 All right, so we're going back to Vienna All right, and this is the Schoenbrunn Zoo. This is the oldest zoo they claim in the world. So We don't know everybody always claims are the oldest in the world But in any event the oldest world oldest zoo at least in Europe And so this is right on the grounds of the Schoenbrunn Palace and you've got here You can see this is one of the residents after a night on call totally exhausted Relaxing, you know eating all those Cheetos that are in the machine because that's all you have time to eat and some Black bears they're kind of cool because I'm not sure What kind of black bear this is because they've got this little facial coloring on here and your obligatory polar bears It's always fun to watch And again, these are a couple residents lamenting the weekend call. Oh God primary called me a hundred times All right, enough. So we want to talk about the optic nerve today And when we're talking about the optic nerve, I mean you guys are all aware of the picture of the optic nerve And so when you're looking in at the optic nerve, you know, first of all, it's the border should be sharp It should be flat. It shouldn't be elevated. It shouldn't be depressed or concave You know the color is kind of this You know pink sometimes yellow color, but it shouldn't be white and you see that there's no hemorrhages around there There's no vessel engorgement. And so that's a normal looking optic nerve And here's the optic nerve in a sagittal view. And so when we think of the optic nerve anatomy, all right I like to use the analogy of a fiber optic cable So first of all optic nerve is made up of the ganglion cell axons which then come out through the nerve fiber layer through the lamina crebrosa Tina what happens to the axons once they get beyond the lamina crebrosa? They become myloneated. So there are Alligadendrocytes that live in the optic nerve here that myloneate them. So think of an axon as a single fiber And it's got mylone around it. So it's got it's an op. It's a it's a fiber optic cable It's got a little bit of insulation around it Now they're also organized into these columns right here in Weisch. What what goes in between these columns of these axons here? The P.L.Septe P.L.Septe. So this is like a bundle of those you know fiber optic bundles that are right there. And then finally The entire cable is buried in the ground with steel around it And then what surrounds the whole cable there? The optic nerve sheath. All right. So each individual axon has mylone Which the oligodendrocytes put on it once you go post here to the lamina crebrosa and then they're bundled together and they get into these columns with these little P.L.Septe That are going along then and the whole thing is wrapped in the optic nerve sheath All right And here we can see that in cross-section All right, so optic nerve sheath Let's see. So Brad what what is this tissue underneath here? Um, so we have the arachnoid in the subarachnoid space. All right, so remember this is the second cranial nerve And so just like the brain it's got Dura around it i.e. the optic nerve sheath and then it's got the arachnoid granulations Subarachnoid space what runs in here? Um, so you have the little like arachnoid processes. What else is in here though? Um, so you have vessels as well. What is in this empty space here? Fluid CSF exactly CSF and so that's important CSF flows through there. So anything that Increases CSF pressure could be transmitted out to the optic nerve and that's important to remember that What are these two structures right here? Central right in the artery, central right in the vein All right, so remember we talked last time how the artery in the vein share a common Advantitial sheath so you can see right here where arterial sclerosis Can push on the vein next to it that can cause stasis or arterial sclerosis Not only causes central artery occlusion, but central vein occlusion All right, so what are we showing right here? Rachel just keep going around And so there's the optic nerve sheath what are these guys here? Exactly these are the little arachnoid granulations when you look at these I oh another question here. What stain is this for bonus points? This is a trichrome stain So, you know trichrome stains connective tissue blue It stains kind of mesenchymal tissue nervous tissue red So this shows you the optic nerve sheath the arachnoid arachnoid granulations and then these are the little pl SEP day kind of separating off the bundles of the optic nerve As it comes down and here you can see it in kind of a longitudinal cut Here you can see the pl SEP day The axons here now we'd said oligodendrocytes live in the optic nerve What's another cell body that lives in the optic nerve trees? All right, what more specific actually astrocytes So astrocytes live in the optic nerve too So when you think about what kind of tumors you can get of the optic nerve Astrocytes lived in there So you can get astrocytomas and there are some little microglial cells in there that do a little bit of cleanup action But remember there's astrocytes that kind of live here and their cell bodies are kind of in between here in the The columns of the axons Here again, just showing you that common abititial sheath between the central retinal artery in the vein All right, we're just going to show a few simple things. I guess we'll just go back around the room. Yeah What are we showing here the optic nerve? tempo side There's that paler Tissue which probably is a sclera So it couldn't potentially be like a small coloboma Not quite a coloboma yet, but that's a good that's a good thought But if if you look at this boy, that nerve is just really small You've got kind of almost a double ring around here. So this is optic nerve hypoplasia Pretty common entity that you can see and the interesting thing about this is it really doesn't affect the vision a whole lot I mean you look inside and these people tend to have normal vision. It's bilateral. It even can run in families So this is a hypoplastic nerve You know as opposed to like the crescent that you get in a myopic nerve You know, which is a big nerve and you get a big crescent around it where you can see the sclera showing through This is a tiny nerve. You're going to see almost a double crescent around So this is a hypoplastic optic nerve All right, Chris. What is this? This looks more like a optic nerve coloboma. Optic nerve coloboma. Exactly. What is a coloboma? Coloboma is where you have a failure of um, the embryonic vision to close Okay So if you remember when the eye is forming you get indentation Of the neuroectoderm and then it forms kind of that bilayer Cup, but then as the vessels are coming in you start to get it sealing off and it seals off at the equator And then moves forward and backward. So when you get colobomas It's usually at the front part of that which is inferiorly in the iris Or it's at the back where it seals off which is inferiorly at the optic nerve So this is failure of that original embryonic fissure to close And this is just bare sclera. You're looking at here now this can affect vision because you know You've got some intact fibers here, but you're going to have a big You know superior or arcuate defect or big superior altitudinal defect there Because these are inferior and that's actually just kind of bare sclera that you're looking at This is kind of what I call the most severe form of a coloboma. Catherine. What is this? Exactly. So what's the name we put on this? Morning glory and so you can see it's almost like it's it's out of focus because it's almost like it's pushing away from you It's it's pouching out the reason it's called the morning glory malformation is this is the morning glory plant And so it looks like a trumpet horn. So if you think about it, this is like a big trumpet horn moving away from you So this is kind of the ultimate Optic nerve coloboma. This is a morning glory syndrome. And um, this is the morning glory plant. That's why it's named that way All right, what are we looking at here? Tina So there's a kind of a small outpouching Around four o'clock in the nerves that looks like a Small optic pit All right, so that's another thing that can form there and people have argued if optic nerve pits are Kind of put together with colobomas or not or if they can occur separately and I still think we don't know exactly what Causes an optic nerve pit, but you can see right here. There's this little optic nerve pit That's there And when you look at it, this is actually a pathology You'll see that there's this little pit that's right here now What do we worry about with an optic pit that can affect vision? So the biggest thing is you can get a little bit of fluid underneath the macula there Exactly so fluid can leak out where this optic nerve pit is and it could actually leak out because usually these are temporal And it'll leak out underneath the macula so you can get this This fluid underneath the macula and you actually get a little focal detachment of the macula And some people will argue that this fluid is csa Others will argue that it's got some components of vitreous in it And so what you worry about is not so much that you get that focal nerve fiber layer defect But that you get leakage of fluid and these are tough to treat because it's not like you can put A wall of laser here to get rid of the fluid because if you do then you'll have a huge You know scatoma in your macula and so these are very very difficult to treat What are we looking at right here? So we have these Looks like the nerve fiber layers has this whitening. So it's probably because it's myelinated Okay, so remember we talked about myelination starting posteriorly to the lamina crevosa And what's interesting is is when the optic nerve grows The nerve grows, you know from the from the brain from the original, you know embryologic Outpouching that comes out the nerve will grow out But the myelination starts at the lamina crevosa and then grows back Toward the you know toward the optic chiasm and backward, but sometimes some of those um Illegal dendrocytes can end up forward to the lamina crevosa and then you'll get Myelinated nerve fiber layer now. These are usually congenital So when you look at these they're they're there from the first time the kid is examined And it's important that you note these because you don't want You know a guy to get in a car accident and then they go to the ER and someone looks at an undilated people says Oh my god, papillodema You know, they start drilling holes in the patient's skull to relieve pressure You know, so I always let patients know I say you've got a curiosity in there Some of the insulation on the on the nerve fibers that shouldn't be in the eye is in the eye So if anybody ever looks in your eye and says, oh my god, just let them know that this has been there since you were born And so now interestingly enough, this really doesn't cause a whole lot of Of vision symptoms I mean you might if you really check carefully could get like a big blind spot or some focal scatoma here But you know the nerve fibers still function through that area It's just that the myelin will you know dampen down the light getting through some of the fibers underneath it So this is one of those things that kind of looks pretty exciting and alarming and the patient doesn't notice a thing What are we looking at right? All right, so what exactly are optic nerve drusen? Uh, so they're calcifications And so they're they wouldn't show up Unless you you know, you may not know what they are do you do like an ultrasound for sure Exactly now these are sometimes if they're buried they're really hard To discern and so sometimes people will come in and the ox would be referred in for a peppalodema And they'll be concerned that there is an elevation of the optic nerve head and you look in here And this one is a little bit more prominent. You can actually see the little bumps in there But you know if you just looked at this this nerve head is elevated. It's it's pushing up toward you But it's because of these bumps here. And so when drusen are on the surface You know, you can see them pretty readily, but when they're buried then it becomes tricky because you you often can't see them when they're buried So this is just showing you some of the different Presentations here. You can see again Classic drusen you can see them here here Not pretty good, but sometimes it's just a little hard to make those out when they're when they're buried deep And of course, this is an end stage. This is rare that you know, they'll you'll get it to this area This is an end stage drusen. You see how the vessels are all compromised Now, you know, it's tough to tell sometimes the difference between peppalodema And buried drusen and so That's a tough thing. And so you mentioned one of the things that we can do to tell the difference Which is an ultrasound and so because these drusen they're they're highland eyes But they have a lot of calcium in them calcium reflects ultrasound And so if you take a b scan And you know, dr. Harry's wonderful doing this, but you guys can even do this You know you take a b scan in the retina clinic and you just get the shadow to where the optic nerve is coming out And you slowly turn the gain down and what'll happen is a lot of the eye will disappear But the little bright spots are on the optic nerve will stay there because as the sound waves hit that calcium It bounces back really strong. So calcium gives you a strong signal back And you can even see it on a ct scan And I'm sorry I copied this and that's bad. I'll have to get a newer one But you can see that that the drusen just kind of light up here on a ct scan This shows it matter It is bilateral but can be asymmetric So sometimes you'll see it and you'll scout you in a lateral But then you can do a scan and you'll find that it it'll be buried sometimes So this is a better one. See right here In here And this shows you an actual eye that has been cut in half Sagittally, this is the optic nerve head going out and here's a large Calcified drusen. It's in front of the laminocrobrosa Kind of underneath the perincoma the optic nerve And then here we have a nice path specimen. Here's the Center of the eye over here is the optic nerve going back laminocrobrosa and here we have this calcified highland eyes Jews and sitting in front of the optic nerve and then underneath the nerve fiber so you can get focal Nerve fiber layer defects from these drusen the problem is again, we don't have treatment for these And so i'll send them to brad cats because he's really interested in following up these people but I you really can't do much with them. And so fortunately people don't get serious law, you know, loss of vision I'll often get some focal You know bundle type visual field defects Here's another one Drusen buried here Sir have you ever found in your In your experience that coming up anti glaucoma medications has slowed down the progression of any Field loss or have you not seen that good question people have of sad that if the Optic nerve fibers are compromised already with this drusen underneath them that even a slight increase in pressure can maybe cause Further loss and so you certainly want to keep the eye pressure as low as you possibly can But there's been no good evidence that the so-called neuro protective Either pills or drops do anything with these but you definitely want to Make sure that you don't put even a moderate pressure on top of this Right brad what do we see in here? So this is a color from this photo of the nerve we can see that There there's some blurred disc margins consistent with optic nerve edema I don't see any Hemorrhages really So this is an end stage, but it's definitely I don't know stage two Okay, well and you really got to be careful and I'm glad you said it the way you did you said optic nerve edema Papal edema you can get I got nailed on oral boards on this Papal edema by definition is optic nerve swelling secondary to increased intracranial pressure And so you can have swollen discs from other things And so be careful if someone shows you a picture of this on boards and you say, okay, this is a swollen disc If this were bilateral and associated with increased intracranial pressure, we would call it papal edema So be very careful to do that because the the guy kept saying oh, so You could tell papal inside of then I said oh Then I had stopped myself saying no, no, no, okay It's a swollen disc if the other discs were you know elevated and the pressure were high it would be papal edema And then he goes they never tell you yes, correct when you do no boys. They go Okay, then they flip the page You don't give you any feedback so But there are other reasons for an optic nerve to be swollen aside from papal edema So be careful when you do your definitions All right, so this is just one that's Probably more severe and and what do we see in here in addition to what he saw in the previous one seeing hemorrhages more tortuosity of the The vessels make some tortuous vessels Hemorrhages on the surface of the nerve Obscuration of the vessels exactly obscuration. So this is uh severe Um, whatever grade there's one scale that goes from one to four There's another scale that goes from one to five This would be a four or five depending on what scale you look at so severe. Um, this turns out to be papal edema Okay, so when we look at it pathologically, here's the laminar crebrosa back here Here's the edge of the square there. Look at the optic nerve head. It's markedly swollen But look at how the vessels are engorged and look at the hemorrhages on the surface. So you get Hemorrhages On the surface you're getting gorgement of the vessels you get it literally gets swollen and pushes forward So pushes toward you when you're looking at it. So that's a classic path of papal edema And you can even get forward bowing of the laminar crebrosa from the pressure coming from behind So those are the laminar crebrosa fibers Pushing forward and so kind of the opposite of glaucoma remember we talked about glaucoma How the fibers excavate and you know, the laminar crebrosa gets pushed backwards this they're all Pushed forward. So the opposite direction with papal edema All right, what do we see in here? There is some obscuration of vessels on the disc. This doesn't look like classic papal or classic optic disc edema though What else could cause kind of a picture like this? Exactly. So you want to start thinking about ischemia Okay, and so You know, you want to worry about aio and you know anti-ischemic optic neuropathy and what is the two ways we kind of Break that down. What are the two different things that can cause that? Arteritic like GCA or non-arteric. Exactly. So you always want to keep that in the back of your mind, you know You don't want to miss an arteritic You know aio and versus a non-arteric aio. So a lot of it's going to be the history So what's the history of a classic aio and these who? has 70s Yeah, 70s Kind of sudden onset vision loss it like me like blurry in a particular area Completely painless the other eyes to find And in fact sudden onset oftentimes they'll even wake up with this And so it's it's like an old vascular path, you know old guy with diabetes and hypertension and You know, he wakes up in the morning and says yeah, I just can't See out of part of my eye something's funny and the reason people think that's that's it is remember your Blood pressure kind of bottoms out right before dawn And so oftentimes that's when these aio ends will occur Now what else at least in an acute phase can give you a funny swollen disc also aside from ischemia How about just just optic neuritis or pepillitis exactly so you can also get You know inflammatory autoimmune other things and causes so swollen disc You know, you get one of these on boards You're in big trouble because it It can be anything and so be sure when you do an oral board that you list as many things as you possibly can In order to do this sir What's the mechanism for looking swollen when you have an aio and isn't just the nerve fiber layers kind of dying out It's actually swollen. So in ischemia you actually get swelling from the ischemia In optic neuritis you actually get inflammation of the fibers behind there and then you get secondary swelling coming up if it's acute Now sometimes you can get Optic neuritis the nerve looks fine. You don't see anything initially and then you start to see You know losing of the normal color and pallor later on All right. So the reason I wanted to show this is We we said as as rachel said, you know, you can get aio and and again, it's non-artoretic It's the person we talked about but don't forget you can get temporal arthritis Which is the arterioidic form and you don't want to miss the arterioidic form because patient may present with Loss of vision in one eye But not only can they lose the vision in that eye, but if left untreated they can lose vision in the second eye also So you don't want to miss an aio and so trees. So what am I showing here? All right, so actually I'd like to start from the inside just because I'm oscd. So Here's the luma and here's the intima. What is this layer right here? To elicyclamina and then here Muscular media and then here Advantish, okay, so I want that artery right now. That's a normal artery So if you do a temporal artery biopsy, that's what it looks like. Now you you may ask Why do ophthalmologists do temporal artery biopsies? That's a good question Just because historically patients present with sudden vision loss And so, you know, usually we're the ones who do the biopsies You know, you'd think that you know, you'd refer to somebody else or the plastics guys would do them all But you know, even general ophthalmologists do temporal artery biopsies. It's just something in our Purview because we see the patients How does this look different than the previous picture? Yeah, look the intima is massively thickened Don't have internal lastic lamin is gone Boy muscular media, you know, I can't see anything at low power And not only that, even at low power, there's these little tiny blue Dots around the edge. Let's look at higher power And what do we see here? Thus the name some people call this giant cell arthritis and so You get epithelioid and giant cells and for some reason they cluster either Internal to the muscular media or external to the muscular media So they can be around the internal lastic lamina. They can be external people have argued Is this an attack on the internal lastic lamina is an attack on the muscular media Is there a bug in there, you know, for a while the rheumatologists and brad were Had me looking at a whole bunch of these to see if there was a specific bacteria that could cause these Fortunately didn't turn out to be but we still don't know exactly what causes this. We just know it's an older people It's a disease not just of the You know the the temporal artery or the short posterior ciliary arteries behind the nerve It's a disease of kind of medium small arteries through the entire head That even the entire upper body And so these people may have Loss of vision, but then you talk to them carefully and you say do you have intermittent claudication and then they go What? So but so you want to ask them specific questions and you want to say, you know, when you chew Something does your jaw hurt? they say Yeah, do you have trouble getting up out of chairs? Do you feel stiff and tired all the time? You've have like some low-grade fevers and so Ask them for the, you know, polymyalgia rheumatica type questions and you'll find they often have these So you don't want to miss temporal arthritis. All right, so tina you suspect temporal arthritis You haven't had a biopsy yet. What blood test do you do? esr crp Okay, esr crp Let's say the they are high enough that you're suspicious Then what do you do? start them on steroids before you do a biopsy and then you usually have You talk to one to two weeks after starting steroids to get the biopsy And that's critical Don't wait for the biopsy to start the treatment because again, they could lose vision in the other eye if it's positive But you want to get the biopsy within seven to ten days because Sometimes if you're on steroids for a long period of time, it'll calm the inflammation And then the biopsy becomes difficult to read You know, there is an entity that we call healed arthritis But that's when you know, I'll look at a biopsy and they'll say someone's been on steroids for a long time Nobody's done a biopsy you look at you say well Turn on the lactic laminates chewed up. My skeletal medias may be gone But it's a really iffy call so you really want a positive diagnosis because steroids are nasty Medicines especially in old people they can run into all kinds of side effects You want to know what you're treating the worst thing we get here is someone's seen by a guy in the community They have what sounds like temporal arthritis. They give them 40 of prednisone First of all 40 in a in a good-sized man is not enough to treat it anyway And then you know, they come back again two months later with side effects from the steroid and say well Did they have it or didn't they That's always stuff to do so know your diagnosis at first because we get a lot of negative biopsies here because we're a Tertiary referral center so we often get you know, kind of the final dumping ground here So we end up doing a lot of biopsies that are negative now in a pathology practice They say you should have about 20 to 30 percent of your biopsies should be negative meaning that you don't miss any You're doing a little bit too too much in our Lab it's more like 90 to 95 negative and so we just get a ton of You know final referrals could this be so we actually don't see as many positives And this is that so-called healed arthritis So here's the lumen Intima Kind of thick and hard to see an internal elastic lamina. Here's muscular media here. Look muscular media kind of absent there No inflammation though. So this would be the so-called healed arthritis. So really know your diagnosis first Vice, what are we seeing here? so, um this field the optic nerve the This also could be From an ischemic cause ischemic optic neuropathy non-eridic Okay, so you could think of ischemic optic neuropathy, but you look carefully. It's kind of fuzzy here But wait, maybe that's a little bit of powder there. So I don't know Okay, now we'll we'll help you out a little bit with the diagnosis. This person's 20 Exactly. So one of the things could help you is age I mean, obviously if someone comes in with a funny disc in their 70 You're going to think more ai on if someone comes in with a funny disc and they're 20 You're going to be thinking more like an optic neuritis And so this turns out to be More an optic neuritis. And so you can see right here Unfortunately, this nerve has been wiped out here And so you can get but segmental focal areas here. It's okay here. It's been wiped out Now again, this starts getting really confusing here. This is just What do you think about this one, Kevin? So it looks like kind of the whole peripheral part of the disc is just kind of Spull and I can see that the vessels kind of come over like this type of raised portion and so And then it's kind of just all the way around. So I would think more of like an optic So you could think again and depending on their age kind of the same idea that we talked about Ischemic optic neuropathy, maybe even you know Area of inflammation, optic neuritis And so this actually turned out to be this patient had had MS and this was optic Neuritis and you can see here There's a focal area in the optic nerve of demyelination And so you often don't get diffuse demyelination of the entire nerve. You'll get focal areas So you can see this has got this one Kind of quadrant Has been affected by the demyelinating process This just shows you in a longitudinal view Here is an optic nerve sagittal here right here Again, it's a focal area With demyelination affecting the nerves and now Optic neuropathy, especially if it's associated with MS is a waxing and waning entity So you can get episodes where you'll get an acute episode and then it'll be calm for years and then you'll get another episode And so when you guys do neuro ophthalmology You'll learn a lot about optic neuropathy and the various studies that have been done and how you treat it And so you really need to know those cold But bottom line is is they did a very interesting study. They compared IV corticosteroids to oral steroids to just follow up And it turned out that the IV, you know, you blast them for three days with IV corticosteroids high dose followed by oral Actually the vision comes back quicker And the patients do better, but when you look at them at six months It makes no difference in terms of their acuity at six months But you know, again, if you have visual loss, you'd want to have it come back quicker But one of the things that came out of this study is they find out when you blast them with those IV steroids Their chance of getting MS Is certainly delayed for at least a couple of years. It may not be Cured and so one of the advantages too is it delays the onset of MS And so there's actually benefit to blasting them with those high dose steroids, whatever that does IV steroids But it turned out if you just treat them with oral steroids, they not only don't do better. They actually do worse So when these people come in three days of IV steroids followed by oral steroids followed by a taper And this is what you worry about in any disease affecting the optic nerve either ischemic or inflammatory What do we see in here? I mean, we see like total loss of Also, it looks like just total loss of infarction of the optic nerve and we see like edema as well In the subarachnoid space that believe it or not that is not edema. That's just Wide meaning of the subarachnoid space and so this is optic atrophy And so this is the nerve sheath and that subarachnoid space is really wide So whenever you get loss of the optic nerve fibers of those axons, you get wide meaning of that And so this is just end stage. So this is an atrophic optic nerve All right, and he gets Keep going just tell me what you see so looks like the Left pupil is larger than the right pupil. It's probably because the pupil's bigger Now it's a little bit displaced What direction is that I displaced? superior nasal If you look at the light reflex, it's actually a little bit inferior. So it's displaced a little bit inferior What do you make of the upper lip? Some ptosis maybe even a little bit of Fulness in there. So if you look I mean, this is a youngster. She's I think she's like 11 or 12 So what could be going on, you know unilateral in an 11 or 12 year old in a Again, you got to start thinking what are we lecturing about today? What's our topic? Okay, so what could be going on that could give you this set of symptoms? Intervation to the Extracular muscles and innovation to the to lid and then so when you see an eye that's kind of sticking Out and maybe you've got a little fullness here as if there's a mass behind it That's what this all shows. And so this is consistent with a mass behind the eye And then we look inside and we see this Jesus, what is this? So we see in here That's not a Yeah, those are those are posterior Striations those are little we call them wrinkles or folds almost And so now of course people are used to always get excited They used to teach, you know us in the olden days that this meant there's a lesion You know behind the eye specifically in the muscle cone when you see these striations But it doesn't necessarily mean that and someone who's hyperopic With a flat posterior surface of the eye you can get the same thing But this is actually that kit And so when you see these striations in the setting of proptosis and other things this is a sign that you want to look for A lesion in the muscle cone behind the eye and now this is what happens in the end stage of this lesion Look at that nerve That's a pale Atrophic optic nerve And that's because This is what the scan shows So what are we seeing right here? Yes, a large mass in the muscle cone. It's kind of fusiform So given the history and the findings of that previous patient, what would you be concerned about here? Okay, given the history that we said before Glioma, all right, so, you know, if you look in in kids and in adolescents teenagers You know lesions of the optic nerve in this area. Those are optic nerve gliomas In older people, they are usually meningiomas Now if you get one that's outside that group that it's it's really behaves totally differently And so people usually say well, these are kind of benign. They may not be aggressive Well, if you see a glioma in a 70 year old, that's a different animal But you know in a younger person you see this fusiform Lesion, it's almost like it's not around the nerve. It's almost like it's in the nerve And so this is an optic nerve glioma And here's is that biopsy Here's the nerve sheath. Here's the tumor within that optic nerve And here you can see this is one where they actually move the eye This tumor is growing out from the nerve and it's kind of a sausage-like growth or a fusiform growth Okay, so Oh, you can take a stab if you want. How do we grade these? And if you know if you say I have no clue, that's okay Okay, no, no, that's fine. I'll just take a stab because We typically grade these grade one to four Um, so what grade are most of the ones of the optic nerve? Yeah, exactly. So so when you think about these, these are astrocytonis And so the worst astrocytonic grade four is the glialblastoma Multiforme that's in you know, what the brain tumors, those are really nasty But these are grade one astrocytonis. And in fact people call these juvenile Pylosidic Astrocytonis juvenile obviously because they're in younger people. What does pylosidic mean? Hair like so they've got these little almost like little hair fibers in them, but they're low grade You don't see mitotic figures in them. You don't see a lot of pleomorphism. They're very very low grade Some people would even say they're almost like a hematoma kind of a benign growth But if you look at these oftentimes especially if they go back Through the optic canal, you'll even see remodeling of the bone in the canal, which means that these have been there for a long time And so this is kind of hair like pylosidic And here you can see them again. These are believe it or not astrocytes Some of them will be kind of spindly shaped. Some of them will be round And they have a specific Entity that goes along with them that you can recognize that you have to know Catherine What is this showing you? It's a rosenthal fiber. What the heck's a rosenthal fiber? It's kind of a bunch of degenerative material that's in the cytoplasm of these cells And so it's this pink Intracytoplasmic inclusion material here. It's called rosenthal fiber And that's classic with these grade one astrocytomas these optic nerve, you know pylosidically almost Now here's one That you can see it's growing up from the optic nerve. It's even squeezing the optic nerve So, you know, you can see how this is not really conducive to sight the problem with the treatment of these is okay You can go in and remove them Okay, then the eye's blind or you can just watch the tumor grow and then the eye's blind Or you can radiate them. These are really slow-growing tumors. They don't respond real well to radiation. And so You're kind of darned if you do and aren't if you don't The one thing we do worry about is sometimes you can get reactive meninges On the outside surface of a glioma and so there might be someone something's atypical their age range is different The orbital guys go in there and do a little superficial biopsy And they'll take a biopsy of one of these and then if you get this on a biopsy say, oh my god, that's a meningioma No, it's the actual surface of the glioma Down here where you get reactive changes of the meninges And so a bottom line is if you're going to do a biopsy And you know boopy and these guys are really good at doing that. Don't just get the surface go into the prank. I'm out to be sure here again Almost looks like a meningioma right here reactive proliferation of the meninges All right, Tina, what do we see in here other picture, but a different age group. So looks like that eye There's some inferior scleral show you get the idea that that eye is proptotic There's fullness in the orbits purely and inferiorly. So just kind of looks like everything's being pushed forward Okay So you're worried about a nerve, you know, you're worried about something behind that nerve again pushing forward now Look inside and what do we see in here? Optosilary shut vessel Optosilary shut so I mean these can show up in central vein occlusions and other things but in this setting Why would you get an optosilary shut? anything that is Compromising Nervous culture. So like a meningioma would give you Exactly. So I mean if again, what are we talking about? We're talking about optic nerves. We're talking about an older person So likely this is a meningioma meningiomas again, they go from the meninges not from the Inside of the nerve but from around the nerve. So they slowly Squeeze off and strangle the nerve And so as that slow process is going on oftentimes you'll get these little optosilary shunt vessels forming to try to get You know blood out of the eye and then through that nerve from where it's being squeezed down and strangled And so this is the classic appearance. What do we call this? The tram track sign so you can actually see the nerve Still there and then you see the widening of the meninges next to it So kind of like the you know tram going up, you know with the tracks around it, you know the tram wire So they call this the tram track sign This shows you a severe example. This actually is an exenteration, you know or remove the whole Eye and orbital contents. Here's a little bit of nerve here and here's this huge tumor Bilob growing up from the meninges behind the globe All right, so vice what do the cells look like? Um, so these are from the meningosilial cells. They look they have a pink or cytoplasm look kind of like squamous cells Exactly. So they almost look like squamous cells, you know, they've got this nucleus notice the nuclei the clump chromatin But the pink cytoplasm and they tend to form these little worlds almost almost like squamous cells do And you can see if you look at this people say kind of that kind of looks like squamous cells almost What are these things Caleb? Is your somoma bodies? Somoma bodies First of all spell it Good so somoma with ps Somoma bodies So again, these are almost like if you think of drusen these are almost like Um concentric lamellar structures. They've got hyalin in them. Sometimes they have calcium in them They almost look like remember when squamous cells form those little squamous pearls It's kind of the same idea here. And so these are called somoma bodies and there's the meningothelial cells And there's the somoma bodies. So these are a real classic tip off that this is a meningioma All right, what else can show up in the muscle cone back there? So you could have a um What are the kind of cells live was the optic nerve goes back astrocytoma? No, that's the lioma. Yeah, um Schwannoma Schwannoma exactly remember Schwann cells live back there So it's very rare, but you can get a schwannoma right next to the nerve It doesn't come off the nerve itself, but it's right next to the nerve. It's in the muscle cone You can get a schwannoma or what's the other proper word for schwannoma? I I didn't know what you're talking about. I have no idea Neurolemoma and again spell if you can spell that and somoma you guys are doing well because there's double m's in there So neurolemoma Uh, let's you know, this is an unfair question. That's a fair question for a For a second year here What are the two growth patterns you have to memorize for schwannoma neurolemoma? Exactly and which one is this one Okay, so see again. I'm ocd. I'm going to show it in order Yes So antony a Is a swirling or fascicular pattern. So if you look at these Schwann cells, they're almost spindly shaped and they form this little swirling fascicular pattern. So that's antony a And then antony b is a more mixoid It's almost like there's a little bit of fluid in it and some other background materials in there. So this is an antony b And antony is is like, you know, the only pathologist who wasn't like german or austrian or british, you know, I think he was Italian I think so in any event antony a is swirling fascicular antony b is more mixoid Okay, and then we say hi to the penguins at the zoo Next week. I hope it doesn't snow so I can get here on time Next week is orbit Okay questions on optic nerve