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To help uh guide your understanding. So firstly, can someone please confirm that you can see the screen? OK. May put it in the chats just to make sure that you guys can see it. OK? Yeah, we can see it. OK? Brilliant. Thank you. So, um OK, so firstly, actually there, there's a little disclaimer that this is made um by medical students for medical students. So this should help your learning but do not use this as a resource provided by um directly University of Sheffield. So, um the aims of the sessions are we are gonna try to un like e essentially unpick and understand the basic terminology that we use in neuroanatomy. We are gonna also try to identify general er features of um the brain and we're gonna try to talk about the meninges and what are the clinical relevance of them um specifically in terms of hemorrhage or stroke. Um We're also gonna talk about um blood supply of the brain and circle vus. Um And also if you're gonna like try to integrate some er multiple choice questions to er help you prepare for future exams as well. Um Also we'll try to er, talk about the ventricular system. Um, so it's quite hard to, er, visualize it in real life, but we'll try to talk about it. Why is it important? And the root, er, that's every spinal fluid takes. We're also gonna talk about um, the roles of each of those lobes of the brain, er, that they are commonly asked in exams as well. And we're gonna talk about the homonymous. So it's something that comes up in exams. It's actually good to know and to put all of there anatomy in clinical practice, we'll also focus on um some of the features um of the cranial fossa and um essentially what passes through those um bones and the structures as well. And we'll focus a little bit on um their bony orbits, um ears, eyes and er anatomy associated with those and also their nerve, um nerve nerve supply of those structures as well. Um Also we'll talk about uh some general basic clinical imaging as well that to help um facilitate that learning as well. So, um firstly, it's not commonly tested in exams but it's good to understand this to know where it comes from. So we have prosencephalon, mesencephalon, rhombencephalon, some people call encephalon, but either way is fine. Um So, prosencephalon is the forebrain. So it's the embryological origin. It will, these will divide further down as well and then become er, the forebrain. So, does anyone know what are the two structures that prosencephalon is gonna make. So mesencephalon is gonna make the midbrain rhombencephalon is gonna make metencephalon, which is gonna be your pons and your cerebellum and myelencephalon is gonna make a medulla. But prosencephalon, there's two structures that we're looking for. Anyone knows what the name of those are put in the chat. Ok. Absolutely fine. So, um, essentially, it's, it's a little bit hard, but essentially it's good to know, er, telencephalon or telencephalon and diencephalon are essentially the two parts of the brain. So, diencephalon is just the central part. Um and then the rest is just gonna be made by telencephalon provided here. So, um essentially you need to understand the general features er, of the brain as well. Um So we have Gyri and Sulci that's, they're essentially the basics. So gyri is gonna be that um essentially bridge, but Sulcus is gonna be the depressions that you get in the brain. Um You, you might not be able to appreciate these so much um on, for example, an X ray or CT scans, but essentially they are quite key to understand and their functions. Um So we have different lobes as well. So the four lobes of brains are the basics, er, you need to understand the functions that could easily come up as a multiple choice question um or as a short answer question. So we have the frontal lobe, er, there are lots of personality. Um motor is there paal lobe, there's behind it we have temporal lobe and an occipital lobe at er the back as well. So you might actually er hear about insular and opercula as well. So insula is essentially um like if you think about temporal lobe and frontal lobe, there is um line there that divides them that I'm gonna ask you about that. But if you go deep in there, there is gonna be um essentially a part of the cortex that we call it the insular. So you don't really need to know what its functions are. Um if you're at like early years in medical school, er but you need to understand that they do exist. So opercula is just gonna be that lid around it. So that part of temporal frontal lobe that covers it. So um if we talk about it, um we've got two big sulcus. So sulci that actually divide the brain and are quite easy to find. So I've named the first one. Number one, does anyone know what that one is? Absolutely. Yeah, a spot on. So that is a central tors, a spot on. Um good. So what is number two? So number two is dividing temporal lobe from frontal lobe and paal lobe. Any ideas? So we talked about that one being central. What is the other one? Is it central? Is it lateral? So it is essentially the lateral sulcus, the spot on molly. Good. So um yeah, absolutely. So these are key to understand but they're quite easy to find why because if you put your finger in, in, um, and essentially the anatomy room, you will be able to see that actually, your finger can go deeper inside these sulci compared to the rest. So there is some other sulci. So there's a para, para to occipital fissure at the end that divides those, you don't really need to know much about them because they're harder to find. Er, but these are the basics. So if you talk about er, the brain on the right hand side, this, that is a sagittal section that you can see there. Er, we've got the cerebrum, we've got the diencephalon there that shows the hypothalamus, pituitary glands, but we also have cerebellum midbrain pons medulla. So you guys are gonna go through this in Sheffield later on. Um er, but also it's good to appreciate these at this stage as well. Um Sorry, apologies. I'm gonna share my screen again. So, yeah, absolutely. So, um ever anyone knows the name of the sulcus that is in occipital lobe? So it's a common sulcus that is there and we usually refer it to as er the place where visual um data is gonna be processed. Anyone knows what that's called, that's a little bit harder, but it could come up in exam questions because it is a quite famous one. It starts with C no, what? Absolutely fine. So, calcium sulcus is what I was looking for. Um So essentially it has come up in shift exams before I believe. But they don't really elaborate on it too much because you just need to know if a lo is related to that. So, Corpus Callosum, you hear that a lot um And you hear that it is a commissural fiber. Well, you might actually wonder what is that? So, a commissural fiber is a like type of fiber that will allow you to transmit the information from one side of the brain to the other side. So from left to right or right to L to right to left. So actually, you might have heard that the right side of your body controls the um like is controlled by the left side of your brain. And corpus callosum is part of the reason why because it could cross through there. Um There's two other projections as well that you need to, you guys need to understand. Um those two fibers are called association and projection fibers. Um Essentially, you just need to know what these are. They don't expect you to know names and these two are a lot lower yield than corpus skeleton. So Corbo Keum is commonly in exams fiber, but does anyone know whether an association fiber or a projection fiber is or what do they do essentially or any examples you can give either way is absolutely fine. OK. Absolutely fine. So association fibers um wait, we've got an answer. So fibers in the same lobe as spot on. So they are fibers in the same lobe, good thinking. So association fibers, as we said is just gonna connect er different pathways in the same lobe projection fiber is slightly different that it's not connecting in the same lobe. It's taking from that lobe. It is still in the same lobe as you said, but it like it transfers it down essentially so it can uh transmit it to the midbrain pons, medulla, et cetera. Good stuff. So, this is the inferior view of the brain. Um er er this is essentially a lot easier than what you would see in an actual brain. Er, but it's essentially er good to understand these er, the structures. So, er, you might actually hear a lot about midbrain pons medulla. Um they're quite easy to find, but we've got something called Crus Serere as well, which are essentially um coming from the, the pons and they're going back to uh the cerebrum. So, uh the, the reason they're called cerebri is because they go to the cerebrum. If they were cerebella, it means they were going to cerebellum. So you will hear more about um attachments of the brain stem to cerebellum later on. Er, but there's some ob some actually er, structures that people find sometimes hard to understand. So I've named them 123 and four. So the, the, the, the way I used to remember it was pituitary gland is one we don't have two of it, but we do have two mammillary bodies. So, which one do you guys think is number one, a spot on that is, er, pituitary gland? Indeed. What about number two? So I assume everyone's gonna say um mammary mammillary bodies spot on as well. Um What about number three? So it is one of kind of, some people call it an extension of cerebrum. So, um it's usually not considered to be a peripheral nerve and it's not gonna be the optic nerve because we, we can see the optic nerve is close to the pituitary. So, what nerve do you guys think that would be, it's spot on? So, a factory nerve is absolutely right. So, yeah, absolutely. So, a factory nerve would be there. What about number four? So number four is a structure that is essentially, um, in, in this case, we're looking at it from an inferior perspective. So it would be a little bit superior. So it would be at the middle of the brain, um, a little bit above the pituitary gland, maybe it, it supports the pit pituitary gland as well. What do you guys think that structure is called? Any ideas? Yeah. Spot on hypothalamus is absolutely right. So, um, hypothalamus is exactly, er, there and it essentially controls some of the hormone secretion to pituitary as well. Um, so you might actually wonder what mammillary bodies are. So, essentially, er, they are part of the pet C cycle. So they do some of the stuff related to memory. You do not, I don't need to understand the details of the pathophysiology, like pathophysiology later on, but the physiology of what they exactly do at this stage, so just know they exist. So in terms of the lobes as well, you just need to understand that these lobes exist and what do they do? Um So in terms of frontal lobe that we discussed what they do have um like essentially after that central sulcus, um we have something called a pre um essentially central gyrus or soar and that's where your primary motor cortex is gonna be. So it's called precent because it's before the central. So, so what you have there essentially controlling your motor well, before that you have a premotor cortex as well that it will help you to plan those that you're gonna ex execute using your primary motor cortex. Also, frontal lobe er is gonna be associated with a lot of things like problem solving, personality behavior, sexual behavior, et cetera. And we have Brocker area as well that is involved in a spoken language production. So it comes up quite often in exams. What area is um responsible for spoken language production, not understanding paal lobe that we discussed as well is a little bit behind it. So a lot of what it does is essentially understanding the sensory information that goes into the brain. So you have the primary somatosensory cortex right behind it and the secondary somatic sensory cortex behind it as well that they er process the sensory information. We have um essentially other stuff in that lobe as well. So er the left, the left lobe, like the left side of your brain is gonna control perception, mathematical and language operation as well. But the other side of your brain is usually non dominant, which is usually right like side of the brain um is essentially important for visuospatial function. So essentially um 3d er things how you process that et cetera. Um So in terms of temporal lobe as well, er it's a little bit behind the lateral, not behind um this inferior to the lateral sulcus. And what you do get is a primary auditory cortex. So essentially responsible for um hearing and at at very essentially posteriorly to it and superior to it, you will get the Wernicke's area which is responsible for language understanding. So another very common exam question. So this is all you need to know for temporal lobe but also temporal lobe. If you go a little bit medial towards the brain, like towards the center of the brain, you will see other structures like hippocampus, er basal ganglia. So those are a lot more involved in um essentially memory formation um and er sometimes um motor movement as well. But if you go down to occipital lobe at the back, we talked about calcium sulcus and that's the area where you're gonna essentially have your primary visual cortex and then understand um vi visual information. But also you have something called the limbic system. You don't need to know like too detail about what exactly everything does. But you need to know that there are amygdala hippocampus, these are structures that are involved in emotion er memory behavior. So this is a little bit information heavy but actually understanding this helps you to unpack a lot more er further down as well. So I think I've shown you guys the answers. So notice Rocker's area is gonna be your frontal low Wernicke's area is gonna be in your temple road as it's gonna be poster. So let's put it in some practice. So now imagine you've got your friend who comes to your clinic and the memory formation has been affected and they seem to struggle to remember many of their memories, which of the lobes of the brain is most likely affected. So we talked about this as a limbic system, hippocampus, which lobe of the brain are those located in? So always try to unpack the question. It has a clinical stem. You don't really need to understand what retrograde or anterograde um memory loss are. You just need to understand where those structures are? What lo they're located in? Good. Uh Thanks, thanks, good. You're absolutely right. So brilliant. So it is a temporal lobe. We talked about it. Hippocampus is essentially like very involved in secondary memory formation and um like loads of d structures in the limbic system, they are actually in the temporal lobe. So it is most likely to be affected. So you could argue that the other lobes could be affected by an S VA. Just remember you're choosing the best answer. Good job. So homonal, you might have heard of it. So essentially if you talk about the motor cortex and the somatosensory cortex, you could map all of your body into a region of that cortex and you could use that in clinical practice. So you could see you don't need to remember every single detail of this. What you do need to remember from this is that legs are the medial side of the brain, your mouth, tongue face are gonna be lateral side, your torso of the body and your hands are gonna be um towards the superior side of the cortex. Um You might think, why is that important? Because you will understand the arterial supply to these regions. And if you, for example, see your leg being affected, you will be able to link it back to which arteries most likely to be affected and it can target your treatments through that. So let's look at the bro blood supply there as well. So middle cerebral artery, anterior cerebral artery and posterior cerebral artery from circle villous. So, posterior cerebral artery mainly supplies um the occipital lobe. So you can see is involved with vision. So if someone's vision is affected in a stroke, think of that the middle cerebral artery uh essentially supplies the bulk of your brain, the majority part of it, but it doesn't supply the medial aspect of your brain. Um So if you see someone's whose leg has been affected, you should think about the anterior cerebral artery because that's where it supplies it. But if they mo the mouth tongue, facial expressions are affected, maybe think about the middle cerebral artery. So we are gonna talk about uh the blood supply in more detail. Uh story about it now, but let's think about a patient. So a patient comes in and they have an anterior cerebral artery in infarct. So which part of their body will be affected the most? So this is actually a very common question they ask year on year, they just put it in a she exam. So I think, but it could even if it doesn't come up, it's a good learning er point. Er what you can do is try to map these areas on the homonal to where the arterial supply is. So any any responses you have, so which which parts of the body would be affected the most? Absolutely, I agree. Er lower limb would be affected as spot on everyone. So um as you can map it, so that's what it could be. So, again, very common question. So if you move on to meninges, um you essentially, you will hear about pia mater, er, arachnoid mater and essentially dura. So you just need to be able to acknowledge what they are. So pia sticks superficially, you will not be able to recognize it cos it's just a layer of the brain. Um Arachnoid is just gonna look like, er, weber structure is just like kind of like cling film attached to the brain whilst dura is gonna be very hard and it's not really attached to the surface of the brains a little bit er further. Um and it's very tough. So that's how you can distinguish them. But also very common question that comes up in a short answer question is a four marker or 23 markers. It could be understanding the fact that pia actually fuses with those endothelial cells of the brain and forms the blood of brain barrier. And that barrier has a specific features that makes brain such a preserver structure. So the four things you need to know that endothelial cells are actually tightly bound. The basement membranes actually lack fenestrations. And we have parasites and astrocytes that wrap around those capillaries, restricting the blood flow. So actually they will minimize the harm that could be delivered or potential toxic material that could go from the blood um to the brain. And we have the a meter as well, which is essentially um the relevance of it is the subarachnoid space. So which is between the Arachnoid and the pia and where the spinal fluid is majority of it is gonna be located. So remember that as well. So in terms of sinuses are not the most high yield thing. There's some of them are more important than the other ones. Er, but essentially they come because of the fact that they, er, lie around where your um, essentially mening GS er, tend to split or th th like they tend to fold er on themselves. So, understanding dura can help you with that. So, Dura M essentially has two layers. Does anyone know what those two layers are? Anyone knows any ideas? What would the two layers of do Robbie? I'll give you a hint. One of them is inner, one of them is outer. Does that ring a bell? No, absolutely fine. So we have the outer endosteal layer which is attached to the skull and we have the inner meningeal layer which is attached to like brain essentially. Um So in terms of where those sinuses are gonna be there is the sinuses that are gonna be there as well. So we have the superior and inferior sagittal sinus, which they're gonna run exactly where I'm pointing at. Um essentially at the top of your head. And er inferior sagittal sinus is just gonna be around your corpus callosum and inferior sagittal sinus is gonna have the straight sinus. It's gonna drain the straight sinus and go conjunct uh essentially have a conjugation and meet the superior sagittal sinus at confluence of sinuses at here at the back. Um But also remember that not, not all of the, these are too important. I would say the most important ones are probably the fact that transverse sinus comes from confluence of sinus, it goes to sigmoid sinus and it goes to um essentially internal jugular vein. So this is essentially if I want to memorize one thing, I would memorize this pathway of going out because it is more commonly tested. So, unless all party in terms of a case as well. So, er, we've got John who is a 24 year, 25 year old male and he was er, involved in a motorbike accident and he was initially alert with mild headache and he was stable. His Glasgow coma scale is 15 out of 15, which is really good. But after an hour it drop, drops to tw te 10 out of 15, which means er, his conscious level is going down, he feels drowsy, he feels he's got headache, he's got nausea. His pupil is dilated and he's not responsive any ideas. What does we, we do act scan and what does the CT scan show? So can you, can you even if you don't know the exact condition, can you tell me describe this to me? What can you see on the CT scan? So you do not need to be a radiologist. You might actually see this in A&E er, I mean, it might not be as severe as this one. but it could be, um, so it is good and useful for everyone. So, what can you guys see on this x-ray? I mean, the CTI would say, but yeah, what can you see on this? Any ideas? A spot on? Er, so a spot on, you've gone like 10 steps ahead. Got the, like, essentially diagnosis, right? So it is extra hemorrhage. But even if you're ever trying to describe something and you're not sure how er what to essentially say, just think about the basics. So think about the colors. So um if you have something that is white is suggesting that you might have a high density at that, at that place that uh than you might have usually had um someone suggested absolute brilliant. So midline shift. So that is something that you classically see because the blood accumulates in the space. It shouldn't be, it pushes the brain and it causes that shift. So spot on. So these are the common features as you guys describe. Er why do you guys think that we didn't go for an X ray? So I mentioned an x-ray, we've gone for act scan here. Why do you think an X ray might have not been as useful as this one? Is an X ray gonna show you much? Is it gonna penetrate through the skull? The spot on it shows bones good thinking. So you're actually not gonna be able to see much of the brain. You er it is useful if you wanted to look at fractures, like um maxillofacial fractures um and visualizing those, it will be really useful but not in this scenario. So it's what on, so differentials could be the different types of hemorrhage. But as we've seen based on the structure, we can say is extradural. So these are the different types of hemorrhage, you will see them often um not often in medical practice, but you will, I mean, depending on where you work, you will see them. And so we have extradural, subdural and subarachnoid that are very common. So you might actually wonder why are these like the like the pattern that you can see here because extradural imaging is between your dura and um your skull. So what is happening there is dura doesn't stretch, it's very fibrous tough. So as you can see, it will make this like this shape because it doesn't have a way to actually spread around there or there because the dura doesn't allow it. But subdural is because it's below dura, it can actually spread because it doesn't have that resistance anymore. And so Arachnoid is essentially just internal. So it could be at any place, it doesn't need to be just laterally er located. So let's talk about the secular villous as well. Um So essentially you just need to use one of those things that you need to memorize and not everything is in like too high yield on it. So, po po pontine arteries and er basal artery might not actually come up as often. Er or for example, anterior inferior cerebral arteries, superior cerebellar artery do. One might not commonly be asked to identify but they are good to know. So um 11 of them that I actually gets commonly asked is about anterior communicating branch, which is um essentially between two arteries that I'm gonna ask you about. And you need to understand the posterior communicating artery as well. And this shows an anastomosis. What does that mean? It means that we've got different parts of the brain supplying the same areas. So if one gets occluded, you, you can actually supply them by the different areas. So it's actually a uh evolutionary thing that will help us. So um let's talk about what number 123 and four are. So what is number one? Does anyone know what number one is to what artery is that representing? So we can see the internal carotid arteries coming in, we can see um that it is branching and it's giving a big branch and it's giving you a smaller branch. So a smaller branch is gonna be number one, which one would that be? And it's anterior as well. So this is the anterior area, this is the posterior in uh area. So what would you call this artery? It's anterior, it supplies your brain any ideas? Absolutely brilliant. Thank you, Molly. So, um spot on anterior cerebral artery is what it is. So, number two, therefore, it is gonna be middle cerebral artery because of the fact that it comes directly from internal carotid and it's a big branch and you can see it's a lot thicker because it supplies as we talked about most of the brain. What about the posterior one? What would you call that one? What do you think? Number three, posterior cerebral, thank you, spot on. So, um absolutely, that would be the posterior cerebral artery. And before that, behind that, right, er before that, you will see the superior cerebellar artery. So essentially it supply of the cerebellum, it comes from the basal artery and we have the anterior inferior as well because they are both of them are um there. But superior cerebellar is anatomically a little bit superior, anterior inferior is a little bit inferior to cerebellar, but still anterior to the posterior inferior cerebellar artery if that makes sense. But you just need to know that they exist mainly and they apply to cerebellum. So, what about number four? What is that one that is coming from the vertebra and it's coming up and it's supplying your brain, what would be called that artery? A spot on? That's vertebral artery. Does anyone know where it comes from? Sometimes it comes up in exams. So it's good to know what artery would actually er branch to give, er, vertebral artery is from here. I don't know if you guys can see me but um is from right below your neck. Subclavian is spot on, er, after you guys are on fire. So good. Um, good job guys. So you just need to know where they supply as well as we talked about. So let's put it in practice. So now you've got a patient who's admitted to a stroke ward. He has examined uh actually, he was examined and we found that he had a motor leg, score of three out of 10 for his right leg and a score of eight out of 10 for his left leg, which artery is most likely to be affected. A very common exam question. Um What do you think is gonna affect it? Bear in mind that the right side of your brain controls the left side of your body. So that's the trick here and also try to map it to the homonal. What do you guys think is gonna be affected ABC or D? OK. B you've got a vote for B anyone else? Ok. Thanks for you're absolutely right. So it is left anterior cerebral artery. We talked about this as the anterior cerebral artery is gonna supply the medial side of your brain and that's where the homonal your leg is gonna be. And as we talked about the right side is su su er essentially processed in the left side of your brain. So left side of er the anterior cerebral artery is gonna be affected, good job. Um So we'll do a quick, a quick case. You can guys can just have a look at this. So you can see a patient came in and they had a sudden right sided weakness. So as you can see the left side of your brain is affected and they had a slur of speech. Um So you can see probably something to do with this area. The lateral side there, your tongue, your speech are gonna be is gonna be affected. Um And essentially, they have some really big risk factors of hypertension hyperlipidemia. And er essentially right side, the hemiparesis means like loss of motor function on the right side. And we have done a CT scan and we have seen this anomaly here. What do you guys think this is gonna be? So, what is this, what artery do you guys think this is ao clear? So based on they would, they would not ask you, I mean, they could but er they would make it obvious um about what it would be, but it's good to actually try to er visualize based on what the patient presents and the data that you gather and try to come up with a differential. So spot on in one spot on. So um essentially middle cerebral artery is gonna be affected because that's where the bronchial verities area are gonna be located, et cetera. So we can give them some er, tissue plasma as an activator, which is the thrombolytic to be able to help our patient and we can assess them further with ct perfusion perhaps and talk about a thrombectomy and the different options that we have available based on severity. So, let's discuss the cerebrospinal fluid as well. So, er, it is commonly asked, er, it's quite hard to visualize it's the center of the brain but try to think of it as this way. What, what I've tried to put here is a picture that shows where it is exactly lo located and you need to know the pathway. So we have something called choric plexus. It is gonna be lateral ventricle, cerebrospinal fluid that starts, there goes down the interventricular foramen, sometimes people called from of Monro. So that's the, all the name just memorize one that you like. Then it goes to the third ventricle, which is this big one here and then it goes via the cerebral aqueduct to your fourth ventricle, which is gonna be exactly anterior to your cerebellum. And then you are gonna get central canal that goes to uh your spine or you're gonna get median aperture of Madi or a lateral a aperture of LUSA. So how the VE I used to remember it was lateral and lusher median and magen. But again, it's not the most high yield thing that could come up. So I've already discussed what these are but can someone tell me what is the function of Chop Plexus? It could easily be um short answer question, one mark. Anyone knows what, what, what it does. So, absolutely. Spot on er good job. So Choric Plexus does er produce your crespin fluid. So it, its function just memorize that. Um Good. So let's move on to the fossa. So we have the anterior posterior and er one other fossa that I'm not gonna tell you guys, which is not a spoil it at all. But what is one? So which one do you guys think is one? Number one, what fossa would that be a spot on? So one would be anterior cranial fossa, what would be number two then, so if one was anterior, what would be a spot on? So two would be posterior and three would be middle. So essentially, it is quite self explanatory. Most things are an anatomy. So you can relate them to er what makes sense of it. So this is the most common exam thing that you could get if you wanted to take one thing out of this session, just just know these ones, I appreciate. These are quite hard, but you need to understand where do structures come out of the brain and specifically the cranial nerves and the anterior cranial fossa. Uh it's essentially gonna be this area here and er you can memorize what bones there are. So there are er like bony orbits, er why because it's just the, where the orbits are, it's just superior to that. We have got the cri form plate here and a Crista Galli at the top of it, which is the, just the bony ridge. So, c form plate know it, er, is quite common in exam. So, transmits olfactory tract. So if you come a little bit lower down, er, we, we'll be able to get to middle cranial fossa. So we have that essentially they're greater and the body er of eso bones. So senno bone is just gonna be where your eso sinuses. Um and then you have your petros and a squamous part of the temporal bone. Um essentially petrous is the hard part that's here. The squamous is the soft part that is there. Don't these are not the most high yield, what is high yield is those fissure? So we have optical canal, which is here, which is gonna be where your optic nerve goes through. You have the superior orbital fissure, which is gonna be here, which is gonna be where a lot of the nerves that supply your eye, which are not the optical nerve. So the ones that supply the eye muscles are gonna go through er which are gonna be abducens trochlea and oculomotor, then we have Forman rotundum, which is quite smaller than oval. So for ovale is gonna be mandibular branch of your er maxillary nerve and like trigeminal nerve. Sorry. So you might think why is it bigger? Because the mandibular branch has motor function and er, the maxillary branch which goes through for and rotundum dot So it's actually not as thick as um, the mandibular branch. So it's quite smaller. And then we have, er, here what is called the, um, essentially foreman last one. And that's where your, er, carotid artery is gonna go, go through and then you have, er, for and magnum, which is the big one and you have er other ones that are in posterior er cranial fossa, like your jugular Forman um and internal auditory meatus as well where your vestibular cochlear and your facial nerve are gonna pass through. So I think you guys have it done cranial nerves now. So do not worry about oh what the functions, all, all of these, you will do them er, with the cranial nerves, but it's just good to know. Er, it's commonly asked in exams. So just make sure you remember them. So, jugular from internal aus and hypoglossal canal are very commonly asked as well. Jugular Forman because it is vagus, accessory nerves and internal jugular veins. So there are quite a lot of important things that pass through that. Er, but yeah, let's move on to some ocular massage as well. So you need to understand one thing that if you wanna remember the most important thing is the nervous supply to things, then the arterial supply, then the venous supply, then lymphatics. So venous supply and lymphatics nearly don't come up. But nerves are always something that examiners love. So you might have heard this lateral erectus is supplied with cranial nerve. Six, superior oblique is er via cranial nerve. Four. The rest are gonna be supplied by cranial nerve three. So I'm gonna talk a little bit more about these. So don't worry about them now, but let's get these definitions set. So elevation means looking up, depression means looking down, abduction means looking medially, abduction means looking laterally, extorsion means rotating uh your eye. So the top of your eye goes laterally and intrusion means the top of your eye goes immediately. Um So essentially, you need to understand these to be able to explain what the muscles do. So you have levator palpebra, superioris, superior rectus, inferior rectus, medial rectus, lateral lus and so on. So the most easy ones to remember are the rectus ones. They do exactly what what they sound like. Superior rectus, elevates, inferior reus, depress medial rectus abduct, adopt means brings it towards medial side. Lateral directus pulls it out and abducts it. Um the the the way another way that I used to remember the the nerves that supplied in is lateral rectus abducts, abducts, abducens nerve, essentially, that's another way. Um Superior oblique is the odd one that is supplied. Uh and it is gonna be innervated by your tral Nove and superior oblique and inferior oblique are just gonna be a little bit different. Why? Because if you look at it, they come from the lateral side, they pull the eye from this angle to there. So actually because of the angle that they have, they are essentially er firstly in toting. So they're causing er the top side of your eye to go media, but also they will cause the your eye to essentially depress based on the angle that they have. Er so they actually do the opposite. So superior oblique doesn't elevate it just depresses. Um So another common way to test for them is er because they all do the same function, not all of them, but like superior rectus and inferior oblique, both of them depress. How do we test for them? If you essentially adopt your eye, you are getting a superior rectus to adopt it and then you put it in a position that the only um muscle that will be able to um elevate your eye is gonna be inferior oblique. And if er you can't elevate your eye in that position, inferior oblique is gonna be affected. So just, just try to remember this. But if it doesn't make sense guys, just let me know. So, er accommodation and pupillary dilation and constrictions are important, you don't need to know exactly all about them. The main important thing is that they are supplied by the parasympathetic fibers of the ocular motor nerve common exam question. So know the fact that ocular motor nerve has parasympathetic fibers and it causes um, essentially your ciliary muscles to er, contract and also, er, affects your, er, pupillar as well. So, we have constricted pupillar and dil pupilla that, that are the muscles that dilate and constrict your eye as well. So, another thing to understand is the pupillary er, reflex. So essentially the light reflex. So what happens here is, um, light enters your eye, goes to your retina, optic nerve picks it up, goes to your brain synapses at a nuclei, which is quite commonly asked in exam as well. Does anyone know what that nuclei is called? What do we call that nuclei? That the optic nerve goes and synapses there. Anyone knows any ideas? So it's a little bit harder. It's, it's es es essentially they're adding your vs ball nucleus, nucleus or NUC nuclei because we've got two of them. Er So essentially it's gonna be er towards the center of your brain and it's where they synapse and it's a common exam question. And from there we get the efferent nerve, er which is the oculomotor nerve. So, efferent means I used to remember it e exit. So it comes out afferent is going in. So oculomotor that we talked about is the one that comes out where a parasympathetic nervous system and it constricts your pupil are of the iris as well. So that's essentially a reflex that helps you to reduce damage to your retina. And there is some connection between the right and left nuclei. And that's why like light will cause both of your eyes to close. So, another common exam question is asking about the sec er, like, er, secretions of er, the lacrimal glands. And it could ask you, what is the nerve that er innervates the lacrimal glands? So, it's gonna be the parasympathetic. Always remember, er, sec secretory glands are gonna be innervated, parasympathetically, activated, parasympathetically. Um, but what is that? What is the nerve that does that for the like more glands? Anyone knows, what do we call that? So, essentially think of which ones do have parasympathetic. We talked about oculomotor does facial nerve, does glossopharyngeal, does, does any of them, do you think would supply the area? No, no one that was absolutely fine. So it's gonna be your facial nerve. So just remember that. So it's cranial nerve, seven facial nerve is gonna innervate your lacma grands. So, last part before we go through more, um SBA S is just knowing about the basic structures of ear. So know that we have er, the outer inner and middle ear canals and what we do have in um essentially the middle ear is gonna be the three bones m malleus, incus and sts know them because they could commonly come up in an exam, ask you about it to name them. And er, the fact that we have the cochlear vestibular system at the inner ear and no, the main functions so do not get too bogged down on like the, the the niche details. But vestibular system has a semicircular canals, arts and saccules. So semicircular canals are where the fluid is and they are 3d, there's three of them and they essentially help with your balance, but we do have C er cycles and not as well. So you don't need to understand them in too much depth. You just need to know that they are involved in er linear acceleration actually knowing like and being able to er understand linear acceleration. So whatever it does, um we are gonna finish in time but I've put the certificates, er, feedback form there. So if anyone wants to leave early, feel free to do that, fill the certificate, make sure you do that, you get your certificates for your portfolios. But yeah, let's carry on. So, um essentially you need to understand the vestibulocochlear nerve is gonna be the nerve that innervates that, that could commonly be asked and um essentially know that the order of malleus and estates and know that there's two windows. We've got the round window and we've got the wa window and usually people mix them up in terms of, er, saps, which one does, er, saps actually connect to. Um, but yeah, so that's pretty much all of the basics you need to understand. You will have a lecture in Sheffield, er, on physiology of how um visible of like tympany and other things. Or Organ of Court in cochlear work, et cetera. But we're not gonna focus on that. So any questions so far, feel free to ask me. But II hope it all makes sense. We're gonna go through some more SBA S to actually show you guys what are the common things that they do ask from these two sessions. So imagine that we have a patient who has a severe headache, um and they have severe head injury and her skull was fractured. So they're asking you to identify the bone, the bone in the skull that actually was fractured, that is shown in the image here. So usually in exams, they don't want to tell you to identify this. They usually put like a stem for phase one medical since it's usually irrelevant. So you don't need to really understand what is going on. It just put some context into it. So do you guys think it's the squamous part of the temporal bone, petrous part? Uh is it the pari bone or is it the frontal bone? So we talked about what squamous and petrous. Are anyone knows any ideas? So think of it as is this the medial side or is it the lateral side? So it's probably not gonna be your anterior or posterior cranial fossa. So it's probably in the middle side and think of it as um is it gonna be the soft part or is it gonna be the hard part? Do you think, OK, I'll give you guys the answer for this one. This was the Squamous Box. So it's a little bit hard. What the reason for why I put this here is you guys usually get used to one specific type of picture that is in your anatomy handbook. It's absolutely fine. Cos that's what they usually test for. Er, but it's good to actually look at them from different perspectives. So this essentially, um, the lateral part is not the medial part. Uh So it's not gonna be the petrous part. So the petrous is the like essentially the medial part, which is quite hard er, that you'll be able to see probably around here. So good. So now we've got a patient who's admitted to A&E with a suspected stroke and his right eye is severely affected which lobe of the brain is most likely damaged. Ok. Thanks for us. So we've got uh one word for c anyone else thinks anything else different or anyone agrees. So your spot on that is left occipital. So we talked about occipital being at the back and what it does it it like essentially um gets a lot of the data from your eyes and visual um data goes there. So if you think about ever think of like see a patient and with the stroke, your eye is affected, think about occipital lobe. So another question would, could be which artery is affected. So that's gonna be the posterior cerebral artery. So it's what's on and the right side of the body is uh essentially processed by the left side of the brain. So that's why it's gonna be left occipital. Good job. Um So now we're asking you which nerve passes through this foramen that I've highlighted there. So again, one of those common questions which you will get used to it when you will do cranial nerves, what you will see here that we talk about these being the optical canal there, you will have a superior orbital fissure. This is gonna be one you're gonna have after that, if anyone remembers, I think of it as maybe the mandibular branch was too thick to go through that small aperture. So anyone has any guesses on what this could be? Guys, don't worry about getting it wrong. By the way, I get these questions are what you would expect be expected to know at the end of the year. So don't worry about it too much. Just give it a go what you think. Yeah, thanks for. So Maxillary branch of Trigeminal, anyone else agrees disagrees or you're shy. Yeah, absolutely. Fine. Brilliant. So it is the Foreman rotundum, which is gonna be the maxillary branch of the trigeminal nerve, er which as you said, is a smaller than Foreman valis. So it's not gonna be the mandibular branch. We talked about optic nerve going through the optic canals. And also um the other things that we discussed as well. Um So yeah, it's spot on, let's move on. So now we've got a patient who has conductive hearing loss. So, meaning it's not something to do with uh the sensory neurons pathway and the muscle attached to the stapes has been affected, which nerve innervates the muscle affected. So, um I think II might have actually forgot to mention this. There is two muscles that are in the ea that you need to know about, which is gonna be your estates and it's gonna be tensor tympani. I used to remember that tensor tympani has at is gonna supplied by trigeminal. And think about what is if we talk about vestibular co cochlear and facial nerve going through the er internal auditory meatus. So there is two nerves out there and vestibulo cochlear is only gonna supply your cochlear and er your balance. So what is gonna be the, the nerve that is left to supply your stakes? So, essentially a muscle attached to your um este and what it does, it, it tenses it, it doesn't let your ear get damaged by very high frequencies. What, what would be the nerve based on what we said? Now, any guesses. So think of it as phrenic, where does it supply the supplies it diaphragm. So probably not that Vegas vagus usually supplies a lot of things parasympathetic to your thorax, abdo abdominal viscera, et cetera. It supplies um your larynx, but actually it's, it's not gonna supply that high up. Think about trigeminal, we talked about it. That one is not the answer. So the one that is left is facial. So I used to remember facial nerve stapedius. Um and then we have trigeminal to tens tympani. So these are the two muscles that are like very small, they are in the middle ear. So which of the following nerves causes a lateral glands secretion. So we talked about this and think about the regions where all of these cranial nerves supply. So mandibular branch of trigeminal nerve, maxillary branch of branch of trigeminal nerve, facial and glossopharyngeal. Only two of actually not two, actually three of these ones have parasympathetic um nerves. So for secretion, when you're parasympathetic. Secondly, think about where do these supply or where do they innovate and then think about is that structure in that position. So any ideas, you know what this one could be p for facia? Any, any other, any other guesses? You're all shy? Yeah, absolutely fine. You're right freya. So it is facial. So think of it as glossopharyngeal, what it does, it is parasympathetic to a lot of places you're gonna learn about in more in detail the next session, your anatomy but is lower down your throat, er, going down to your er, essentially er carotid arteries, the bowel receptors there. Uh but it's quite low down. Er, the mandibular branch of your trigeminal does have parasympathetic, but it is again, low down. So if you see any secretion around here, you might think about it, er, the trigeminal, but here you would think about facial nerves, some, some parts of it is memorization. I'm just trying to help you guys to actually not say, oh, I just got me. Absolutely everything. So there is some reasoning to how to remember these and stuff. So how do you guys think is spinal fluid absorbed back to the venous circulation? I personally did not say mention this. Why? Because I wanted to not to spoil it for an SBA er but actually how do you guys think it's absorbed back to the venous circulation? Is it via Arachnoid granulation? Is it v sigmoid sinus? Is it via internal jugular vein or it doesn't actually go to the veins? Any ideas? Thanks Freya. So a any other person so Freya's on, on fire? But yeah, thanks Derek as well. So a I'll agree with both of you guys. So Arachnoid granulation spot on. So this could be essentially a very good ba but it could also be a short answer question. So I could ask you how would it be absorbed back to the venous circulation? Arachnoid granulation, one answer spot on. So we have emissary veins that what they essentially do is some of these will not go via Arachnoid granulations. They will go to what some of the veins in your er bones of their head. But that's a bit more niche the one you need to focus on is arachnoid granulations spot on. So now we have a patient who's had an oculomotor nerve palsy, which, which of the following, er, is least likely to be affected. So, three of them are more likely to be affected, which one is the least likely to be affected because of the oculomotor nerve palsy. So, nerve palsy means that, that nerve is damaged. So you might have Bell's palsy, which is essentially facial nerve damage. You will get drooping of the face, et cetera. But it is oculomotor nerve palsy. So, is it lateral rectus, medial rectus, inferior rectus or superior rectus? Thanks guys. So, a lateral rectus. Anyone else has any opinions of what it could be? Just guys give it a go. I'm not saying you guys are wrong anyone else? Well, because you're on fire. So it is lateral rectus. We talked about lateral rectus being abductors and they are s er er innervated via abducens nerve. And e essentially a superior oblique is gonna be well trochlear, but the rest are oculomotor spot on. So they could potentially ask you questions like this as well. Which one of the following is true? Um So usually questions are not like this, but you do get some of these as well. So it's a little bit harder. The semicircular canals help us to detect linear acceleration. Primarily the ossicles are found in the outer ear, the sts can uh sorry, connect to the round window of the cochlear. So we have the round and oval window, think of which one does the sts connect to? And the and saccule help us to detect linear acceleration. It's a little bit harder. Try to maybe sometimes go away and ruling out options. So which one do you guys think is the right answer? So Freyer, thank you. So d any other responses? So let's walk through all of the options. So option A is telling us, semicircle canal helps us to detect linear acceleration. We talked about the fact that semicircle canals are usually involved mainly primarily for um essentially balance, so not linear acceleration, it's not the prima pri like er primary job, the obstacles which are the little bones are found in the outer ear. No, they're actually in the middle ear. So the sts connect to the round window of the cochlear, they actually connect to the oval window of the cochlear. So that's the one that you just got to make sure you don't get mixed up. So round window is gonna be the one that is below um oval window. What it does is the fluid was pushed in, it just comes a little bit back out. So it kind of like balances it. But yeah, absolutely. So d is the right answer. Good job guys. Um So we've gone through a lot of SBA. So I tried to bring on a lot more as you guys have requested. I hope you have enjoyed the, the session today. If you have any questions, feel free to unmute yourself, stay behind. Ask me. Now, er we have tried to stick to the time as well. Um So thanks for all of your contributions as well. So you guys are on fire. Brilliant. Um And yeah, so if you have any questions, you can always email me as well. So we highlighted the most important aspects um, of uh the first two sessions. Pretty much. If you know everything that is in this powerpoint, you don't need to look at the like anatomy handbook anymore. But essentially anatomy handbook is always a very good resource if you are unsure about anything. But, yeah, brilliant guys. Er, if you wanted to leave as well, feel free to leave, er, if you've got the feedback form again, you guys can just fill it in, make sure you do that to make sure you get um, your certificates and also we, we will be provided with some um, evidence as well to be able to know how to improve. But yeah, thanks guys. You're welcome guys. The.