their organic cause, could you be safe by just doing maybe one test or two tests and I think it is functional? Do you need to do four or five tests? I mean, it depends on what the patients are. If they're saying they're completely blind and you've proven by, you know, two ways that they can see, that gives you some evidence. I think, I mean, the more you have the better, but I guess it's, if you feel comfortable with that and there's no other red flags, it's just kind of a clinical, that's kind of a clinical. But there's no legal issue or like definition as to what you should do. There's no legal definition on what you should do, but if you're seeing a patient who has perineoplastic disease and you have done one test where they maybe felt the heat of your lamp on their face and they started tiering instead of having vision and that's what caused the tiering, there are certain tests that are less likely to stand up in court and so don't think about it necessarily as, I'm going to have to defend this in court, but think about it as, I need to prove to myself and to Dr. DeGree and Dr. Warner and Dr. Crom and Dr. Katz when they ask me how many tests I've done and what I've done that I've done a good thorough work to make sure, yeah. And in the Neuron clinics, we usually do two or three or four tests to confirm that they are in fact having some functional vision loss, yeah. What's the name of the stereo testing that doesn't have those monotonic fluids? Is that like the stereo testing? Because like that Tidmist one, like you can look at it just without the glasses and you can kind of tell. There's another one that doesn't have those. I thought I was just like, but only the first ones have the first samples and then after that. I mean, it's just smaller, I mean, you can still tell. But there's like a whole other like stereo test at the moment. I haven't, yeah. I don't know. I haven't seen that before. Yeah. Are we use that stereo acuity that does have, there is an article that looks at what the acuity is if they can see a certain number of animals, a certain number of dots. It's not perfect, but it does, there is an article that correlated with what is your acuity with a certain number of dots. I think we have it up on the wall in clinic two. Yeah. What other questions or comments have you guys had hard ones on call? Yeah. What have been your tricks for those? Or not tricks, but how have you kind of sorted it out? I have like a girl that, such as like an LP in line, but she had like full color vision and like I did the base out, the base down test. And those were normal. And she also had like a positive like a can response. She had no APV. No, right. Normal. She had come in and gone to another hospital and they had scanned her already too and there was like a heating mask. You have to be fully alert to have the okay and drum work, right? Focus on the black line versus the white line and follow it. But there are like 17 different stereo tests. Oh, and then, sorry, this is another, this is a slide that was back. This is kind of, can go along with having, you know, non-organic disease, but if you have some of the other things that people are complaining of, if they voluntary flutter, so irregular brief bursts of rapid frequency low amplitude eye movements without a slow phase that can be this voluntary flutter. If the patient's reporting a gaze palsy, you can use these, you know, oculosopholic reflex with the doll's head testing or an okay-end testing, mirror tracking, caloric, sorry, that's wrong, but caloric testing is of course like an extreme, but those are ways that you can try to sort out if they're saying they have a gaze palsy. And then spasms of near reflex are episodes of intermittent convergence with increased accommodation and myosis. And that's another thing that kind of can fall into this non-organic disease category. But with spasms and near reflex, you know, you look, when they're having these, these kind of spasms, you look at their pupils and kind of the eye movement and you can help, you know, diagnose that as well. So quiz questions. This one is so hard to renaise, but we'll just make sure you guys understand it. What's number one? Yes. So, I mean, this is a little straightforward. Of course, if their eyes aren't moving during a mirror test, that's not very helpful. Proprioception results are normal as they should be even if you don't have vision. Eyes moving with rotation of an okay-end drum will establish the presence of some vision, not sharp vision, but that they can see. And then, like we said, a normal pupillary reaction to bright light can, you know, it's helpful, but it still is something that can be present with, like I said, bilateral occipital disease. And then, what's number two? So, I guess this question, I don't know if it's really the best. I think a Humphrey visual field is probably, I don't know. It could be helpful, but it's a little bit, you know, with the confrontation to visual field, we have a little bit more up our sleeve to kind of move back or do different things in their area of vision loss. So, I said C, but a Humphrey visual field. I mean, in neuroclinic, I think the Humphrey visual fields we get in patients that have, are there really useful in patients who have organic disease with an overlay of functional vision loss because you can really follow the defects, but if it's just a true functional vision loss, I've seen that the confrontation and tangent screens are maybe a little more useful, but I don't know if you guys, Dr. Crum and Dr. Degree, would agree with that. Of those three, the Humphrey would be the least helpful because it often is abnormal. But not maybe in a pattern or, you know, you can say it's abnormal, but it can be abnormal and people who are just bad test takers are unreliable and so it doesn't give you kind of a, it doesn't expand or have these other overlapping eyesopters or spiraling ins. And then what's this one? So again, you have the base out, so it'll, the eye that has the base out prism over it will shift towards the apex of the prism, so it'll shift inward and then have a conjugate, you know, outward shift of the other eye, which will then converge and move inward again. So that's the pattern.