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Hello. Hi, everyone. Uh Thanks a lot for joining in on a Thursday afternoon. Um I'm just gonna give it a couple more minutes for a few more people to arrive and then we'll get started. It should be a nice and short session today just covering, you know, the relevant stuff, hopefully. Um So yeah, we'll just give it a couple more minutes. Hello. Hello, welcome. Just waiting a couple of minutes. Okay. So first of all, can you guys hear me? Perfect. Okay. So as you guys, I'm pretty sure some of you have been through this session before is basically we're going to go through a few MCQ questions taken from pass met covering major themes as well as some, some teaching in between questions as well. How it works is I'm gonna, we're gonna have a look at the question. I'm gonna bring up polls for answers for each question and then you guys can interact with the polls. Okay? I won't pick anyone out to answer the questions. Uh And you guys can ask me at any time throughout the session if you have any questions through the chair and I'll try my best to answer the questions. Okay. Right. So today's session on neurosurgery. Um you know, sometimes it can be a bit of a niche one. Um But there are some that can come out. It's a bit of a mix of, there's a bit of overlap with neurology in this session today. But, um I've tried to cover like more of the high yield topics for today just to, just to make sure that you guys actually get something out of this. All right. So headache, another very common presenting complaint. Um Everyone gets headaches. Um Of course, we use Socrates as well. Headache is a type of pain. So you, you still use Socrates for it. And then after Socrates, you do a systems review as well. Um I've got a list of the systems review on the right. Um Just sort of ruling out any causes of headaches or secondary causes of headaches. Specifically things like asking about trauma, fever, weight loss, meningism, uh G C A which is giant cell arthritis, um seizures and loss of consciousness, stroke symptoms like neurological deficits on one side and space occupying lesion's okay. So these are, these are the things you should think about when someone presents with the headache just to rule out some of the serious causes. Um You guys will get the slides at the very end once you feel in the feedback form. So you, you guys can have a read of this once, once we're done. So can anyone tell me how we classify headaches? Well, there's specifically two types that I'm thinking about, um, probably in the chat if you know, well, it's primary and secondary headaches. So those are the two types of headaches. I was, I was thinking about, um, what's the difference between a primary and a secondary headache? A primary headache just means that there's no specific underlying cause. So, so these are things like tension headaches and migraines, not saying there's no cause, but there is not associated with like a completely different condition. So that's what primary headaches are. Secondary headaches are headaches that are associated with a separate condition. So things like a space occupying lesion um or bleed are examples of secondary headaches. Okay. So those are the those are how people split headaches. So there's primary and secondary headaches. Okay. But can anyone give me other examples of primary headaches? I've already mentioned migraine and tension headaches. So you guys think of any other other causes of primary headaches? Pop it in the chat if you know any, if not, it's fine. Yeah, cluster headaches, cluster headaches. A really bad one especially for is, is more common in men. Men get it quite a lot, smokers get it a lot as well. Cluster headaches aside from cluster headaches, anything else? Let's see what, what I've put down here. So there's migraine tension headaches, cluster headaches and trigeminal neuralgia. It's considered a primary headache as well. Okay. Um now for secondary causes, I've mentioned meningitis and space occupying Malaysians um and a bleed. Um Yeah, I think that's mainly it temporal arthritis, closure, glaucoma as well is considered a secondary cause an acute sinusitis as well. Video pathic intracranial hypertension also quite a common one in obese females, middle aged females that can be quite common. Okay. It's another secondary cause of secondary headaches. Uh it's not the cause of secondary headaches. Sorry. So these are the difference between primary and secondary causes. So that's all we are. We are at for headaches, I think. So we've got a quick anatomy recap of the brain. Um So the brain is separated into four lobes, frontal, temporal, parietal and occipital okay. And the two hemispheres of the brain are separated by the longitudinal fissure. Um and then horizontally, there's the central sulcus which separates the frontal lobe and parietal lobe. And then at the very back, there's also the parietal occipital sulcus which separates the parietal lobe and the occipital lobes. So it's just, it's just a quick recap on the anatomy, quick recap on the meningioma layers. So the three meningeal layers under dura meter, air economic meter and P A meter uh on the right. Um You can see the bone at the very top and then there's the dura meter just beneath the bone and then beneath the dura meter. That's the subdural space. And then the subdural space is basically between the parameter and I reckon ah meter and then between the arachnoid mater and the PM eater, that's the subarachnoid space. So that's just a quick, quick run through of the of the manja layers and then the ventricles in the brain. So there's four ventricles in the brain. The two lateral ventricles that drain into the third ventricle and then the third ventricle drains via the cerebral aqueduct into the fourth ventricle. Okay. So the ventricles in the brain, if you remember, they produce and store cerebrospinal fluid. Now, the cells that produce the cerebrospinal fluid are called the correct plexuses. And they're essentially just epithelial cells around the ventricles. You, they're, they're in the lateral ventricles and that the ventricles and the far ventricles, they're, they're sort of all over the place and they basically produce the cerebrospinal fluid. And then the cerebral spinal fluid fluid basically goes all the way around the meninges, all the way around the spinal cord and then they eventually drain into these structures called a retinoid granulations in the subarachnoid space that basically just soak up all the CSF like a sponge and then deposit them into the venous system in the brain and the main venous system in the brain, I think is the dural venous sinus. Okay. So quick overview of the ventricles in the brain and what they do right now on to question one. Uh Okay. I'm gonna give you guys 60 seconds for this one. Well, if you do have any questions, just pop it in the chat. All right. 10 more seconds. Okay. Let's call it there. So the answer is an extradural hematoma. Well done. Um So if we have a look at the question, it's a 25 year old branded emergency department after being struck on the side of the head with a bottle in the nightclub wild night. So he was not unconscious and then regained consciousness and then the patient lost consciousness again. So this is a very classic presentation of an extradural hematoma. Um So what is the phenomena that's the patient is experiencing? Called this, this what was it called? When the patient loses consciousness, regains consciousness and then loses consciousness again. In this case, I'm sorry if you guys are typing in the chair and it's just a bit late for me. Yeah. Well, that remains a lucid interval. So this um this patient is undergoing something called a lucid interval. And lucid interval refers to the regaining of consciousness in between, that's what it's specifically referring to. Okay, balut in control. So loses loses consciousness at the point of trauma, regained conscious and then loses again. Okay. Um So does anyone know why this happens? Why does the lucid interval actually happen in this case? Okay. Well, um it's because the initial impact causes a loss of consciousness and then they regain consciousness from the initial impact and then there's a hematoma forming um within, within the, within the cranial cavity and as that expands, that causes um, um it could cause possible herniation and that could cause um pressure on the brain and that could cause him to lose consciousness again. So that's actually what's happening. That's why the lucid interval happens in the first place. Okay. Um, now one of the options was a diffuse axonal injury. Okay. And what that is is, is basically an injury that occurs commonly in deceleration accidents like a car accident. So when the car crashes into a wall or into another car, um the the the sudden deceleration causes a lot of shearing forces and mechanical tearing in the axons of the brain. So the long the long neurons in the brain get torn okay. It's a very severe injury can cause coma. It can cause severe neurological deficits and that's simply not the mechanism. In this case, we'll talk a bit about acute subdural hematoma in a bit. Um confusion just it just doesn't, it just doesn't apply in this situation. Um, concussion maybe, but it doesn't apply to his symptoms which is why those are not the answers. Okay. So the key point, Lucy interval is associated with extradural hematoma question too. I'll give you guys about 60 seconds for this one as well. Yeah, and that's alright. 10 more seconds type of guess. Okay. So we've got quite a big split on this one and the answer is a subdural hematoma. Now, I can understand why a few of you might have chosen Korsakov and Vern occurs because um they did say she has a history of alcohol abuse. Okay. Um But if you look at the whole picture of this lady, it's an old lady presenting with confusion, headaches for the past week. So it's not acute history of alcohol access and she's on warfarin as well. Is it Warfarin? Yeah, she's on Warfarin as well and she's also had, she was also assessed over the past year for frequent falls. So all these risk factors and the onset of her symptoms which include confusion um point more towards a subdural hematoma. Okay. Now, why is it not Korsakov's and vinegars? Because okay. So in Carsick Auvs is that it's the traditional triad of symptoms which is nystagmus, a taxi to um what was it? A stag mus a tax eah and confusion. I think. So she doesn't have nystagmus. She doesn't have a taxi a she does have false but there's no, there's nothing in the problem that says she's got sort of loss of balance from it could be from anything else. Ok. Vernick Ear's sorry, sorry. What I mentioned just now was actually ver knickers. It was not Korsakov's verticals was the trial of nystagmus. Um a taxi and confusion. Korsakov's is what happens if you don't treat Benicar's and you develop Korsakoff syndrome as well. So if you have verticals first and you don't treat it, you get ver knickers and Korsakov's as well and Korsakov's is basically and tear a great and retrograde amnesia. So they forget going forward and going backward and they confabulation which means they tell lies or they tell stories that aren't true. Okay. So those don't apply. In this case, extra extradural hematoma, as we mentioned before, there's no lucid interval. So that's not the case here. We'll talk about subarachnoid hemorrhage in a bit. Okay. Yeah. And as mentioned before, it's not acute. It often develops over days, weeks or even months. Okay. So that's, that's how long subdural hematomas can develop over time. All right. Uh Yeah. Yeah, we've talked about this. Yeah. Her age, her alcohol access and her warfarin are risk factors for subdural hematoma. I'll talk a bit more about what subdural and extradural hematomas are in a bit. Okay. Um Yeah, spells of confusion. Uh I've talked about Vernick ear's and Korsakov's. You guys can have a read once and careful opathy. Yeah, that's what I meant. So for Ver knickers, it's nystagmus, a taxi and and careful opathy. Okay. And Korsakoff this amnesia and confabulation. All right. Question three again, 60 seconds. If you guys have any questions, just pop it in the chat, hopefully I'll explain all this once I actually reached the explanation slides, but any questions just shout out about 40 seconds for this one. Okay. So half of you a lot of you got this right? So this is a subdural hematoma. Okay, quick question. Which side is the hematoma? Is it the right or the left? Yeah, it's the right side. So remember when you're looking at a CT scan, your, it's like you're looking at it from the patient's feet. So whatever you see on the left is actually on the patient's right. So, yeah, well done. So in a subdural hematoma, always remember in the CT scan if you see a hyper or hypo dense area which, which, which signifies a bleed and it's concave. So it's like a banana shape more often than not. It's a subdural hematoma. Okay. So, yep. Okay. Now, is this an acute or chronic bleed? Uh Good guest George, it's actually a cute. So it's an acute bleed because it's hyper dense. So anything. So if you see a bleed that appears on a CT scan and it's brand, it's hyperdense is bright. That means it's an acute bleed. As, as more time progresses after a bleed, the bleed gets more and more dark. So it gets more hypodense. And the reason that is, is because the contents of the blood gets gets dissolved or digested in a way. So that's why it gets more and more dark or more hypodense. So you see the, this one is pretty bright, it's still pretty hyper dense. So that means it's acute. Okay. Yep. Yep. So a subdural bleed can be either acute or chronic, you can see both. Um but we'll discuss this in a couple of slides time now a question for another 60 seconds. Okay. 10 seconds. Okay. I'm gonna stop it there. Okay. So now let's go through this. The answer was rupture of bridging veins. Okay. So the reason that is, uh, let's go through the history itself. So we've got a 72 year old male. So he's old. He's become more confused recently. So it sounds like he is not really an acute thing. Uh, he's had frequent falls in the past a long standing history of alcohol access. Okay. So he's got three of the main risk factors for what we discussed was a subdural hematoma. So it sounds like he's got a subdural hematoma. Um and the mechanism for a subdural hematoma um is rupture of the bridging veins, okay. And we'll again, we'll talk more about this once, once we reach, but just remember subdural hematoma rupture of bridging veins. Now, what, what are these bridging veins? I'll tell you, I'll tell you in a few slides time. Let's let's do the next question first. Okay. Question five. I'll give you guys another 60 seconds for this one. Okay. 10 more seconds. Okay. So before I show you the answer, let's talk about what's going on in this, in this unfortunate patient here. So, on the CT, you can see this hyper dense uh collection of blood on the patient's left side, okay. Um And it's convex shape. So, as we mentioned before, the subdural hematoma had a concave banana shape. So this is a convex shape. Okay. So what this city is telling us is that the patient has an extradural hematoma, okay? Because it's limited by the suture lines and it's pressing on the dura impressing the brain tissue inwards. So that's, that's why you get the convex shape. And that's why this is an extradural hematoma. And one of the most common cause is, is something called a fracture of the terrian. Okay. And I'll show you what the terrian looks like. All right. So the answer is fracture of dietary in, I don't know why that's there, that shouldn't be there. But yeah, so okay, never mind. So an extradural hemorrhage is basically blood in between the skull and the dura mater, as we mentioned before, the meningea layers, the skull and then the dura meter and then the arachnoid mater and so on. So the in an extradural hemorrhage is between the outermost meningea layer and the skull. So the reason I, as I mentioned before, the reason why it was a convex shape is because the suture lines are connected between the skull and the dura. So the blood that accumulates within the extradural space can't cross the suture lines, which is why, which is why it forms the convex shape. Okay. No, what type of injury commonly causes an extra dual hemorrhage. We went through a few questions regarding this but just shouted out in the chat. Yeah. So it's a hit to the head, specifically, it's a hit to the side of the head, okay into an area called the Tarean. But why is the side of the head vulnerable if anyone knows? Yeah, it's the weak bone. And the reason it's the weak bone is because it's the junction between four of the scalp bones. Okay. So it's the parietal, the sphenoid. Um I actually forgot what the other two were, but it should be here, but it's basically the junction of four of the bones. So four of the suture lines actually connect into this one area called the Tarean. Okay. So it's a head shape, junction of the frontal, the sphenoid, the parietal and the squamous bones. Yeah. So it's the, it's the junction of four suture lines which is why it's, it's one of the weaker sides. It's one of the weaker parts of the skull. Okay. Now, injury to this area causes damage to which vessel. Yeah, the middle meningeal artery. So, right where the Tarean is the middle, the middle meningeal artery runs just along the tarry in between the dura and the skull. Okay. So as soon as there's trauma there, the skull chatters and it shares away at the middle meningeal artery, it bleeds and then it forms that extradural hematoma. So that's exactly what happens in an extra dural, extradural hemorrhage. Okay. Uh Yep. So that's where it is okay. The Tarean is right right here in the temple in the temple area. Right here in the middle meningeal artery goes right through it. Okay. So hopefully that makes sense. Now, we'll talk about the subdural hemorrhage etiology, okay. Um So the subdural hemorrhage, extradural hemorrhage is above the dura, subdural hemorrhage is below the dura. So it's between the dura and the arachnoid meter. Okay. Um So what causes the bleeding? Usually? Now, if you remember one of the answers was the bridging veins in the subject space. So, bridging veins are basically just veins that travel in between the subdural space. Okay. So that's, that's those things that rupture in the subdural hemorrhage and an extradural hemorrhage. It was the middle of meningeal artery in the subdural hemorrhage is the bridging veins in the subdural space. Uh And there are two types of subdural hemorrhage is as we've mentioned before. It's acute and chronic. So for acute um it's usually trauma, it's high impact trauma, high impact trauma can cause acute subdural hemorrhage is okay. Um But what are the risk factors for a chronic subdural? I know we've talked about this before but can you just can you some of you just shout out a few in the chat? Yeah. Yeah. More free. Yeah. Recurrent falls. So warfarin recurrent falls and there was also old age and alcohol. Okay. Now you might be wondering why does why does old age and alcohol increase the risk of a subdural hematoma? Can any of you think why or have an idea as to why this might be a risk factor aside from the recurrent falls, obviously, because you can have recurrent falls in elderly people. But basically, yes. Yes, George. So as you grow older, the brain atrophies and it grows smaller. So as the brain grows smaller, the bridging veins in the subdural space actually stretch and they become taught. So even a bit more. Yeah. And the vessels become weaker as well. So it takes less force to damage these vessels. Okay. And when the vessels are damaged, they aren't catastrophic. They tend to be minor cuts or minor tears and blood just slowly leaks into the subdural space, which is why subdural hematomas don't have an acute onset. They don't for chronic subdural hematomas, you don't have an acute onset. It's not like sudden like that. It can usually develop over days, weeks or even months, which is why there's intervals of like confusion, which is what you can see in a subdural hematoma, okay. Um Drinking also causes the brain to shrink as well uh causing the same risk factors as old age. So that's why uh Warfarin because obviously it it makes blood harder to clot and if there are bleeds, then it'll just continue bleeding. So that's why. Okay. I found this quite nice picture on the internet uh saying like stating the difference between an epidural and a subdural hematoma, okay. Um So just remember an epidural hematoma is a convex shape and a subdural hematoma is a banana concave shape. Okay. And the subdural hematoma can cross the suture lines but an epidural sorry extradural hematoma can't cross the suture lines. Just remember that for, for these two. And I think, I think you should be fine. Okay. Um, so investigations for both is just a CT scan. Essentially. You, you do that for any, any anyone you suspect might have, uh, might have a brain bleed essentially. Can subdural hematoma be a differential for vascular dementia. Yeah, definitely. Um but vascular dementia is usually like vascular dementia is usually caused by things like a stroke. Okay. So interest cerebral ischemia sort of of the brain causes that dementia. It can be. But if it is a subdural hematoma, you should be able to see it clearly on the CT. It can be a differential for for vascular dementia. Yeah, vascular dementia is usually caused by like stroke. It usually occurs after stroke. Essentially, that's what that's what happens. And a subdural hematoma is not a stroke, okay. It's just a bleed in one of the meningeal layers of the brain. Okay. So, treatment is found incidentally and there's no neuro deficit you can admit for observation and conservative management, okay. And usually the bleeding will get absorbed over time. Um But if it's catastrophic, there's a lot of bleeding to the point where it's forming like a space occupying lesion, then something called a decompressive craniotomy is performed. And what that is is you basically just take out a piece of the skull, you suction up all the blood that's in there. And then at the end you put the skull back in and then hopefully that should um decrease the swelling of the brain itself because that's the thing you're worried about. If it's, if the bleeding is catastrophic, it swells up and then the blame gets damaged more and more and then it can lead to ischemia and so on. Okay. So that's why they do a decompressive craniotomy. Right? Hopefully that all makes sense. Any questions just let me know. But otherwise onto question six, let's see. 50 seconds from here, maybe, maybe. Um 45. All right, five seconds. How many questions today? Um Not that many, not that many. I think I've only got like 14 questions today. I wanted to keep it nice and relevant and short for today and hopefully, I kind of want to finish on time. Um So yeah, we'll, we'll try to go slightly quicker. Okay. Um Right. So, well, then the answer to this one is a trans tentorial herniation. Okay. So basically what happens is when someone gets major trauma to the head, there's catastrophic bleeding, the blood that rushes in can push structures of the brain uh uh sort of downward into the only into the only place it can go because the skull is basically a box. If they're swelling, the brain can't go anywhere aside from down. Right. Through the foramen magnum. Okay. Um So when this happens, um if you see in the middle there, there's where trans tentorial herniation happens. It goes through something called the tentorium cerebelli. Okay, which is the, which is the connective tissue in between. And what happens when parts of the brain gets pushed down, they push against the c and the cranial nerve three on the midbrain. Okay. So right in the mid brain, that's where the herniation pushes against and that's why you get the blown out pupil. Okay? Because if you remember parasympathetic fibers run through the C N three and when that gets disrupted the sympathetic takeover and that's why you get blown up people. Okay. So if you see someone with a lower G C S history of head trauma blown up people almost always is a 10 to 10 trans tentorial herniation. Okay. So hopefully that made sense now, questions seven. I'll give you guys about 45 seconds from here. Excuse me? I think so. I think so. Charmaine, I don't think you need to be aware of the other nations. Those get a bit specialized. Just know that lower G C S. Um Oh, thank you. Thanks, Savina. Just know that lower G C S and blown up people, some form of herniation must be happening. That's an emergency. He needs a craniotomy right there and then immediate referral to surgery essentially. Okay. That's all you need to know for now. All right. 10 more seconds. Okay. Well, then most of you got the answer. So it is a noncontrast CT head. So, first of all, what is this patient presenting with? Well, but yeah. So what is this, what is this patient presenting with? But, I mean, it's completely okay. So he's got history. Yeah. Well done. So he's got a subarachnoid hemorrhage. Okay. He's got to our history of a severe headache. She describes it as the worst headache she's ever had in her life. It's sudden onset and she's vomited twice. She's also got um she's also got some mild neck stiffness and photophobia, which is meningism. Okay. Um So the patient has a subarachnoid hemorrhage. Um and the first line investigation is a noncontrast CT head. Okay. As you can tell from the name a sub arachnoid hemorrhage is basically a bleed underneath the arachnoid mater in between the Arachnoid and the pr okay. Um Okay. So why do we not use contrast? Why, why, why don't we use contrast in this case? If anyone knows, obviously, if the patient has rino rino dysfunction, you wouldn't use contrast anyway. But let's say this patient has, has normal renal function, why would you still not use contrast? Yep. So the it's an acute bleed. So blood will be hyperdense and the contrast will be hyperdense as well. If you just inject contrast, it'll just mask out the bleeding. So that's why you don't use contrast in this case. Okay. Um So any acute bleed, it could be a stroke, it could be a subdural, it could be a subarachnoid. Um Don't use contrast anything with an acute bleed essentially or that's what applies to most cases. It really depends on the practitioner or the radiologist. But I would say for most acute beliefs that don't really use contrast for it, okay, you're use contrast for things that are enhanced by contrast like a tumor, for example, um you don't do a lumbar puncture in this case and I'll explain why in a bit. Okay. So a CT angiogram is used to look for an aneurysm that cause the subarachnoid hemorrhage after it's been confirmed on a CT. So once you do a CT and you can see that there's a subarachnoid hemorrhage, then you do a CT angiogram to look for the source of the bleeding. So use the CT angiogram for that. Okay. So hopefully that makes sense, key point, subarachnoid hemorrhage, non contrast. CT, that's what you do first line investigation all the time, a bit about subarachnoid hemorrhages. So we've talked about extradural and subdural. Now we're going a layer below. So it's blood in the subarachnoid space in between the arachnoid and pia and it's around the sol chi and the giro of the brain, you know, all the wrinkles. So that's where the spaces. All right. So the PCR is the is the very is the is the is the layer closest to the brain and it actually conforms with all the gyro and the salt kind of the brain. So the the arachnoid is just above that and the subarachnoid space is this entire space conforming through the sulky and the gi right of the brain. And if you see on the image, you can see blood or hyperdense blood in something called the Sylvian fissures and the basil systems. Okay. So what, what's the Sylvian fissure? What, what's, what's the basil system is basically expansions of the subarachnoid space, as I mentioned before, to transmit structures through the brain. Okay. That's, that's all you need to know for now. Okay. Um They often call this like a butterfly shape. I don't actually, I don't actually see it but if you see if you see sort of these hyperdense markings on, on the picture on the, on the left, okay. Um And they're hyperdense in these areas, it tends to be a subarachnoid hemorrhage. Okay. Hopefully, that makes sense. Now, the symptoms of a subarachnoid hemorrhage, as I've mentioned before, as we've seen before. Um a severe headache is like people, you guys must have heard this. It's like a thunderclap headache is like getting hit in the back of the head with a bat is what it feels like. It's very sudden, it's very intense, very painful. Usually, maximum pain comes on over a minute to five minutes. Ok. That's how quickly, that's how quickly it comes. It's very intense tends to be occipital as well. So at the back of the head, but not necessarily. Um and there may be a history of like a less severe headache in the weeks prior to the presentation, but um just the thunderclap headache is the, is the characteristic one. Okay. You can get knowledge and vomiting as well, uh, and signs of meninges. Um, because there's blood around the meninges, that's why you get meninges. Um I'm not exactly sure why you don't necessarily get meningism in extradural or subdural hematomas. But you get meningism in, in subarachnoid hemorrhage, they're all in the manager layers, but I don't know why subarachnoid hemorrhage specifically irritates the many MGS but subarachnoid hemorrhage. Meningism common. Okay. Um If it's really bad, you can get a coma and seizures, right? Hopefully, that makes sense. Question eight. Okay. Let's see. 45 40 seconds from here. Uh Yes, we'll get to that Charmaine. We'll get to that. This question has, has a relation to that. So I don't want to reveal any answers yet. All right. Five more seconds. Mhm. Okay. So 46 year old men emergency department, sudden onset severe headache, some neck stiffness is parexel. Um Now he's asking what I would suggest a subarachnoid hemorrhage rather than back to the meningitis. So they're asking which of these are associated with a brain bleed more than an infection. Okay. And the answer is family history of polycystic kidney disease. Um Okay. So let's let's talk about the causes of supper right now in haemorrhage first. Okay. So the most common cause is trauma and there's, there's two types. So there's a traumatic subarachnoid hemorrhage and a spontaneous subarachnoid hemorrhage. A traumatic submarine subarachnoid hemorrhage uh is self explanatory hit to the head causes the subarachnoid to bleed. But a spontaneous subarachnoid hemorrhage isn't precipitated by trauma. So, what are the causes of a spontaneous hemorrhage? So, Charmaine, you mentioned a berry aneurysm and that is actually the most common cause of a sub, right? Not hemorrhage. Can you guys think of any other causes? It's fine if you don't because I didn't know this as well. It is pretty niche to be fair, but I think it would be good to know. Yeah, I think vasculitis can cause subarachnoid hemorrhage is basically just inflammation of the, of the vessels in it and it can be vessels in anywhere. So, yeah, essentially vasculitis can cause subarachnoid hemorrhage, but it's not typically associated. So it's arterial venous malformations. Um and pituitary apoplexy, which is basically just severe bleeding of the pituitary. But I'm pretty sure vasculitis does increase the risk of subarachnoid hemorrhage. I think I'll have to look that up. I'll have to look that up, but basically Berry aneurysms. Um Sorry, it's not, it's not 5%. It's meant to be 85%. I need to fix that. Okay. It's not 5%. It's, it's meant it's way more than that. It's 85%. Um, I think, but yeah, it's very aneurysms is the most common cause and things that increase the risk of berry aneurysms include hypertension, adult polycystic kidney disease and connective tissue disease called uh, inhalers done Loss syndrome. Okay. They all increase the risk of berry aneurysms. So, now you might be asking me what, what, what are very aneurysms? Okay. What, what, what's, what's a Berry aneurysm? Um, basically what it is. Um, okay, I should have a picture of it here. Okay. Yeah, there it is. So berry aneurysms are basically just round blood filled sacs that protrude from main arteries. Okay. And it usually forms on the arteries at the circle of Willis is which is basically a collection of arteries at the base of the brain. Okay. So if you can see on the picture on the right, um 40% of the berry aneurysms form near the anterior side of this circle of Willis. Okay. So the circle of Willis is just this collection of arteries. You'll learn it eventually. If you're, if you're quite, if you're, if you're quite early in your years, you'll, you'll learn it eventually, but just, just know that it's an important structure in the brain for now and berry aneurysms form there. Okay. So that's what usually causes subarachnoid hemorrhages, spontaneous subarachnoid hemorrhages, berry aneurysms. Um Okay. So hopefully that makes sense. Let's move on to question nine just to, just to, just to let you guys know it is the rupture of the berry aneurysm. Not just the berry aneurysm itself that causes the bleed. Okay. Okay. 45 seconds from here. Okay. Five seconds. Okay. I managed to catch you guys out with this one. So let's go through the question. Severe headache, um, sudden onset headache, worst, worst headache she's ever had meninges. Um Sounds like a subarachnoid hemorrhage to me, but you do a CT. Um and there's nothing, there's nothing on the CT. Um So what do you do? So a few of you set CT angiogram and you only do a CT angiogram when you've confirmed a subarachnoid hemorrhage on a CT scan. And in this case, you haven't confirmed it, there's, there's nothing showing a subarachnoid hemorrhage on the CT scan. So you can't, you can't do a CT angiogram. In this case, magnetic resonance angiography wouldn't is basically like an angiogram as well. So it wouldn't, it wouldn't add more to this case in this case. Um A a lot of you chose lumbar puncture and that would be correct a few years ago. So the guidelines for this recently changed and the answer to this actually to consider an alternative diagnosis. So if it's seepy, so the C P here is performed one hour after hour assessment, okay. Um If the CT is done within six hours of a suspected subarachnoid hemorrhage and there is no evidence of a subarachnoid hemorrhage guidelines actually recommend considering an alternative diagnosis, they no longer recommend doing a lumber puncture a few years ago. It was, if you can't find anything on the CT, you do a lumbar puncture. But if you do it nowadays, if you do a CT, within six hours of onset of symptoms, you don't do a lumbar puncture anymore. You, it's considered, you've ruled it out essentially. Um I don't exactly know when they've changed the guidelines for this, but I, I have noticed that they've changed it. Um So when you do a lumbar puncture, if you do a CT after six hours since symptom onset, so let's say the patient presented with this severe headache seven hours ago, you do a CT and you find nothing on the CT, then you can do a lumbar puncture. Um And the reason for this, it could be because the blood has settled down and that's why you can't find anything on the CT because remember blood gets more hyper dense as it gets less acute. Okay. So that's why you do a lumbar puncture. When will you do a lumbar puncture if it is indicated? So let's say a patient comes in eight hours post symptoms and you want to do a lumbar puncture. When do you actually do the lumbar puncture? You might be thinking of meningitis in this case. Um But that, that's not, that's not the case. Yes, George, it's 12 hours. So you do, you do a lumber puncture 12 hours after onset of symptoms Okay. So that's when you do, that's when you do a lumbar puncture. Okay. Um Yeah. So as I mentioned before, that's not the case anymore. Um So after you confirm a subarachnoid hemorrhage, that's when you do a CT angiogram, a digital subtraction angiography is basically just another CT angiogram if you can't find an aneurysm essentially. Okay. So we'll talk a bit about investigation subarachnoid hemorrhage. So you do a CT head noncontrast immediately if there is an evidence of a subarachnoid hemorrhage. So you see hyperdense in the basal cisterns and Sylvian Fishers send them straight for a CT angiogram to look for the source of the bleed or the aneurysm, the berry aneurysm we talked about okay. If the patient comes in within six hours of the symptom onset and you see nothing on the CT scan, consider an alternative diagnosis. It could be something else. If the CT, if the patient comes in more than six hours since she's got, she's got the symptoms. You do a CT scan, there's nothing, then you perform a lumber puncture 12 hours after symptom onset. So this, this is sort of like the guideline for now. Okay. Um Now if a lumbar puncture in was done, what would we be looking for? In the meantime, I'm just gonna drop the feedback form if any of you have to leave early. Okay, I appreciate you guys staying back. It shouldn't last much longer. But if you do have to leave, please fill in the feedback form first. I'll send the feedback form again at the very end. Yep, you're looking for. Yeah. At the specific word I'm looking for is Entocort me a well done Jordan Xanthochromia. So, what is Santos? What is Xanthochromia? If anyone can tell me what, what is it actually, you know, the medical seen, they love to just throw words around and I went through a lot of medical school just memorizing words without actually understanding what they mean. Surprisingly enough, it got me pretty far. Yeah, blood stained CSF. Um uh well, I wouldn't say is bloodstained CSF, but it's basically when blood gets broken down into a Billy Ruben and then the Billy Ruben causes a yellow discoloration of the CSF. So that's Xanthochromia. Okay. Um It's yellow discoloration of the CSF due to breakdown of hemoglobin to bilirubin. And that's also the reason why we have to wait 12 hours, um post 12 hours post symptoms to actually do it because if you do a lumbar puncture, there's bound to be some bleeding from the, from the traumatic puncture itself. So you need to differentiate the blood from there and the blood that's already been broken down. So that's why you do it 12 hours after, after onset of symptoms. Okay. Um Yeah, so that's what it looks like. So then Xanthochromia is a slight yellowish hue and CSF is usually just perfectly clear. Okay. Hopefully that makes sense. Question. 10 we've only got about four or five left after this uh 45 seconds for this one. Oh, wait the polls. Yep. There we go. Alright. 10 seconds. Okay. Okay. So it was between Nifedipine and niMODipine and honestly, I I've had this mixed up so many times myself. Um and I just never learned. Um So the answer is actually niMODipine. Yeah. So always remember Nifedipine, amLODIPine, dilTIAZem, Felodipine, they're all used for hypertension. So the one that's not, you've never heard of used for hypertension. That's the one used for for for this case. Okay. So they asked. So the CT scan shows hyperdense across the basil systems and Sakai. So he's got a subarachnoid hemorrhage. So which of the following is indicated in managing the complication of this condition. So the complication they're talking about in this case is vessel spasms, okay. Um Okay. So the reason you want to stop having vasospasm in some of the subarachnoid hemorrhage is because vasospasm can cause further ischemia of the brain tissue if not managed. So, niMODipine is used okay, not Nifedipine, niMODipine and Nifedipine both work the same way. They're both calcium channel blockers of the nondihydropyridine type. But niMODipine specifically targets brain vasculature, which is why it's used Nifedipine. And all the other ones are they work on the blood vessels and the rest of the body. But niMODipine specifically targets brain tissue, brain vasculature, which is why they use it. Okay. Now, question 11 four more guys. Four more questions. Okay. 45 seconds from here. Maybe even less. Okay. Five more seconds. Okay. All right. So what's going on in this patient? Um, lumber puncture, taken 12 hours later. Positive for Xanthochromia subarachnoid hemorrhages. Diagnosed ct cerebral angiography indicates posterior communicating artery aneurysm. Okay. So, an aneurysm is causing this subarachnoid hemorrhage. So, what is the optimal treatment for patient in this case? Okay. So an insertion of an extra ventricular drain is for hydro catalyst. So you wouldn't use it in this case. Extracranial intracranial bypass. I'm not even sure what that is, but I need to search that up. Uh niMODipine is to niMODipine is to control vessels, spasm. So it's not particularly optimal. So it's between coiling and surgical clipping, which are both used to treat aneurysms. But nowadays, people more like to use the coiling. Okay. Coiling by interventional neuroradiologist is less invasive. So what is coiling is basically they're inserting a wire through an artery in your groin and then they track it all the way up to your brain and then they find the aneurysm. Once they reach the aneurysm, they deposit these platinum coils in the aneurysm. Okay. And then once the coils fill out the aneurysm blood can enter the aneurysm as well. So it reduces the risk of further bleeding from that aneurysm. Okay. Um nowadays, most, most, most of the aneurysms or berry aneurysms or subarachnoid hemorrhage treatment is done through coiling by interventional neuroradiologist if for some reason you can't do coiling, then that's when they would do, um, sort of a neurosurgical procedure. They would manually just open up and then clip it manually. Ok. Which is way more invasive. So, which is why coiling is, is the way to go nowadays? Okay. So, coil so management for subarachnoid hemorrhage nowadays, coiling by interventional radiologist. Um, yeah, here is just a summary of the treatment for subarachnoid hemorrhage. You can, you can check that out later. Okay. All right. Three more, three more questions. Uh let's say 40 seconds from here, our arterial venous malformations managed. So I think you might have to do something quite invasive for that, especially if it's in the brain. I'll check for you. Mhm. I'll get back to you on that. Aisha after this question. Uh Okay. So really quickly Aisha. So there's a few ways to treat and A VM. So you can go through surgery. Um You can even try the endoscopic method. Um like the coiling, but AVMs are quite difficult to manage. So sometimes they may not even do anything for it simply because it's high risk. Okay. So they, they'll, they'll probably just manage sort of like the comorbidities like hypertension, um controlling, controlling sort of like alcohol intake and, and stuff like that is what they can do if the A VM is high risk essentially. Okay. All right. Hopefully that's, that's okay. Uh Now let's get through question 12. So patient ct attenuation of basil systems and sylvian fissure is yet another subarachnoid hemorrhage. Um And you can see that he's hyponatremia with a low serum osmolality. Um So low serum osmolality means that there's increased water intake. Okay. And all the things here. Uh I think SIADH is one of the only ones that can cause uh low serum osmolality. In this case, I think, I think let me just, I'll double check but one of the most common complications of a subarachnoid hemorrhage is a, is a SIADH. Okay. They come part in parcel. Um So okay. So other complications of subarachnoid hemorrhage include re bleeding, hydrocephalus, vasospasm, hyponatremia, seizures, okay. So just remember these are the complications of subarachnoid hemorrhage. Um SIADH very common. Uh Well, more common with people with subarachnoid hemorrhage and you should always keep a lookout for that. Okay, especially in your blood tests. Um I've got a summary of the bleeds. We've we've talked about today. Hopefully this will be helpful for you guys. You guys will get the, we'll get the slides once once we're done. Um We've just got two more questions today and then we're done two more. Okay. You guys have 60 seconds for this one. Um Yeah. So on the previous question, SIADH was one of the only ones that could have caused a low serum osmolality because SIADH causes a high urine osmolality because ADEH draws water up from the kidneys, okay. And it's producing too much ADH essentially. And that's because of the irritation of the pituitary from, from the blood from a subarachnoid hemorrhage just to clear things up. Okay. So, question 13. Well well done. Almost all of you got it. It's a basilar skull fracture. Okay. Um I wasn't meant to show you this image is okay. But basically in this case, is the peri orbital and post auricular bruising. What do you know what they're commonly called the peri orbital and postauricular bruising. There's like specific names for them if you guys can tell me. Yeah, battle sign. So battle sign is the postauricular bruising and then recognize for the peri orbital bruising. So those are signs of basilar skull fractures. What are the other signs of a basilar skull fracture, basil skull fracture? Yep, hemotympanum. And one more. I'm not actually sure what the halo sign is, but yeah, I was thinking of CSF leak. Yeah. So you can get CSF leak from the nose or from the ears. So that's a sign of basil skull fractures. What is absolutely indicate? What is absolutely contra indicated in a patient with the basal skull fracture. What must you never do in a patient with the basal skull fracture? It's got to do with feeding. Yeah. Never, never, never put an N G tube in a patient with a basal skull fracture. It's a, it's a never event. So I never do it very good. All right. So this is what the battle sign looks like it's right behind the ears and then this is the hemotympanum you'll see blood uh in the middle ear bulging out. Okay? We talked about this, we talked about this, we talked about this, I'll have to look at what the halo sign is gonna because I'm actually not sure what that is Oscar. Um But yeah, it could be something to do with it. I just, I just don't have the info. I just don't know what it is. Okay. Um Right. Last question. Just one on brain death. Last poll. Let's give you guys 30 seconds from here. All right. Well, I'll shorten it a lot of you have answered already. So, um so there's quite a big split in this. Um The actual answer is no response to sound because everything else is tested in brain death. Okay, corneal reflex, absent, Oculovestibular reflexes. If you guys remember what ocular vestibular reef plexuses, I'm pretty sure you guys have seen that diagram where it's like if you squirt cold water into one ear, the I diverts one way or if you squirt like like hot water and then the I diverts the other way. So that's, that's what ocular vestibular reflexes is. Okay. You do test super orbital pressure um in brain death and then the cough reflex as well. Okay. So this is like part of confirmation of death essentially or brain death. So, fixed pupils that do not respond to sharp changes in intensity of light. So that's the swinging light test corneal reflexes when I think you use cotton to see if the eyes blink, if you actually touch the cornea. Um I explained what an ocular vestibular reflex is super orbital pressure, no response to that cough reflex. So there is no gagging response if someone's brain dead and then no respiratory effort after they've been put off the ventilator typically for five minutes. Okay. So that was the last question. I'm sorry, I couldn't have, I I couldn't add more, but I didn't want to overrun too much as well without adding stuff that wasn't really necessary. So hopefully that was helpful. I try to focus on the topics that I think could potentially come out in exams. They wouldn't ask something to niche in this case. Um But thank you so much for coming. I'm just going to drop the feedback form again. Please do fill it out, please. It was, it's really helpful for me and Josh who's sadly not here today. Um Yes, Sharman, you can definitely get the colorectal slides. Of course. Um Can you just, I think I've emailed you before. I'll try to look for your email but just drop, drop it to me again. I'll stay, I'll stay for a few minutes in case any of you have any questions. But thank you so much for coming. Um And thank you. Thank you so much for tune ing in and responding to the polls do join us for our next session on ophthalmology. Next Tuesday. Another, a lot of more high yield stuff. I'll be doing that one as well. Um, so, yeah, enjoy your night. Have a good dinner. I'll stay for a few more minutes. So, don't worry. And if any of you want the, if any of you want the slides from the previous sessions and for some reason met all hasn't given any, hasn't given the slides to you. Um It could be because I, I think you have to attend to get the slides. But if you haven't, if you didn't attend, you can just email me and I can just, I can just send you the slides an easy way to remember G C S. Uh I just, to be honest, I just purely memorized it. I just remember um it's 456 and wait or is it 345? Uh Yes. Mission. Of course, you can, can you send me your email if that's fine? So how did, how did I remember gcs? Let's see. I have a quick look at my notes. Uh Okay, no problem. OK. So G C S it's E V M so I remember it as E V M 456. Okay. E eyes, V verbal and motor. So for eyes, I usually just, it's difficult because you sort of have to visualize what it is. So for eyes, it's like if it's open immediately, that's like a four. And then if they open to voice, that's a three. Open to pain, that's a two. And if they don't open it's a one so it can never be zero. It's always the one for the lowest thing. So the lowest you can get is three. So E V M 456. So these four and then V is five. Um, V is uh verbal. It's difficult. There's no easy way to remember it to be fair. Aisha, I think, I think you just have to sit down and sort of just remember, but I remember it. E V M 456. That's, that's how I remember it. Yes. No gum. Which slides do you want? Is there a specific side or do you want, do you want the slides for this one? Okay. Well, uh, um, if you wanted the slides for this one, as long as you're feeling the feedback forms, you should get the slides when I release it to you. If you wanted the slides from the previous one, which was general surgery, I can send you those slides if, if you, if you wanted to, if you can drop me your email. Mhm. Mhm. Mhm. For this one. Yeah. So don't worry. Um, as long as you fill in the feedback form, I'll send the slides out to everyone. So everyone should get the slides through Met. Also look for an email from Metal and then Metal should say you have access to catch up content and then the catch up content will, will send you, we'll send you to the slides for today. But if you don't get the slides, um, you can just email me or come to our next session. You can let me know if you, if you haven't, if you haven't gotten our, the slides for today and I can send you the slides there. Okay. Yep, I can definitely send you the general surgery one as well. Mhm. All right. So Naga Mation and Charmaine, I'll send the slides to you out, um, after this in a few minutes. But again, thank you so much guys for coming today. Um, if you don't get the slides from the emails, just, just email me again. Okay. And I can send the slides out to you guys. All right. Um All right. So I'm going to end this here. Thanks so much guys. Have a good evening. I'll see you guys on Tuesday. Nice.