 So Anna doesn't think that I can cover all the visual fields in ten minutes. Do you want her to cover visual fields? No. Okay, so just sort of to review, I'm going to just hit some of the highlights of how to do visual fields, how to document visual fields, and then the anatomy of visual fields. Well that's going to be very brief because most of that's going to be covered in the cases. So, you know, the concept of the island of vision in the sea of darkness, where the steepness of the slope of what you're able to see kind of increases rapidly and further out of the gap to the point where you can't see any of it all. It's normal not to be able to see behind your head if you're a mom. This is the most basic way of documenting visual fields, is what you're taught and do every single day. You're fixating your eye and patient's eye and presenting targets in all four quadrants of the visual field, not out here, this is extremely insensitive. The semaphore of you, when we're teaching the medical students next month, that's the habit that must be extinguished. I just do one or two fingers. Some people do one, two, or five. You have to make sure that the stimuli are presented straight on rather than kind of on an angle. This is the bowl that is used for automated perimetry, also for kinetic perimetry. The difference being that with kinetic perimetry the targets of varying sizes are brought in from the edge, from the non-seeing to the seeing, and the patient indicates the first point that they see them, the smaller the target, the closer towards the center they see them. When you join up those lines of where they do see them, it makes an ice octer, and this is sort of a demonstration of the kinetic versus the static perimetry. Here is, of course, the physiologic blind spot. It's an absolute scatoma. There's no retina there, therefore there's no vision. The other format that we use quite frequently is the tangent screen. So easy to use, so very useful. It can be used for non-physiologic vision loss for children and for people with very bad vision. It can also be used for extremely sensitive testing of the central vision for drug toxicity. Some people use a central red target. You document the visual fields by presence or absence of finger counting or hand motion or light perception in the four different quadrants, the right on the right eye, and the right eye on the right side, left eye on the left side. The only thing in medicine that is documented this way, backwards. Okay, so just to sort of cover the field of the anatomy of the vision, I love this picture just because it's like antique, but basically the concept is the right side of the brain deals with the left half of the vision, and you can see here how the left field of vision goes to the right part of the retina of both eyes and gets transmitted here over to the left side of the brain through those radiations and the tracts. The anatomy is dependent on, sorry, the visual field is dependent on the anatomy, and it's one of the nice anatomic correlations that we have in medicine. It's one of the reasons I think why neurothemologists are such happy people. So this is the field of it. This is the physiologic blind spot where the optic nerve is coming into the back of the eye, and then the fibers radiate in these patterns. The retinas is a demonstration here of an area of damaged retina just above the horizontal refa was going to lead to a scatoma down below. I actually like to use the physiologic blind spot as a reference spot, so if the patient is saying that the defect is towards their nose, they're going to be looking in the retina in a corresponding location compared to the physiologic blind spot. This is just another graphic representation, and I'm including this because it also talks about the pupillary fibers, specifically talking about the optic tracts, and the fibers that deque off the tract in the superior colliculus, the breaking of the superior colliculus, taking care of the pupillary responses, which becomes very important in an optic tract. Lesion characterized by an incongruous, meaning different in the two eyes visual field defect, often with a relative affluent pupillary defect, which is small. There can be damage to the nearby structures, which would include the temporal lobe, the thalamus is just right above here, and you can get associated damage with the cortical spinal tract as well. You can, because of this, get a pupillary defect without a visual field defect. It's pretty rare. The relative affluent pupillary defect occurs in the eye contralateral to the affected tract because of the different percentage of fibers that are crossing in the chiasm, and that's the correct way of considering it. I personally sort of think of it a little bit more in a mechanistic way, so if you have a left hemianopia, you have a bigger left visual field than you have right visual field, and therefore there are going to be more pupillary fibers represented in that bigger visual field, and therefore the defect will be in your left relative affluent pupillary defect from a left visual field defect from the right tract. This is just a nice little example here, stolen from Stanford of a tract lesion. The chiasm is just right here, and then the tracts are going here to the lateral genicula. This is meant to explain why you get bowtie atrophy, but we're not going to talk about that. We're going to talk a little bit about the lateral geniculate, which is an extremely small structure right here, shaped like a Napoleon hat. As you can see how close it is also to the thalamus and the descending corticospinal tracts. The lateral geniculate lesions are extremely rare, but much discussed because they're so cool. The lateral geniculate lesions come in two varieties, anterior, posterior, and I don't know if you're going to be talking about those more, but this is a representation of a classic anterior lesion, and this is a posterior lesion. I personally think that you need to just memorize how these look, because it's just too hard to go through the math every single time to work it out, but you can have your own way of remembering this. I'm thinking of this sort of looking at it anatomically as more of an anterior kind of a thing, and that is a little bit more of a posterior kind of a thing, but out yourselves out, you can figure out a way to memorize it yourselves. Retrogeniculate loss can occur from a variety of pathologies, including strokes and masses. I don't know that there's necessarily any way of figuring out before imaging what it is that's caused the defect other than by the classic did it come on slowly or gradually. Geniculate lesions are often seen with small strokes and masses, and particularly with thalamotomies, which are movement disorder surgeries. The temporal lobe lesions are typically superior visual fields. The parietal are typically inferior visual fields. Temporal lobe pathology would include things like hallucinations, seizures, oras, specifically rising fear, deja vu, jame vu, those kinds of things. Parietal are often associated with language or association problems. We'll talk a little bit more about that. Excipital lesions are often associated with reading problems, but can be almost asymptomatic as well. I don't think I'm going to have time to talk about the macular splitting and sparing. Temporal lobe lesions, as I said, can be associated with these hemipirotic hallucinations, language problems as well. This is a nice example of a temporal lobe lesion way up high. One of the things about the anatomy of the visual field that you can count on, and if you can remember this, it can be very helpful, especially the temporal parietal, is that the lower portion of the retina goes to the lower portion of the optic nerve, goes to the lower portion of the chiasm, and goes to the temporal lobe, and then goes to the lower portion of the lobe. The right and left and the chiasm and all that sort of stuff is happening independently, but the lobe stays below. So all of that, all of those lower things are going to give you an upper visual field effect. The parietal lobe, if you remember, is kind of up here, upper portion of the retina, upper portion of the nerve, portion of the chiasm, skipping through the temporal lobe and up through the parietal lobe is going to give you lower visual field effects. So the upper portion of the occipal lobes. And so to the extent that that's another useful way of trying to remember the anatomy, that can be helpful. Parietal lobes, lesions can be associated with some really interesting neurologic syndromes, language problems, hemisensory defects in the dominant hemisphere and Gershman syndrome of agraphia, acalkylia, finger agnosia, and left-right disorientation, which is extremely hard to document, especially if you have finger agnosia, because if you're asking which finger it is and they can't even name their finger, then how do you know? Kathleen and I have had a little thought experiment about that one. The parietal lobe, the non-dominant parietal lobe is associated with spatial disorientation, constructional apraxia, dressing apraxia, shaving apraxia, and anisegnogea, an awareness of the defect. And I just wanted to show you a nice parietal lesion. You can see that it's down below fixation. It is incongruous, but it's not exactly the same in both eyes. So we're not all the way back to the except for the lobes. And then this is my favorite picture of a letter that a neighbor wrote to my mom, which I think you've probably all seen at this point, which is, dear Ray, how are things going? Things are really great, blah, blah, blah. Have a little stroke. Don't let me drive. I don't know why. I'm going to first see you again soon. So obviously this is demonstrating left-sided neglect, but she's no language problems, right? She's riding away like a champ, and she is not really aware of exactly what happened. And just to touch on the exceptional projections, of course this is, remember, as I was saying, the inferior rim of the calcine cortex here is from the inferior, inferior, inferior. So now projecting to the superior portion of the nerve, the central fibers are more posterior, and there's this little rim of very, very temporal fibers that take care of the temporal crescent, which looks like that. So this is a nice example of the left eye visual field, the right eye visual field, and then the both eyes together visual field, where somebody has a hemianopia, was sparing of the temporal crescent. This is a really nice example. Sorry, the lesion was right there in the oximeter. That was oximeter, yeah. And so would that be more anterior or more posterior, more of the front end of the oximeter lobe or in the back end of the oximeter lobe? The back end. So the center fibers are involved, and the very, very anterior end of the oximeter lobe is spared because that temporal crescent is still there. So the posterior pole is more affected than the front end of the oximeter lobe. So it wouldn't be a crescent in that anterior oximeter lobe? Yeah, if the whole oximeter lobe gets out, then you get out your temporal crescent. You lose your temporal crescent. Not demonstrated on Humphrey visual field testing. Is it not demonstrated on Humphrey just because it doesn't go out? It doesn't go out far enough, because you can see it's way the heck out there. That's like at 60 to 80 degrees. But the patients may say, well I think I can see something out here and you try and get a stimulus into there and it's hard because it's way the heck out there and they can't really read with it or anything. I don't know if you need this. Do you need this for... That was something from him. There we go. All right, so now it's all cases all the time. The quiz is going to be interspersed, right? Well, it's some... Yes. So I got a little carried away, as I always do, so 10 cases and I was like, that's a lot of cases. So I kind of put a quiz between them. 45 minutes? I know. Well, we're going to work through it and as you know I like things to be a little interactive, so we're going to keep it a little interactive, keeping in mind the entire time limitations. But with visual fields, especially, I feel like you have to really talk through it and I think even the most experienced of us have to sometimes, I think, think deeply when we look at visual field deficits because of all upside down, right, left anatomy. So we're going to start with this visual field and so I'm going to get one of you guys and maybe let's start with one of the junior residents describing this visual field and then we'll talk about what this is and why this is happening. So, Tara, do you want to start? Yeah, so there's like some scattered scatomas almost like in the same location. So why don't you start with like, remember how you were taught to read an X, right? Yeah. So this is a chest X-ray of the right person, maybe you don't know, and what eye, so what kind of visual field is this? Okay, so this is a Humphrey visual field. And what kind of Humphrey visual field is it? A central ting. Well, see that little 30 there on the right? Oh, 30 dash two. So you have one, two, and three, and this is 30, so it gives you 30 from fixation, and which eye is this? I think this is the right eye. It is the right eye, and why don't you think this is a blind spot? Why do you think it's a physiologic blind spot? Physiologic blind spot. Because it's only located superior to the right eye? Well, no, but I mean, sure, but that's true, but sometimes because of the indices of the test you might not get some points there, but what you're seeing here is the fact that it's kind of within seven degrees or so of the fixation, and where you see here it's kind of within the 12 and a half that we normally have between the blind spot, the physiologic blind spot and the fixation. Myself and Paras here? 12 and a half. All right, so, and okay, so it's a Humphrey 30 dash whatever. You won't know this, but it's a 30 dash two visual field of the right eye. And as you mentioned, what kind of describe what you're seeing? So there is, it looks like an enlargement of the physiologic blind spot, and then there is a scatoma that looks like it could be near a fixation and then four other scatomas kind of in the midperfury of the all. Yeah, so I mean the gist is that you have these depressed quadrantic visual field deficits in each quadrant you have that, right? So does anybody recognize kind of pattern recognition what this field is? So let's start with categories. Is it brain, nerve? It looks retinal? Retinal? It looks retinal. Yeah. So to understand this visual field you really have to understand how Humphrey visual field algorithm works. And I understand that you guys have regular lectures and rotation kind of describing the algorithms and how to read visual fields. But what Humphrey visual field algorithm does it usually checks the quadrants first and kind of more central quadrants just to see what the kind of the kind of general threshold is in that quadrant. And so if the patient falls asleep at the beginning of the test or doesn't recognize the test is started they actually miss those areas that the Humphrey visual field algorithm checks. And so you get this visual field where you have these isolated quadrantic defects. Now this can be of course retinal lesions but you have to look at the retinates and make sure they correspond to these particular lesions. Does that make sense? So Lee, do you want to take this one on? So this is a gentleman we saw a few weeks ago and he's got thyroid eye disease and had multiple surgeries and he does his visual field and this is what it looks like. Looks like he broke into it. Did he start it to the patient? Yeah, that sounds good enough. So this is a Humphrey visual field 30-2. Sorry, I'm going to take it back. Is it 30-2? Or maybe 30-2. And why is that? Because he has his 30 there. So the question for you is what amount in degrees of visual field is a Humphrey 24-2? Humphrey 24-2 tested. And I'm giving a hint. Horizontal and vertical. So this is 10. This is 10. This is 10. Maybe it's too early to do math this morning. Well, it's 24 on the other side. Sorry? Yes. So 24 and then 30. So it's a combination of... Yup. It is turned into 2-2 math. Alright. And so in the horizontal versus the vertical you get 30 plus 24, 50-4 degrees. Do you know the reason why we get 30 degrees in the nasal quadrant? No. So Humphrey visual field was designed to check for glaucoma. So by design the test is to check for visual field deficits associated with glaucoma. The earliest visual field deficits commonly associated with glaucoma is a nasal step. So this is why you have 30 degrees here and that's why they kept it when a 24-2 algorithm was designed versus a 30-2, which is an older algorithm. In order to speed up the test reduce the amount of visual field but increase or still keep your sensitivity up for glaucoma to see the field deficit. So hence you have the 30 degrees nasally that is kept in the 24-2. Alright, so the pattern recognition of this visual field is what does that mean? The patient wasn't attentive during the testing. When during the testing? I think later on. Correct. So this is again an important aspect of interpreting visual fields is understanding how the visual fields are performed and how they're tested. If we use the information that we got from the previous case we know that these central quadrants are tested first and so when the patient is paying attention they've got their central quadrants in each eye but then they kind of fall asleep or they're tired or they're malingering and then they kind of give up and stop pressing the button. And so you have this pattern of a cloverly visual field test and it doesn't always indicate that the patient is malingering but it can also indicate somebody who is tired and just falls asleep at the end of the case or at the end of the test. Nika, do you want to take this time? Sure. So this is a visual field defect I'm not sure what it is maybe a 24-2 of the not sure well I'm not sure which eye as well the pattern deviation the maybe the left and right eyes which shows a central OK So this patient is a 79-year-old man who came into our clinic a few weeks ago and he complained of difficulties driving and his wife thought he kind of drove the road a little bit before she warned him and on two separate occasions these visual fields were reproduced this was a reliable visual field and what is really important to note about this field is kind of symmetric what I'll talk about throughout this lecture is about how we're looking at the flavor of the visual field so it doesn't always have to be perfect because of the imperfections of our field testing but the important thing is when you look back at the fields you have to think about the pattern and the flavor visual field rather than just well it doesn't quite fit we're going to see a few cases later on that show us that but this is basically as you can see almost like a ring scatoma so it doesn't quite form a ring but almost there so that's what I mean by the flavor so the vision I put for you here on purpose because it is not a central visual field but a central kind of ring scatoma and you know the definitions about central, paracentral versus mid-perforal ring scatomas kind of are beyond our discussion here but it's important to understand what things can cause it because there's a lot of visual field deficits that can present that way and it's relative to the anatomy that Dr. Warner had discussed earlier so what I want you to think about and tell me what clinical tests would you be able to do to confirm that this is a maculopathy versus an optic neuropathy so we talked about this and the visual field approach to visual fields or approach to vision loss a few weeks ago just a few tests that you guys can think about sorry, yep, very good multi focal multi focal, yeah I mean that's great and of course we talked a little bit about color vision but you have to think about how you're going to differentiate in this patient between maculopathy and optic neuropathy and of course part of it is your clinical exam this patient was sent by an ophthalmologist he had a full dilated exam and this was sent as an unexplained vision loss of this particular pattern so I don't have a color photo for you because it's not impressive and we actually didn't take it but I will show you this and what this patient has is large areas of geographic atrophy and as you can see on the OCT you have outer retinal atrophy which is consistent with GA but on clinical exam it's difficult to see because there was not a lot of pigmentation there was not a lot of drusen it was just atrophy and maybe if you're not looking carefully enough you're just not seeing it well so again the clinical exam is important but this was an ophthalmology referral and it's easily missed these kind of things you might not always look as you expect them to look I just want to point out again this is talking about using the physiologic blind spot as an anatomic reference point so you know that you can't really see it very well because it's an absence but Anastasia why don't you point out that's where the physiologic blind spot is on that visual field and the same thing on the other side and so you could say okay well the physiologic blind spots here and then the foveas here and then on the other side you've got about that same amount of space so you know that the pathology that is being demonstrated by this visual field is between the physiologic blind spot and about the same distance away from the macula so if you kind of look at that that's where the central 10 degrees of the 24-2 is representing is this kind of center area within the arcades and you know again the other thing to point out is you can look at this physiologic blind spot and see well is this a psychocentral scatoma but as you can see the visual acuity was quite good and of course you have the corresponding pathology to see on my presentation they didn't do a OCC no because they didn't see anything on the macula and thought the macula looked good it was really dramatic here but on the real life it didn't look good yeah again this is because of the imaging we used right so you wouldn't see much you might see a little bit of color difference in the retina just because of the ARP atrophy but you know if you're just doing a slit length exam and you have a quick look and say you had a occipital lobe lesion or say you had visual field that had congris-central scatoma and you were trying to decide whether or not this is maybe a rebel lesion which is an occipital lesion would you have any kind of visual acuity changes that would kind of induce that maybe this is more of an occipital versus well I mean you have to think about where that your center of your visual field is and what fibers correspond to that so you'd have to have like bilateral occipital lesions with only affecting the macula that gives you this which is what can happen so the answer is with a unilateral occipital lobe lesion there shouldn't be any acuity loss but with bilateral occipital lesions you can be anywhere from 2020 to blind but looking at those visual fields that's definitely a good thought you just want to look at each one of those maybe the black one the greater than .05% chance that this is abnormal right the ones that you're surely abnormal and you look at each one and these are not congris the things you want with an occipital lesion which is a great thought you really want those to be a little more congris but if you look it's like it's not congris right it's almost like the number of spots that are different is way more than the number of spots that are the same right alright so this is a case of a 24 year old who came in because she had these new headaches and she had some visual lures and her PCP watered MRI and it was okay and so she was told to go see an eye doctor so she comes to see an eye doctor and she comes in with this so again maybe Reese, pattern recognition so it's 24-2 visual field and then it's she's got kind of bilateral generalized constriction anything else you can call this um keywords Central Ireland yeah I mean this is we call this a ring scatoma okay so you got central so basically it's a scatoma that's centered on the visual axis or the visual center and I think this is a really really really important differential diagnosis to understand that I don't think you guys get taught enough and um you know a ring scatoma like I said is an annular defect which is centered on fixation and it encircles fixation but visual acuity is preserved okay so I briefly mentioned that um you can get central paracentral or midperforal ring scatomas it depends on the site of pathology um we saw kind of more of a central a ring scatoma in the case that I showed previously um the paracentral usually incorporates the blind spot so this is where you see um things like glaucoma, coalescing inferior to your arcuate causing a ring scatoma or you can see that of course in any type of optic nerve disease with arcuate defects and then midperforal is usually seen with a non-advanced retinitis pigmentosa or a faked correction where you get the jack in the box phenomenon that we often talk about um and that usually is between 30 and 60 degrees which um not often um if it's early enough not picked up on a Humphrey test because of the amount of testing that we do but sometimes is so um this is a acute macular nerve um yeah it's a specific condition that we don't fully understand yet and basically it's just uh like we think is an inflammatory or possibly even vascular condition where you have acute paracentral visual field deficits sometimes you get central visual field deficits but then the central vision comes back and you get this paracentral defects that stay um it is it is an entity um that is relatively new um but it has been um described in the literature uh before now one thing I did want to mention you know we did see the um uh geographic atrophy in the previous case that I showed you um all the rest of the things I think are a little self-explanatory but um this is an interesting timbit um there's a kind of a not so new entity but people talk about something about coffee and donut maculopathy so um you know there's cases been reported of patients who drink like 20 cups of coffee a day so be careful and don't do that but the thought behind that is um when um we have a dentist in a vasculature that uh basically vasodilate um retinal vasculature and coffee is thought to be an inhibitor of that and so it causes vasoconstriction so uh presumably uh when you I guess drink a lot of coffee and continuously vasoconstrict your uh perimacular fiber of perimacular vessels you have um an impairment of the macular blood flow and that in turn causes uh perimacular deficits or visual field deficits so it's kind of an interesting thing that's kind of relevant um to us but um phobia is good because it's still getting the the uh uh perfusion from the coroid because it's so thin um but you get these paracentral or central abarynx sputomas okay so important to keep in mind so this particular patient um had uh these peripheral retinal pathology that you can see here and um um she had a retinitis pigmentosa okay this is the next case 64 year old man with blurry vision in the left eye I think this has to be an easy one just to be quick okay what does this look like Ashley? uh so this is a 24-2 and a uh inferior um hemi defect in the left eye so altitudinal so uh since this is neurophthalmology um what do you think this is classical as a student? yeah so this patient did have an AION and why does this make sense with this OCT? you're part of the nervous you're part of the legal field so the one question I do want to ask you though is how long do you think it's been since he acutely developed an AION? over four weeks yeah so I think usually kind of six weeks six to eight weeks is when you think about atrophy setting in um to the optic nerve so um it's important to kind of realize that if there's no edema that it's probably been an extended period of time now if again I think we've kind of discussed this point before but if I just see atrophy like this and nobody's told me that he's had swelling what would I be concerned about? yes so compressive optic neuropathy so again think about it if you do not see swelling in an AION classic an AION presentation you have to rule out compressive optic neuropathy so if this person came and swollen you would scan it? well if it's a classic you know presentation and he's got the risk factor yes then um probably not but if as he did not and it was not a classic presentation okay 35 year old woman with this visual field deficit Kristen? yeah Kristen we've got Kristen very good it's like bonus points for a neurologist I don't know what that means so what's supposed to be there? what's normally in that area? so enlargement so this is a bilaterally enlarged blind spot very good and again you should have a differential most common things that cause an enlarged blind spot um of course dyskidema is one of those things that we always have to think about and you have hope that you do look in the back of the eye to confirm or deny that um you can have peripapillary retinal lesions and um coriditis or something like that or atrophy um or peripapillary atrophy just in myopic tilted nerves that you can get enlarged blind spot and um one other entity that's not really good to think about because you actually don't see much on examination and often um it's missed because unless you do specialized testing um you will not pick this up um so acute idiopathic blind spot enlargement or variation of the mutes syndrome is important to keep in mind especially when you have a unilateral um isolated temporal deficit that's an important thing to rule out so it doesn't send you down the garden path looking at brain lesions okay so this lady had um alright so this is the next case um and uh again this should be kind of your garden variety of things that um we need to think about and like I mentioned to you before because of the inconsistencies in field testing and lack of exact precision um we look at the flavor of the visual field so this lady came in um because she went to see an optometrist to get by focals um he did a screening visual field and he noticed this visual field deficit so you guys can just generally yell out what do you think this is yeah so this is a by temporal visual field deficit and um you know yes there's a few lesions here but again the flavor is that it does respect the vertical midline so you really have to think back right so you have um which portion of the superior versus inferior visual field is located um is it inferior or superior inferior visual field so that would correspond to correct so what is the most common lesion in the pituitary pituitary adenoma right so macro macro whatever but that's the most common so this is naturally how it works it expands and it pushes on the chiasm it compresses inferior chiasm and causes your superior visual field deficits alright so this this is her um MR which uh showed of course chiasm compression from below I don't know if you can like even see a little bit of it there and um she was operated on alright next case is a 41 year old woman with a three month history of decreased visual acuity in her left eye she was sent by an optometrist um because he thought she had a CSR and um uh she was sent to us to treat it and uh I uh this is where I profess my love for amsla grids because I really do like them and um I I want to kind of briefly mention the fact that um you should really differentiate on amsla grid whether you have like a field deficit or metamorphopsia so um you know with things like CSR you actually get metamorphopsia because there's some movement of the uh of the retina kind of side or forward and there's distortion so you always get metamorphopsia type field deficits whereas with a field deficit or absence of RP photoreceptors gangram cells or whatever else or damage to them you actually will have a deficit um or blurry spot or a visual field deficit so it's really kind of important for you um to ask the patients what exactly they're seeing if it's a metamorphopsia or a visual field deficit and um we had a look at a back over and we're like what? I guess pretty good macula let's at that time was like 2013 we did a serious OCT so um she uh of note is the fact that she had a visual acuity on the right of 2020 and on the left of 20 over 100 okay but normal visual fields oh sorry normal um um not normal macular exam so we did a goldman visual field and so if you look at this visual field um I really again want you to think about that flavor okay so like what is the general area these sceptomas are in there so where is my mind going exactly and the reason why you know it's you know okay fine say maybe that's in a large blind spot but it's not really going right like it's going straight to the vertical to the vertical midline there and the same thing there now this is again to speak to the in precision of our visual field testing she has even though you don't quite see the involvement of the center with this particular goldman you know that the center is involved because why she's 2100 right so she has a central visual field deficit on the left very good so really important it doesn't look like your classic your you know wedge defect or you know kind of your junctional scatoma but this is this is your junctional scatoma which is maybe a little bit harder to pick out and you're not always going to see kind of where it's described nicely and drawn in with the wedge defect but this is your junctional scatoma so this patient had a large intercellar mass that was about two and a half by about three and a half centimeters it was elevating the optic chiasm clearly compressing one of the interuptic nerves and the concept that we always talk about in junctional scatoma is what it's a bit of a theoretical thing and anatomically not supported but what is the name of very good so von Wilbrensney is something we talk about theoretically to convince ourselves that this junctional field deficit makes sense so this patient actually had pituitary apoplexy because she had some methamoglobin in the in the lesion and so she was operated on so is that just kind of you can see that just like or regularly on the just quick question this is so bit anatomically this is a left junctional defect correct so she's come exactly she's compressing her left optic nerve right and so you just have to always think about chiasm with the junctional so this is one case before we do the quiz this kind of incorporates the fuel things that Dr. Werner talked about and kind of helps us get more conceptualization of the anterior visual pathway so it's a 49 year old man who presented with a headache and ptosis on the left and double vision and as you remember I talk about the three musketeers of extracurricular motility so you always need to talk about the pupil he had some light near dissociation of the pupil on his left side and he doesn't typically get headaches and this is what so again what is so take this one step at a time what is the flavor of this visual field deficit or kind of where's the biggest abnormality very good so write homonymous write homonymous and if you forget about this it's right homonymous and I need a few more qualifiers there or one at least one right sorry so we talk about complete and incomplete homonymous visual field deficit if you forget about this because we'll talk about this in a second but this here is a complete homonymous visual field deficit where is the lesion with complete homonymous visual field deficit we have tracts so actually you cannot say there's nothing in that visual field that qualifies for a location once you have a homonymous visual field deficit that is complete it is retrochiasmal so you just there's just no way to tell so it's either imaging or some other auxiliary testing we can talk about later they can help you distinguish where exactly it is but there's some help here so if you look at let's talk about this here so this visual field deficit which is an inferior temporal on the left right what on the left correct which what could this be what pattern could this be associated with so if you look at this and you look at that what could be hiding behind this homonymous field deficit very good but also if you just were to isolate the left eye and just look at that what would this give you an idea so you have options here because you either have a visual field deficit this is complete so you think it's retrochiasmal somewhere you think maybe that could be by temporal so that locates you into the into the chiasm right or you can have this altitudinal visual field deficit which points you to the to the nerve and if I gave you some clues here so there was a relative after people are defect on the left and this pattern of the OCT and you're going to probably wear it to the Saturday Christmas party very good alright so you are really worried about this I think you more exhibit a little here you think you want an anterior here exactly so I just wanted to go over this so we can put this together and the problem here Dr. Warner had mentioned about an APD on the opposite eye here unfortunately because you have this optic neuropathy with global atrophy here now it doesn't quite meet the opposite eye or APD criteria subsumed into the optic neuropathy alright so this gentleman had this large pituitary macro that was like invading all tissues around and involving the tracts as well which is why you get the bowtie atrophy and why you get a homonymous field deficit alright here's a quiz and then there's a few pieces after we have time but progressively harder essay points essay questions we got you multiple choice this is separating the week from the jab here guys there's a signed reading for each lecture right we did the reading when they cut down on our lecture schedules we pumped up the reading and plus we brought Anna on board this is what I was discussing with Dr. Warner yesterday I was like well I can use a quiz to just reiterate which we just learned or we can use the quiz to learn some more we'll do half and half alright good alright as far as we're going to get that's the answer to this question very good D so why wouldn't it be a full field that'd be normal in both right no differentiation whatsoever why is it not a DEP it looks a nerve but what would we do with maculopathy or optoneuropathy the VEP is actually very driven by the folial response so you can get reduced VEPs with optoneuropathy and maculopathy so that's not the test to use again these are the things we think about when we order testing why is it not EOG what do you test very good and of course multifocal ERG will tell you that there's abnormalities good okay what about this one sorry be very good so it is actually more common in children than adults you have supercellar mass which it is probably one of the more common causes of a C-cell nystagmus even though C-cell nystagmus is very rare and it does have a favorable survival prognosis of about 98% of 10 years or so but we talked about this right so inferior versus superior visual field deficits and which part of the chiasm is being compressed you just need to understand the anatomy of the chiasm of fibers to answer that question do you need the list of the ring scatomas to help you or do you guys I think this is just pretty much from that list so I think you can mark that as you wish so does anybody know what riddle phenomenon is and it's neurological that's why so um so I forgot so riddle phenomenon is actually this visual field phenomenon where if a patient has an injury to generally the occipital lobes or occipital cortex sometimes it can be seen with other lesions as well but they perceive moving targets but not static objects so if there's a car parked there they do not see it but as the car moves they begin to see it and we think it is because there's kind of more predilectional visual system to respond to better to moving stimuli rather than stationary stimuli and the last two questions I think are really important to know about because Hemifield riddle phenomenon is a relevant phenomenon clinically because we see patients with bi-temporal deficits and so basically what this is is that you can see if the patient has any predilection so this is double vision without any peresis of extraocular muscles and any predilection of a patient with visual field deficit where you have a phoria so either a vertical an exo or an esophoria all of a sudden because you don't have overlapping visual fields you're losing that fixation so you know how we break fusion when we do our tropion phoria testing you're pretty much doing that with eliminating their visual fields so eliminating their hemifield and so once fusion is disrupted the existing phoria just has no the existing phoria just has kind of no check on it because of that fusional drive for it to keep the eyes together so once the fusion is disrupted the pre-existing phoria comes out and becomes a tropia and so patients will either have a crossed or uncross diplopia depending on what their tendency was prior to having their hemifield visual field deficits so well described phenomenon it is sometimes asked about on boards and this is why I put that up there and then the other important thing about bi-temporal deficits is this phenomenon of post-fixation blindness and what that deals with is the fact that of course your temporal visual field is affected and so when you're fixating on a near target so when you have a near target again this is your phobia and this is your center so you're not you're missing, your visual field does not allow you to see anything that's post-fixation so patients are not aware of it but they're actually going to be missing so fixating a near target they're missing everything that's located in that area because of that overlap so again it's a related to fixation when you fixating a near target when you're looking far away that's not an issue right because you're not overlapping but here because you are you've got this post-fixation blindness phenomenon almost never described by patients but we actually had a guy at the VA who that was his presenting complaint because he was a truck driver and he observed in the long hours that when he was looking at the car right ahead of him he couldn't see the cars beyond which incredibly rare observation I've never ever heard anybody mention it ever before or since except for this truck driver and so it that's not really a near target but the same principle applies it's not an infinity so anywhere closer than infinity this will of course apply post-fixation right okay so good observation alright so I'm going to stop here what do you have two or three two oh I want that third eye first is the third eye refractive okay guys I can't go