Brain Meninges | Epidural, Subdural, Subarachnoid, & Intracerebral Hematomas

Alright Ninja Nerds, in this video we're going to talk about the types of intracranial hemorrhages. But before we do that, we have to have a good understanding of the normal anatomy of the meninges, okay? So the meninges are important because they're the actual connective tissue layers that cover the brain substance, the central nervous system, the brain and the spinal cord. So before we start going into the epidural and subdural and subarachnoid and intracerebral, let's get a good idea of what these meninges are, alright? In their order from, we're going to go from deep to superficial. Alright, and we'll talk about some spaces as we go along too, that are in between and that's where these bleeds are going to occur. So let's go ahead and get started. So first things first, just a little bit of orientation here. I'm taking a coronal section, right, a frontal or coronal section. And let's just say I'm taking it down the central sulcus, okay? So now what you're seeing is you're seeing that coronal section right here. So let's just pretend that this is the parietal lobe here, here's your temporal lobe, midbrain, pons, medulla, cerebellum. Right, simple as that. You have some deep nuclei inside of it like the thalamus, your lentiform nucleus, many different structures. We'll talk about them later. Big concept though is I want to represent each one of these and we're going to color coordinate everything. So the first layer as we go from deep to superficial, this is our brain substance here. So we're just going to say the first layer here that we're going to talk about is going to be the brain substance. So let's talk about that one first. Okay, so brain substance is this green layer right here. Now, there's a connective tissue that clings right to it. It actually clings. There's, you know, there's glial cells here called astrocytes. They have their foot processes. Well, the PM motor actually interacts with the foot process of those astrocytes on the brain substance. And they actually call it the pyoglial membrane. But we don't care about that. We care about specifically what is that connective tissue called. That connective tissue right there, this black connective tissue, It's called Pia Mater. So the next connective tissue after that right here is the Pia Mater. And Pia just stands for a soft mother. So Pia is the soft mater's mother. So soft mother. So a little soft connective tissue that clings to the brain and the spinal cord. After that, we go into this little space. You see this space right here? There's a space between this black tissue here and this blue tissue right there. The blue tissue is called the arachnoid mater and these little extensions are called trabeculae. We'll talk about that next. But there's a space right between this black line and this blue line. That space right there is called the subarachnoid space. Okay, so it is called the subarachnoid space. When we have a video specifically on cerebral spinal fluid flow, You'll see that that is where the cerebrospinal fluid is moving. Okay? So cerebrospinal fluid is moving inside of the actual subarachnoid space. Now, right after that, as we go continue more superficial, in this case up, we have this blue layer. This blue layer, we said, is called the arachnoid mater. Okay? So this blue layer is called the arachnoid mater. And again, mater is mother. Arachnoid is actually for arachnid. Basically, it's like a spider. So it looks like a spider mother. Okay? But what's important about this? The arachnoid mater, you see these little blue lines that are coming down? Those little blue lines are called trabeculae. They're little connective tissue partitions there. But what's really important, and we'll talk about this in a second, is you'll see the extension, the invagination of this arachnoid mater into this little like space right here. It's called a dural sinus. We'll talk about that too. But I want you guys to see all the parts of the arachnoid mater. So we have arachnoid mater with their trabeculae and these little extensions, which are called arachnoid granulations or arachnoid villi, and they're going to be kind of pushed into this dural sinus. Okay, after the blue layer, we have another space. There's a space between this blue line and this purple line. That space is called the subdural space. So then we have another one, which is called the subdural space. Subdural space. After the subdural space, then we have this purple layer. The purple layer is going to be a part of the dura mater, but there's two parts of the dura mater. One is the more inner layer. One is the inner one, so we're going to say it's called the inner, and we're going to say meningeal. So let's say inner layer, or we can also say the meningeal layer of the dura. Dura means tough, so it's a tough mother. So we have the inner meningeal layer of the dura mater, which is the purple layer. Then, right outside of that, there's another layer. It clings directly to this bone. I'm showing a space here, and there's a reason why for these bleeds. But this orange layer should be clinging to the bone. That orange layer is called the outer, or you can say the... Periosteal layer. So periosteum is a dense fibrous irregular connective tissue that's clinging to the bone tissue. So it's the periosteal layer of the dura mater. So there's two parts. So the dura mater is actually made up of two layers, an outer periosteal and an inner meningeal layer. Usually these are always sandwiched together. But in certain areas, in certain areas of the central nervous system, the inner meningeal layer branches away or breaks away from the periosteal layer. So you see this area right here? This space here right here is actually lined by endothelial cells. You know endothelial cells are important for lining our blood vessels like our arteries and our veins and stuff like that. Well there's veins that actually sit right here in this space and this space here is actually going to be where your dural sinuses run. We've talked about them before like the superior sagittal sinus, the inferior sagittal sinus, the petrosal sinuses, all of those guys, they run in these spaces right here. So again, what is this blue layer here called? Between these two, when it branches out between these two. Between these is going to be your dural sinus, which is basically veins. They're basically veins. So in here you're going to have some endothelial cells which are there. And if you remember, we said one of these are racks. granulations. If you know a little bit about your cerebrospinal fluid flow, you'll know that these arachnoid granulations or these arachnoid villi basically filter some of the cerebrospinal fluid out of the subarachnoid space and into these dural sinuses so they can get drained into the normal venous circulation. We'll talk about that when we do cerebrospinal fluid flow. But here's the big point I want to get across. The inner meningeal layer, when it breaks away, From the periosteal layer, there's a purpose for that because these dural sinuses, they're really thin. They can rupture very easily if there's a lot of trauma. But now we have this beautiful barrier around them. That beautiful barrier that's separating those two is really important. So I want us to understand that that barrier right there, like this, that's coming right here and then across, and then you're going to have your orange periosteal layer here. This right here is called a dural septa. And again, remember what sits right in here is going to be your dural sinus. But this structure here, which is surrounding the dural sinus, is called your dural septa. These are important. There's actually three types that I want you guys to know about. One is called the falx cerebri. Another one is called the tentorium cerebelli. And then one more minor one which is called the Faux Cerebelli. These are dural septa partitions where the inner meningeal layer branches away from the outer periosteal layer and surrounds dural sinuses. For example, the Faux Cerebrae, you can find that running right here. This would actually be the Faux Cerebrae. It's right where the longitudinal fissure is. It sits right in there and protects the superior sagittal sinus. The tentorium. Ptitorium cerebelli is actually going to be right in the transverse fissure between the occipital lobe and the cerebellum. And it actually separates the cerebellum and the actual cerebrum apart. That's an important one. There's some sinuses that run within this one too. The Falk cerebellum actually kind of runs right within the vermis of the cerebellum. And it also protects certain types of venous sinuses. There's one other one which actually is going to be right around the cellotersica. They call the diaphragm cellae. Not a super important one, but again, there is another one, which is called the diaphragm cellae, right around the cellotursica of the sphenoid bone. But a big purpose here, big, big takeaway, is these dural septa, what is their purpose? To surround and protect those dural sinuses, which are basically acting like veins. So we covered that. So now, we got to talk about this next thing. So here is our bone, right? There's the bone of the skull, right? Now, in between the bone of the skull, right? And this dura mater, we said there's a space, but that's technically not true. They call it potential space. So there's a potential space in the... actual cranium between the skull bone and the dura mater. That potential space is called the epidural space. There's a reason why I'm drawing all of these in red because that's where the hemorrhages are occurring. Alright, now after that what we have we'd have the bone of the skull. So we have the epidural space which is that potential space then we'll have the skull bone. And then after that you'll have the scalp. So you have the different parts of the scalp. You'll have specifically the skin, then you'll have after that, you'll have some connective tissue structures, the gallia aponeurotica. Around here we're talking about the actual part of the skull, the top of the skull. But again, skull bone, and then the last part here should be the scalp. Okay? Last part here should be the scalp. So now we've just covered all the layers from the brain substance all the way to the scalp. And we should now understand these layers very, very well. Now let's go ahead and dig in to all the hemorrhages that could possibly occur, starting first with the epidural hemorrhage. Okay? So if someone has an epidural hematoma, so the first one we're going to talk about is an epidural hematoma. Okay? Now, epidural hematoma, we have to talk about a couple things. We want to talk about their location, the mechanism by which this hematoma can form. We want to talk about the symptoms, some of the symptoms that can come about. How would you diagnose it? And then generally, how would you manage the patient who has this type of situation? All right, so first off, epidural hematoma, we already know where it's going to occur. In the epidural space. So we know it's going to be occurring specifically in the epidural. Space. That's pretty much obvious. That's why laying down the groundwork for these meninges and layers is so easy. But now we've got to dig into it a little bit more. What areas of the skull are most commonly affected by this type of hemorrhage? Well, generally, let's just say it's right here. Let's say here I'm going to have some bleeding here. There's going to be some bleeding right here. And this bleed that's going to accumulate in this epidural space is going to occur at a specific location. You know right around the temporal bone they have this area called the terion and that bone is kind of thin there. So if there's some type of like blunt force trauma that fractures that bone and it actually lacerates the arteries that are running in between that epidural space that could be a really really bad problem. So now specifically we know it occurs in the epidural space which is potential space but we also should know where exactly is it occurring around the skull. So specific area is going to be a temporal fracture. So temporal bone fracture. Now, the temporal bone fracture, right around the, specifically let's say around the terion. Specifically around the terion. Now the next question is how does this actual bone fracture cause a bleed? Well you know if we have like a little mini diagram right here. Let's say here I have a mini diagram. I have anterior cranial fossa, middle cranial fossa, posterior cranial fossa. Just like this foramen magnum and we come back up here, right? You have a little hole right here in the skull called the foramen spinosum. And the foramen spinosum is where this artery runs up through. You know there's the common carotid artery? So pretend here we have the common carotid artery. That splits into the external carotid artery and the internal carotid artery. Well the external carotid artery gives off a branch called the maxillary artery. And from the maxillary artery, this middle meningeal artery runs up through the foramen spinosum and in between that epidural space, that potential space, if you will. So now, if I fracture the temporal bone, what am I going to do? I'm going to lacerate those middle meningeal arteries. So now, we know that the location is going to be the epidural space, like the actual temporal bone fracture, and we know that we're going to lacerate specifically the middle. Meningeal arteries. And that's bad. So now the blood is going to accumulate here. And what happens is, if we imagine like this, look at this. As the blood accumulates here, look what it's going to do. The blood is going to start really, really accumulating here, and it's going to form a biconvex type of lens-like shape. And what happens is because this part here These types of hematomas, they generally don't actually spread across the, you know, the sutures of the skull. You have the sutures of the skull. For example, like sagittal suture, or you can have the coronal suture, the squamous suture, the lambdoid suture, all these sutures. What happens is, is right here you can have this biconvex type of structure here. And this is bad because look what it's doing. It starts pushing down on the brain substance. As you push down on the brain substance, what can that cause? You know, whenever you push down on the brain, you're gonna try to herniate the brain and that could be a very very bad thing because her brain herniation can basically very very quickly lead to coma or Possibly death so then what you're gonna see here when you take them To a CT you'll see it. You'll do a CT of their actual skull or your head CT and you'll see this Biconvex or lens shaped type of hematoma. All right, that's what you'll see here. So We'll talk about, we'll write that down afterwards, but this is what I want you guys to see. You're going to see this biconvex or lens-shaped hematoma. Now, next question you should ask, what symptoms are they going to be showing? Well, generally, when someone has this type of hematoma formation, most commonly because of the intracranial pressure, they're going to show signs of a headache. They're going to show signs of a headache, even some nausea. We're going to put in for nausea, some nausea, some vomiting. And on top of that, they might even have focal neural symptoms. What does that mean? Depending upon the area that this mass is accumulating in, it can compress the brain substance and affect the normal function of that actual cortical tissue. So it can cause focal neural symptoms. What else would you see from these patients? Well, here's another thing. As these patients start having these masses, it starts trying to push down. on the actual brain substance, right? There's a specific lobe, your medial temporal lobe, it's called the uncus. As these epidural hematomas accumulate, they push and push and push down on that uncus to the point to where it tries to herniate out through what's called the tentorial notch. Remember what we call the tentorium cerebelli? Look, imagine here I have it going like this. Here's one part of the tentorium cerebelli, here's the other one, right? And again, what's it doing is it's separating the cerebellum from the actual cerebrum. There's a little hole here called the tentorial notch. And what happens is a part of the actual brain substance can herniate through that area there. And that's what actually happens. So if someone gets what's called a tentorial herniation, it can actually compress a specific nerve that runs right in that area. You know the third cranial nerve? It runs right through that area. So sometimes you might even see the person having a third nerve palsy. And if you guys have watched our video on the third cranial nerve, you'll know what those signs are. You know that it actually is going to cause a down and out movement and might even cause pupillary dilatation. Okay? All right. Now, something else that you're going to want to look at is going to be the diagnosis, right? So whenever you're trying to diagnose the patient here, you're going to try to do a head CT. So you want to do a head CT. Okay, so you're going to want to do a CT scan of the head. So do a CT of the head. When you do the CT of the head, what do we say it's going to come back with? This biconvex or lens-shaped hematoma. But what did I tell you? It doesn't cross the sutural ligament line. So when you do a CT of the head, you're going to see a, we're just going to say a lens-shaped hematoma. And again, what do we say? It doesn't cross suture lines. That's important. That's going to be one of the defining factors between that and a subdural hematoma because they actually can cross the suture lines. Okay, so now we know if we're looking at this patient, we're going to see these basic signs. Now the next question you should have is how do we manage it? What do we do? Well, You can actually do what's called a craniotomy or a burr hole and evacuate the mass. You can actually drill right through here and drain the actual blood or the hematoma. So that's one thing you can do, but it depends. If the intracranial pressure is really high that they're at risk of having a brain herniation, then yeah, you're going to want to evacuate the hematoma. So first thing you're going to want to try to do is evaluate the patient, see if it's necessary to evacuate the hematoma. All right, now... If they do have, sometimes because of this, when you're going to have to put in this type of hematoma. So next thing, if we evacuate the hematoma, that's usually because of some type of serious issue. That's necessary. Depending upon how large it is, you're increasing the risk of brain herniation. But sometimes we might not have to evacuate the hematoma. Sometimes we just might have to maintain. in the person's intracranial pressure. And the ways that you can do that, well, first thing, depending upon if there is cerebral edema, you can give them something called mannitol, and you can give it IV. And what that's going to do is it's going to decrease the cerebral edema in the area. Another thing you can do is you want to elevate their head. So elevating their head can also help in this process. Or even putting shunts in, sometimes putting a shunt into the area and draining it, that's been found to help. But sometimes there can be some minor complications when you're doing that. And another thing that you can also do besides the mannitol, elevation, or shunt is they find this to be helpful sometimes is hyperventilating the patient. Hyperventilating the patient has been found to be able to stabilize the intracranial pressure. Okay? So now we go into the next one. The next type of bleed is going to be right after. So epidural space, subdural space. So what do you think this one's called? This one is going to be called the subdural hematoma. So this next one here is going to be subdural. Subdural hematoma. Subdural hematoma. Where does it occur? What's the location? Subdural space. Keep it simple there. Subdural space. Now, the next thing that you should ask yourself, we know it occurs in the subdural space. The subdural space is going to be where again? It's going to be in between the arachnoid mater and the inner meningeal layer of the dura mater. Now the next thing that you should ask yourself is now the locations they can vary. It can honestly vary from person to person depending upon the type of situations that this occurs. Because subdural hematomas they can be very very severe depending upon if it's an acute or chronic type of hematoma. Acute is like if someone actually gets up in a motor vehicle accident or if they've had a severe trauma like blunt force trauma to the head or if they are older. Sometimes as people get older. their brain atrophies and it's easier whenever there's very very Sudden shifts within the brain it can actually tear or shear certain types of bridging veins Okay, so subdural hematomas occur in the subdural space and the locations vary Okay, but what's the mechanism what we said could be due to a motor vehicle accident? I'm gonna put MVA could be due to some type of trauma right and another thing is it could be due to Falls And again, the falls are a little bit more common with the older individuals because as they get older, their brain atrophies, which allows for the brain to move a little bit more inside of the actual spaces. And remember, the cerebral spinal fluid allows for the brain to float. It provides buoyancy. But with very, very sudden movements, acceleration, deceleration, it can shear specific types of veins that run through that space. What are those veins called? Those veins are called your bridging veins. So they're called your cortical. Bridging veins. So what happens is during these, like pretend you're in a motor vehicle accident. So you're driving at about 60 miles an hour all of a sudden you hit a truck, right? What happens? Your head moves forward and then it comes back. Usually this causes a counter coupe type of a reaction and because of that the movement forward and backward stretches those bridging veins and then shears them and that's what becomes so bad. So shearing of the bridging veins is usually in the mechanism by which it causes a subdural hematoma. These are usually the most fatal. Out of the home hematomas, this is one of the most fatal if it's acute. The person can die very, very quickly if not treated properly. Now, symptoms. These ones, again, it can vary. It really does. It varies a lot from person to person. But generally, whenever you see someone with some type of intracranial bleed, Usually they're going to have headaches. Because signs of intracranial pressure is usually headaches, vomiting, their blood pressure changes. Here's a good way to remember, because sometimes people will switch them up. Think about shock. In patients who have shock, what happens? Their blood pressure drops, their heart rate goes up, their pulse goes up, and their respirations change also. So whenever you're seeing someone in shock, you think about their blood pressure. Theirs goes what? down. So in a person with intracranial pressure, they're going to have a high BP. Also think about their pulse. Well, a person who is in shock is going to have what? They have a high pulse. So this person would actually have a low pulse. And you might even see the person due to this type of situation, they might even have some type of confusion. Okay. They might have some confusion or a loss, not loss of, they can't actually lose consciousness, but it depends upon the severity. That reminds me of something. With epidural hematomas, what I want you guys to remember for the symptoms here, this is honestly the most important thing to be able to differentiate these two. With epidural hematomas, This is super big. They can lose consciousness. So LOC, they can have loss of consciousness. But then when they lose consciousness, some of the patients, after they gain or they actually go back, they actually gain consciousness, right? They can act absolutely normal. Their vitals can basically go back to stable levels. They can be normal. That is called a lucid interval. But then here's the big thing. If these patients exhibit a lucid interval, Most commonly right after that lucid interval the patient starts declining very suddenly and very rapidly and they can even go into a comatose state or depending upon the severity death. So that's one of the big things that I want to definitely make sure you guys understand to differentiate this point here is that epidural hematomas show loss of consciousness with a lucid interval where they basically their vitals go back to normal They're acting like everything is okay, but then all of a sudden they start declining very, very rapidly. People with subdural hematomas, they generally don't show any signs of any lucid interval. That's an important thing to remember. Okay, so we got the symptoms. We know that it can vary, but generally headaches, blood pressure changes, like increasing, decreasing pulse, confusion. And like anything, because of it, it can even cause some nausea and some vomiting too. Now how would you diagnose the patient? You send them to CT. Again. You're going to do a CT scan for pretty much all of these. But send them to do a CT scan. So you do a CT of the head. When you do a CT of the head, what are you going to see? Okay, well let's come over here. Let's get my red marker here. So again, what was the space right here? Right here. What you're going to see is you're going to see blood is going to occupy this area here. And when it does, it occupies this subdural space. The bleed that it, the shape that this bleed makes is usually going to be crescent shaped. or concave in shape. So you see how it kind of forms this concave shape or this crescent shape structure? That's important because what it can do again with any of these bleeds is it can accumulate here and start pushing down on the brain substance. And as it starts pushing down on the brain substance, this can increase the intracranial pressure. So this is kind of what you would see in this patient like this. Okay, so when you do a CT of the head, You do a CT and you'll see that the patient will most likely have a crescent or we can say concave hematoma. And what did I tell you guys? The epidural did not cross the suture lines. This one can cross suture lines. Okay? Now, next thing. We did a CT. We verified that they did have a bleed. They have a subdural hematoma. The next question we should say is, what the heck do we do? Well, these are bad. The reason why is, let me come back over here for a second. These crescent-shaped bleeds, right, that you see over here, they can start pushing the brain substance. Because they can spread past the suture lines, they can start pushing the brain substance to one side. And as they start pushing the brain substance to one side, what do you think is going to happen? It's going to shift. the midline of the brain. Imagine I make a vertical asthmatoid right here. The vertical asthmatoid should be right here, but as this brain substance starts pushing and pushing and pushing, it starts shifting the midline. If the midline shifts greater than, if they have a midline shift greater than five millimeters. So if there is a midline shift greater than five millimeters, we need to evacuate the hematoma. Okay, so if they have a midline shift greater than 5 millimeters, this is necessary. The protocol would be to evacuate the hematoma. Okay, so that is going to take care of our subdural hematomas. Now we go to the next one, subarachnoid. Subarachnoid hematomas, these are also very, very, very bad. They're all very bad. I mean, they all have their own thing, right? Subdural, I'm sorry, subarachnoid hemorrhages. Subarachnoid hemorrhages, where do you think that these bad boys are going to occur? In the subarachnoid space. So now we're going to have the subarachnoid hematoma. And again, the subarachnoid hematoma, where do you think it's going to be occurring? It's going to be occurring right here within the subarachnoid space. Okay? So again, where's the subarachnoid space? Remember, it's in between the pia mater and the arachnoid mater. Okay? Now, we know again, where is it going to occur? In the subarachnoid space. Now, the mechanism. Generally, this is most commonly due to berry aneurysm ruptures. So most commonly due to berry aneurysms, or they also call them saccular aneurysm ruptures. What the heck is a berry aneurysm? You know, the circle willis, if you guys remember. You have the circle of willows. We're not going to go through the whole thing, but I just want you guys to remember a basic thing here. Pretend here we have, for a second, we have anterior cerebral arteries, right? And then you have your anterior communicating arteries. We'll get those in a second. And then you have your middle cerebral arteries. You have your posterior communicating arteries, posterior cerebral arteries, right? And again, feeding these is the internal carotid. Feeding these is the internal carotid. And then let's just make this special here. We're going to say this is the posterior communicating artery right here, and these are your anterior communicating arteries. What happens is, is for people, they actually can, it can be due to genetic conditions, like Ehlers-Danlos Syndrome or Marfan Syndrome, whatever it might be. The blood vessels, if you guys watch our tunic layers, they have a tunica interna or an intima. Outside of that, they have another layer, and there's this like elastic tissue. It's called the elastic lamina. You know the internal and external elastic lamina? As people are due to hypertension or due to connective tissue disorders, this tissue, this elastic lamina, can decrease. So as the elastic lamina concentration decreases, what happens as pressure is actually coming out here? Because the purpose of the elastic lamina is to accommodate stretch but recoil and assume the normal size. But if you're decreasing the concentration of this, whenever it's stretched, it won't be able to return to the normal size. And so what happens is it forms like a little balloon. And this little balloon that you're going to see here is called an aneurysm, right? So because of the decrease in this elastic lamina tissue, it can cause these bulgings of the actual blood vessel wall. And what happens is as this continues and continues, guess what it can do? It can rupture and blood can start spewing out. Where do you think it spews out? Right into the subarachnoid space. Now, let's write that down. So, barianeurism, saccular aneurysms are usually, if you wanted to remember the most common areas, it's usually due to the anterior communicating arteries. That's usually the most common. So, the anterior communicating arteries or the middle cerebral artery. There's also another one. So, the middle cerebral artery, the anterior communicating arteries, those are usually the most common ones that can actually rupture. So, what are some of the symptoms? Now, this person. is going to have a headache like they've never had in their entire life. So they are going to have, they actually call it like the thunderclap headache. Thunderclap headache. It's going to be excruciating headache. They say it's the worst headache they've ever had in their entire life. Sometimes it can be unilateral, sometimes not. Sometimes it can even radiate to the occipital region too. Now another thing that you're going to see with this person is they're going to have some signs of nausea, some vomiting also. But these patients usually don't show any, no focal neurological symptoms, which is good, but they don't show any focal neurological symptoms generally. But what you will see in this patient is they're going to start showing meningeal symptoms. What do I mean? When someone has like meningitis, they show neck stiffness. And sometimes you can see that when you do like the Koenig's test or the Brzezinski's test and stuff like that. But these people will have a lot of neck stiffness. Another thing is they'll be very sensitive to light. Photophobia. All right, so they'll have photophobia. And they might start losing it, man. They might start actually becoming delirious. So another thing that you might see within these patients is they might start showing signs of delirium. So what are you going to see? Thunderclap headache, nausea, vomiting. It can actually be unilateral or not. It can radiate to the occipital region. They might have some neck stiffness and photophobia and delirium, which are basically meningeal symptoms. But again, they don't usually show any focal neurological symptoms, which is interesting, right? Now, how would you diagnose it? CT scan. So send them to CT. That's your first thing, right? Do a CT of the head. Now, when you do the CT of the head, here's what you want to look for. You want to see a bleed within the subarachnoid space. But here's the important thing. If the CT is positive, okay, here's the important thing. If the CT is positive for a subarachnoid hemorrhage, Then you send them to do the gold standard, basically, which is a four-vessel angiography, where they go in and they determine where the actual vessel, the aneurysm ruptured. Okay? That's a good way to completely confirm that they had a subarachnoid hemorrhage. So if you do a CT and you think that you saw a bleed, you send them to do a four-vessel angiography. But here is the key. You don't do the lumbar puncture if you think that they might have it. Okay? You do that if it's negative. So if the CT is negative, then you do a lumbar puncture. If you do the lumbar puncture, what are you looking for? Usually you'll have what's called xanthochromia. Xanthochromia. It's a yellowish pigment. This is usually a sign that the person has red blood cells in their cerebral spinal fluid. Another thing that you want to see is... Check their cerebrospinal fluid pressure, their opening pressure. So you'll check the cerebrospinal fluid pressure, and if it's high, that's also showing signs of maybe high intracranial pressure, okay? How would you manage this person? This one, there's new techniques that they do now. Well, first off, if it's not as bad, let's say it's not bad. Let's say it's not a really, really bad one. You can give supportive care, okay? And supportive care, basically for this, you do... You'll do bed rest, you'll do stool softeners. What else would you do? Another thing that they can do for the patient is they can give them medication to lower their blood pressure gradually. So you want to lower their blood pressure gradually. So you give them a bunch of different types of drugs. You can give them, you know, they give labetalol. Labetalol is an alpha and beta adrenergic blocker. So you can give them labetalol. There's another drug that you can give which is nicartapine. So you can give nicartapine or you can give another one which is called nemotapine. And again, I'll just put it here. These are alpha and beta blockers. And these two are calcium channel blockers. And again, the whole purpose of these is just basically to lower the blood pressure gradually. Now, the next thing I want to tell you guys. So if we do supportive care, if it's not that bad, what if it is really bad? They have these new techniques now that are just unbelievable. So what they do is they actually take, let's pretend we have that aneurysm over here. Again, we come back over here. They take like a little catheter basically. They feed it up through your femoral vein. And what they do is this catheter, it comes up here to where the aneurysm is. And they inject out here this surgical coiling like structure. So they do what's called surgical coiling. They used to do clipping where they come in there and they clip that off, but it was just, it was too invasive. So they found different ways to do this, getting very, very good results without having to have that such of an invasive effect. So what they can do is they go in here and they actually insert this little cat, this actual coil. It's called an endovascular coil. And the endovascular coil will basically block off the blood flow to the area, which prevents the rupturing of that vessel. Okay, so that's one way that they can do that is they can actually do what's called an endovascular coiling or clipping. So again, over here, if you want to remember, if it's severe, they can do coiling, which is the preferred method nowadays, or clipping, which is the more invasive one, of the aneurysm. And your is okay. All right. So we got that. Now we have the last and final one. The last and final one that we're going to do here is going to be the intracerebral. So the last one here is going to be the intracerebral. So intracerebral hemorrhages, there is many types, right? There's actually a bunch of different types and we're going to hit the basis of it. We're not going to go super super intense. We're going to hit what we need to know this, right? So intracerebral hematomas. Location. Let's hit the basic locations. So let me go ahead and get this stuff out the way because I actually need this now. There's a couple different areas. We're going to hit the most common ones. There's so many areas, but we're going to hit the basic ones. If you guys remember, we've talked about it a couple times. You know you have an artery right here. It's called the middle cerebral artery, right? Well, the middle cerebral artery gives off these branches, okay? It gives off... These branches that come over here and supply this nucleus. You know what this nucleus over here is called? They call this nucleus the lentiform nucleus. They call it the lentiform nucleus. So these arteries, they're actually going and supplying a lot of these different structures of the lentiform nucleus, the basal ganglia. What can happen is if people who have, there's a bunch of different causes. But if they have certain types of arteriovenous malformations, they might even have aneurysms here, they might even have amyloidosis. So there's many different causes. Hypertension is another cause here. These vessels rupture. When they rupture, what is the name of these vessels actually? That's what we should know. What is the name of these vessels? This is called the lenticulostriate. Artery, arteries. If these are affected, it affects the lintiform nucleus, like the putamen, the globus pallidus, externus and internus. It can even affect some of the other structures like the caudate nucleus. And this can cause some really, really bad problems. So there's one type of hemorrhage. Another one is you have these arteries here, these arterial branches. And these arterial branches that are going to the thalamus, these are actually called jaw. geniculate arteries. These are called your thalamogeniculate arteries. If these, due to hypertension, amyloidosis, or some type of arteriovenous malformation, they actually rupture, it can cause a bleed that's affecting the thalamus. What other structures? Well, remember, we also had, if you guys go back and remember, we have the vertebral arteries here. And the vertebral arteries come together and form what's called the bacillar artery. And the bacillar artery is giving off these little branches here to the pons, right? They call them the pontine branches or they can even call them the paramedian pontine branches. If these are affected due to hypertension, amyloidosis, arteriovenous malformations, it can affect the pons. What other areas? You know there's other areas over here too where you can have effects. There's the cerebellum. You know there's a bunch of different arteries that are going to be going to the cerebellum. Remember we had the anterior inferior cerebellar artery and the posterior inferior cerebellar artery. There's even the other ones like the superior cerebellar artery. If for some reason due to hypertension, arteriovenous malformation, amyloidosis, these rupture, it can cause a bleed within the cerebellum. So what locations are we going to find these suckers in? We can find bleeds within the thalamus. We can find bleeds within the basal ganglia, we'll just say, like the lintiform nucleus, the globus pallidus, the caudate nucleus. We can find it also within the cerebellum, and we can find it within the pons. Now, what's the mechanism? Again, we said it's usually due to some type of... Bleed due to hypertension. So hypertension is one common cause here of those blood vessels that we mentioned. Another one is an AVM, an arteriovenous malformation. We talked about this in microcirculation when there's basically a big, the flow of blood in a capillary bed doesn't go through the capillaries. It goes through a big arterial to venial connection which causes the pressure to build up and it can rupture. Another one is amyloid deposits. as we said, right? So amyloid deposits. All of these things can basically be the mechanism by which those vessels can rupture. What type of symptoms would you see? Again, basically you're going to see headache, nausea, vomiting. Another thing this person might actually have is you're going to actually see that they can have, depending upon the areas that affected, is they might have hemiparesis. So they might have this loss of sensation. They might even have the loss of motor tone. which we call hemiplegia, right? They can have these types of symptoms too. And depending upon how severe the injury is, they might even have a brief loss of consciousness too, okay? How would you diagnose the patient? Again, you're going to do a CT of the head. So do a CT of the head. See if you can find some type of intraparenchymal bleed via the thalamogeniculate arteries, the lenticular striate, the paramedium pontine. Superior cerebellar, anterior inferior cerebellar, posterior inferior cerebellar arteries. If you see those, okay. Most likely they have some type of intracerebral bleed. Here's the thing. Goes back to this thing up here, but with subarachnoid. If you suspect that they might have an intracerebral bleed, do not do lumbar puncture. You could kill the patient. You could cause their brain to herniate because of the high intracranial pressure. So do not do a lumbar puncture if you suspect that the person might have an intracerebral hematoma. This is a no-go. If you think that they might have it based upon looking at the CT scan, how would you manage it? Well, again, if it's the problem with the intracranial pressure, if they have high intracranial pressure, give them the mannitol. The mannitol is going to help to decrease some of that cerebral edema, decreasing that actual intracranial pressure. Another thing that you can do is depending upon sometimes because of these structures here because of These arteries if they actually start causing Compression here or compression here or compression on some of the nuclei here Compression on some of the cerebellar structures here it can start causing a lot of problems and they call that when it's starting Compressing the brain substance. It's called mass effect if you see If mass effect is evident, evacuate the hematoma. Okay? Now that intracranial pressure is a bugger, man. And here's another thing. One last thing that I want to say before we finish up is when you do the subarachnoid hemorrhages, one other thing that you can do is when you do ophthalmoscopy, you look into the actual retina, if you see that the patient has retinal hemorrhaging, This is called Turson's Syndrome. So look to see. Another thing about the subarachnoid hemorrhage is if you see that the person might have retinal hemorrhaging, that might be another telltale sign for a subarachnoid hematoma. All right, Ninjas and Nerds, so that pretty much tells you guys everything that you would need to know about these intracranial hemorrhages. I really hope it made sense. I truly do. That is our true, true desire to make this stuff make sense for you guys. If it did, please, I'm begging you, hit that like button, comment down in the comment section, and please subscribe. hit the subscribe button. All right, guys, please also, if you guys get a chance, check out our Instagram, our Facebook, and even our Patreon account. All right, engineers, as always, until next time.

In their order from, we're going to go from deep to superficial. Alright, and we'll talk about some spaces as we go along too, that are in between and that's where these bleeds are going to occur. So let's go ahead and get started.

So first things first, just a little bit of orientation here. I'm taking a coronal section, right, a frontal or coronal section. And let's just say I'm taking it down the central sulcus, okay? So now what you're seeing is you're seeing that coronal section right here.

So let's just pretend that this is the parietal lobe here, here's your temporal lobe, midbrain, pons, medulla, cerebellum. Right, simple as that. You have some deep nuclei inside of it like the thalamus, your lentiform nucleus, many different structures.

We'll talk about them later. Big concept though is I want to represent each one of these and we're going to color coordinate everything. So the first layer as we go from deep to superficial, this is our brain substance here.

So we're just going to say the first layer here that we're going to talk about is going to be the brain substance. So let's talk about that one first. Okay, so brain substance is this green layer right here.

Now, there's a connective tissue that clings right to it. It actually clings. There's, you know, there's glial cells here called astrocytes. They have their foot processes. Well, the PM motor actually interacts with the foot process of those astrocytes on the brain substance.

And they actually call it the pyoglial membrane. But we don't care about that. We care about specifically what is that connective tissue called.

That connective tissue right there, this black connective tissue, It's called Pia Mater. So the next connective tissue after that right here is the Pia Mater. And Pia just stands for a soft mother. So Pia is the soft mater's mother.

So soft mother. So a little soft connective tissue that clings to the brain and the spinal cord. After that, we go into this little space.

You see this space right here? There's a space between this black tissue here and this blue tissue right there. The blue tissue is called the arachnoid mater and these little extensions are called trabeculae.

We'll talk about that next. But there's a space right between this black line and this blue line. That space right there is called the subarachnoid space.

Okay, so it is called the subarachnoid space. When we have a video specifically on cerebral spinal fluid flow, You'll see that that is where the cerebrospinal fluid is moving. Okay? So cerebrospinal fluid is moving inside of the actual subarachnoid space. Now, right after that, as we go continue more superficial, in this case up, we have this blue layer.

This blue layer, we said, is called the arachnoid mater. Okay? So this blue layer is called the arachnoid mater.

And again, mater is mother. Arachnoid is actually for arachnid. Basically, it's like a spider.

So it looks like a spider mother. Okay? But what's important about this?

The arachnoid mater, you see these little blue lines that are coming down? Those little blue lines are called trabeculae. They're little connective tissue partitions there. But what's really important, and we'll talk about this in a second, is you'll see the extension, the invagination of this arachnoid mater into this little like space right here.

It's called a dural sinus. We'll talk about that too. But I want you guys to see all the parts of the arachnoid mater.

So we have arachnoid mater with their trabeculae and these little extensions, which are called arachnoid granulations or arachnoid villi, and they're going to be kind of pushed into this dural sinus. Okay, after the blue layer, we have another space. There's a space between this blue line and this purple line. That space is called the subdural space. So then we have another one, which is called the subdural space.

Subdural space. After the subdural space, then we have this purple layer. The purple layer is going to be a part of the dura mater, but there's two parts of the dura mater.

One is the more inner layer. One is the inner one, so we're going to say it's called the inner, and we're going to say meningeal. So let's say inner layer, or we can also say the meningeal layer of the dura.

Dura means tough, so it's a tough mother. So we have the inner meningeal layer of the dura mater, which is the purple layer. Then, right outside of that, there's another layer. It clings directly to this bone. I'm showing a space here, and there's a reason why for these bleeds.

But this orange layer should be clinging to the bone. That orange layer is called the outer, or you can say the... Periosteal layer. So periosteum is a dense fibrous irregular connective tissue that's clinging to the bone tissue.

So it's the periosteal layer of the dura mater. So there's two parts. So the dura mater is actually made up of two layers, an outer periosteal and an inner meningeal layer. Usually these are always sandwiched together.

But in certain areas, in certain areas of the central nervous system, the inner meningeal layer branches away or breaks away from the periosteal layer. So you see this area right here? This space here right here is actually lined by endothelial cells. You know endothelial cells are important for lining our blood vessels like our arteries and our veins and stuff like that.

Well there's veins that actually sit right here in this space and this space here is actually going to be where your dural sinuses run. We've talked about them before like the superior sagittal sinus, the inferior sagittal sinus, the petrosal sinuses, all of those guys, they run in these spaces right here. So again, what is this blue layer here called?

Between these two, when it branches out between these two. Between these is going to be your dural sinus, which is basically veins. They're basically veins.

So in here you're going to have some endothelial cells which are there. And if you remember, we said one of these are racks. granulations. If you know a little bit about your cerebrospinal fluid flow, you'll know that these arachnoid granulations or these arachnoid villi basically filter some of the cerebrospinal fluid out of the subarachnoid space and into these dural sinuses so they can get drained into the normal venous circulation.

We'll talk about that when we do cerebrospinal fluid flow. But here's the big point I want to get across. The inner meningeal layer, when it breaks away, From the periosteal layer, there's a purpose for that because these dural sinuses, they're really thin.

They can rupture very easily if there's a lot of trauma. But now we have this beautiful barrier around them. That beautiful barrier that's separating those two is really important. So I want us to understand that that barrier right there, like this, that's coming right here and then across, and then you're going to have your orange periosteal layer here.

This right here is called a dural septa. And again, remember what sits right in here is going to be your dural sinus. But this structure here, which is surrounding the dural sinus, is called your dural septa. These are important.

There's actually three types that I want you guys to know about. One is called the falx cerebri. Another one is called the tentorium cerebelli.

And then one more minor one which is called the Faux Cerebelli. These are dural septa partitions where the inner meningeal layer branches away from the outer periosteal layer and surrounds dural sinuses. For example, the Faux Cerebrae, you can find that running right here.

This would actually be the Faux Cerebrae. It's right where the longitudinal fissure is. It sits right in there and protects the superior sagittal sinus. The tentorium.

Ptitorium cerebelli is actually going to be right in the transverse fissure between the occipital lobe and the cerebellum. And it actually separates the cerebellum and the actual cerebrum apart. That's an important one. There's some sinuses that run within this one too. The Falk cerebellum actually kind of runs right within the vermis of the cerebellum.

And it also protects certain types of venous sinuses. There's one other one which actually is going to be right around the cellotersica. They call the diaphragm cellae. Not a super important one, but again, there is another one, which is called the diaphragm cellae, right around the cellotursica of the sphenoid bone. But a big purpose here, big, big takeaway, is these dural septa, what is their purpose?

To surround and protect those dural sinuses, which are basically acting like veins. So we covered that. So now, we got to talk about this next thing. So here is our bone, right?

There's the bone of the skull, right? Now, in between the bone of the skull, right? And this dura mater, we said there's a space, but that's technically not true.

They call it potential space. So there's a potential space in the... actual cranium between the skull bone and the dura mater.

That potential space is called the epidural space. There's a reason why I'm drawing all of these in red because that's where the hemorrhages are occurring. Alright, now after that what we have we'd have the bone of the skull.

So we have the epidural space which is that potential space then we'll have the skull bone. And then after that you'll have the scalp. So you have the different parts of the scalp.

You'll have specifically the skin, then you'll have after that, you'll have some connective tissue structures, the gallia aponeurotica. Around here we're talking about the actual part of the skull, the top of the skull. But again, skull bone, and then the last part here should be the scalp.

Okay? Last part here should be the scalp. So now we've just covered all the layers from the brain substance all the way to the scalp.

And we should now understand these layers very, very well. Now let's go ahead and dig in to all the hemorrhages that could possibly occur, starting first with the epidural hemorrhage. Okay?

So if someone has an epidural hematoma, so the first one we're going to talk about is an epidural hematoma. Okay? Now, epidural hematoma, we have to talk about a couple things. We want to talk about their location, the mechanism by which this hematoma can form.

We want to talk about the symptoms, some of the symptoms that can come about. How would you diagnose it? And then generally, how would you manage the patient who has this type of situation?

All right, so first off, epidural hematoma, we already know where it's going to occur. In the epidural space. So we know it's going to be occurring specifically in the epidural.

Space. That's pretty much obvious. That's why laying down the groundwork for these meninges and layers is so easy.

But now we've got to dig into it a little bit more. What areas of the skull are most commonly affected by this type of hemorrhage? Well, generally, let's just say it's right here.

Let's say here I'm going to have some bleeding here. There's going to be some bleeding right here. And this bleed that's going to accumulate in this epidural space is going to occur at a specific location.

You know right around the temporal bone they have this area called the terion and that bone is kind of thin there. So if there's some type of like blunt force trauma that fractures that bone and it actually lacerates the arteries that are running in between that epidural space that could be a really really bad problem. So now specifically we know it occurs in the epidural space which is potential space but we also should know where exactly is it occurring around the skull. So specific area is going to be a temporal fracture.

So temporal bone fracture. Now, the temporal bone fracture, right around the, specifically let's say around the terion. Specifically around the terion.

Now the next question is how does this actual bone fracture cause a bleed? Well you know if we have like a little mini diagram right here. Let's say here I have a mini diagram.

I have anterior cranial fossa, middle cranial fossa, posterior cranial fossa. Just like this foramen magnum and we come back up here, right? You have a little hole right here in the skull called the foramen spinosum.

And the foramen spinosum is where this artery runs up through. You know there's the common carotid artery? So pretend here we have the common carotid artery. That splits into the external carotid artery and the internal carotid artery.

Well the external carotid artery gives off a branch called the maxillary artery. And from the maxillary artery, this middle meningeal artery runs up through the foramen spinosum and in between that epidural space, that potential space, if you will. So now, if I fracture the temporal bone, what am I going to do?

I'm going to lacerate those middle meningeal arteries. So now, we know that the location is going to be the epidural space, like the actual temporal bone fracture, and we know that we're going to lacerate specifically the middle. Meningeal arteries. And that's bad.

So now the blood is going to accumulate here. And what happens is, if we imagine like this, look at this. As the blood accumulates here, look what it's going to do. The blood is going to start really, really accumulating here, and it's going to form a biconvex type of lens-like shape. And what happens is because this part here These types of hematomas, they generally don't actually spread across the, you know, the sutures of the skull.

You have the sutures of the skull. For example, like sagittal suture, or you can have the coronal suture, the squamous suture, the lambdoid suture, all these sutures. What happens is, is right here you can have this biconvex type of structure here.

And this is bad because look what it's doing. It starts pushing down on the brain substance. As you push down on the brain substance, what can that cause?

You know, whenever you push down on the brain, you're gonna try to herniate the brain and that could be a very very bad thing because her brain herniation can basically very very quickly lead to coma or Possibly death so then what you're gonna see here when you take them To a CT you'll see it. You'll do a CT of their actual skull or your head CT and you'll see this Biconvex or lens shaped type of hematoma. All right, that's what you'll see here.

So We'll talk about, we'll write that down afterwards, but this is what I want you guys to see. You're going to see this biconvex or lens-shaped hematoma. Now, next question you should ask, what symptoms are they going to be showing?

Well, generally, when someone has this type of hematoma formation, most commonly because of the intracranial pressure, they're going to show signs of a headache. They're going to show signs of a headache, even some nausea. We're going to put in for nausea, some nausea, some vomiting. And on top of that, they might even have focal neural symptoms. What does that mean?

Depending upon the area that this mass is accumulating in, it can compress the brain substance and affect the normal function of that actual cortical tissue. So it can cause focal neural symptoms. What else would you see from these patients?

Well, here's another thing. As these patients start having these masses, it starts trying to push down. on the actual brain substance, right?

There's a specific lobe, your medial temporal lobe, it's called the uncus. As these epidural hematomas accumulate, they push and push and push down on that uncus to the point to where it tries to herniate out through what's called the tentorial notch. Remember what we call the tentorium cerebelli? Look, imagine here I have it going like this.

Here's one part of the tentorium cerebelli, here's the other one, right? And again, what's it doing is it's separating the cerebellum from the actual cerebrum. There's a little hole here called the tentorial notch. And what happens is a part of the actual brain substance can herniate through that area there. And that's what actually happens.

So if someone gets what's called a tentorial herniation, it can actually compress a specific nerve that runs right in that area. You know the third cranial nerve? It runs right through that area.

So sometimes you might even see the person having a third nerve palsy. And if you guys have watched our video on the third cranial nerve, you'll know what those signs are. You know that it actually is going to cause a down and out movement and might even cause pupillary dilatation.

Okay? All right. Now, something else that you're going to want to look at is going to be the diagnosis, right? So whenever you're trying to diagnose the patient here, you're going to try to do a head CT.

So you want to do a head CT. Okay, so you're going to want to do a CT scan of the head. So do a CT of the head. When you do the CT of the head, what do we say it's going to come back with?

This biconvex or lens-shaped hematoma. But what did I tell you? It doesn't cross the sutural ligament line.

So when you do a CT of the head, you're going to see a, we're just going to say a lens-shaped hematoma. And again, what do we say? It doesn't cross suture lines. That's important.

That's going to be one of the defining factors between that and a subdural hematoma because they actually can cross the suture lines. Okay, so now we know if we're looking at this patient, we're going to see these basic signs. Now the next question you should have is how do we manage it?

What do we do? Well, You can actually do what's called a craniotomy or a burr hole and evacuate the mass. You can actually drill right through here and drain the actual blood or the hematoma. So that's one thing you can do, but it depends.

If the intracranial pressure is really high that they're at risk of having a brain herniation, then yeah, you're going to want to evacuate the hematoma. So first thing you're going to want to try to do is evaluate the patient, see if it's necessary to evacuate the hematoma. All right, now...

If they do have, sometimes because of this, when you're going to have to put in this type of hematoma. So next thing, if we evacuate the hematoma, that's usually because of some type of serious issue. That's necessary. Depending upon how large it is, you're increasing the risk of brain herniation. But sometimes we might not have to evacuate the hematoma.

Sometimes we just might have to maintain. in the person's intracranial pressure. And the ways that you can do that, well, first thing, depending upon if there is cerebral edema, you can give them something called mannitol, and you can give it IV.

And what that's going to do is it's going to decrease the cerebral edema in the area. Another thing you can do is you want to elevate their head. So elevating their head can also help in this process. Or even putting shunts in, sometimes putting a shunt into the area and draining it, that's been found to help. But sometimes there can be some minor complications when you're doing that.

And another thing that you can also do besides the mannitol, elevation, or shunt is they find this to be helpful sometimes is hyperventilating the patient. Hyperventilating the patient has been found to be able to stabilize the intracranial pressure. Okay? So now we go into the next one.

The next type of bleed is going to be right after. So epidural space, subdural space. So what do you think this one's called?

This one is going to be called the subdural hematoma. So this next one here is going to be subdural. Subdural hematoma. Subdural hematoma.

Where does it occur? What's the location? Subdural space.

Keep it simple there. Subdural space. Now, the next thing that you should ask yourself, we know it occurs in the subdural space. The subdural space is going to be where again?

It's going to be in between the arachnoid mater and the inner meningeal layer of the dura mater. Now the next thing that you should ask yourself is now the locations they can vary. It can honestly vary from person to person depending upon the type of situations that this occurs. Because subdural hematomas they can be very very severe depending upon if it's an acute or chronic type of hematoma.

Acute is like if someone actually gets up in a motor vehicle accident or if they've had a severe trauma like blunt force trauma to the head or if they are older. Sometimes as people get older. their brain atrophies and it's easier whenever there's very very Sudden shifts within the brain it can actually tear or shear certain types of bridging veins Okay, so subdural hematomas occur in the subdural space and the locations vary Okay, but what's the mechanism what we said could be due to a motor vehicle accident?

I'm gonna put MVA could be due to some type of trauma right and another thing is it could be due to Falls And again, the falls are a little bit more common with the older individuals because as they get older, their brain atrophies, which allows for the brain to move a little bit more inside of the actual spaces. And remember, the cerebral spinal fluid allows for the brain to float. It provides buoyancy. But with very, very sudden movements, acceleration, deceleration, it can shear specific types of veins that run through that space.

What are those veins called? Those veins are called your bridging veins. So they're called your cortical. Bridging veins. So what happens is during these, like pretend you're in a motor vehicle accident.

So you're driving at about 60 miles an hour all of a sudden you hit a truck, right? What happens? Your head moves forward and then it comes back.

Usually this causes a counter coupe type of a reaction and because of that the movement forward and backward stretches those bridging veins and then shears them and that's what becomes so bad. So shearing of the bridging veins is usually in the mechanism by which it causes a subdural hematoma. These are usually the most fatal.

Out of the home hematomas, this is one of the most fatal if it's acute. The person can die very, very quickly if not treated properly. Now, symptoms. These ones, again, it can vary.

It really does. It varies a lot from person to person. But generally, whenever you see someone with some type of intracranial bleed, Usually they're going to have headaches.

Because signs of intracranial pressure is usually headaches, vomiting, their blood pressure changes. Here's a good way to remember, because sometimes people will switch them up. Think about shock.

In patients who have shock, what happens? Their blood pressure drops, their heart rate goes up, their pulse goes up, and their respirations change also. So whenever you're seeing someone in shock, you think about their blood pressure.

Theirs goes what? down. So in a person with intracranial pressure, they're going to have a high BP. Also think about their pulse.

Well, a person who is in shock is going to have what? They have a high pulse. So this person would actually have a low pulse.

And you might even see the person due to this type of situation, they might even have some type of confusion. Okay. They might have some confusion or a loss, not loss of, they can't actually lose consciousness, but it depends upon the severity. That reminds me of something.

With epidural hematomas, what I want you guys to remember for the symptoms here, this is honestly the most important thing to be able to differentiate these two. With epidural hematomas, This is super big. They can lose consciousness. So LOC, they can have loss of consciousness.

But then when they lose consciousness, some of the patients, after they gain or they actually go back, they actually gain consciousness, right? They can act absolutely normal. Their vitals can basically go back to stable levels.

They can be normal. That is called a lucid interval. But then here's the big thing. If these patients exhibit a lucid interval, Most commonly right after that lucid interval the patient starts declining very suddenly and very rapidly and they can even go into a comatose state or depending upon the severity death. So that's one of the big things that I want to definitely make sure you guys understand to differentiate this point here is that epidural hematomas show loss of consciousness with a lucid interval where they basically their vitals go back to normal They're acting like everything is okay, but then all of a sudden they start declining very, very rapidly.

People with subdural hematomas, they generally don't show any signs of any lucid interval. That's an important thing to remember. Okay, so we got the symptoms. We know that it can vary, but generally headaches, blood pressure changes, like increasing, decreasing pulse, confusion. And like anything, because of it, it can even cause some nausea and some vomiting too.

Now how would you diagnose the patient? You send them to CT. Again.

You're going to do a CT scan for pretty much all of these. But send them to do a CT scan. So you do a CT of the head.

When you do a CT of the head, what are you going to see? Okay, well let's come over here. Let's get my red marker here.

So again, what was the space right here? Right here. What you're going to see is you're going to see blood is going to occupy this area here.

And when it does, it occupies this subdural space. The bleed that it, the shape that this bleed makes is usually going to be crescent shaped. or concave in shape. So you see how it kind of forms this concave shape or this crescent shape structure?

That's important because what it can do again with any of these bleeds is it can accumulate here and start pushing down on the brain substance. And as it starts pushing down on the brain substance, this can increase the intracranial pressure. So this is kind of what you would see in this patient like this.

Okay, so when you do a CT of the head, You do a CT and you'll see that the patient will most likely have a crescent or we can say concave hematoma. And what did I tell you guys? The epidural did not cross the suture lines. This one can cross suture lines.

Okay? Now, next thing. We did a CT. We verified that they did have a bleed. They have a subdural hematoma.

The next question we should say is, what the heck do we do? Well, these are bad. The reason why is, let me come back over here for a second. These crescent-shaped bleeds, right, that you see over here, they can start pushing the brain substance. Because they can spread past the suture lines, they can start pushing the brain substance to one side.

And as they start pushing the brain substance to one side, what do you think is going to happen? It's going to shift. the midline of the brain. Imagine I make a vertical asthmatoid right here.

The vertical asthmatoid should be right here, but as this brain substance starts pushing and pushing and pushing, it starts shifting the midline. If the midline shifts greater than, if they have a midline shift greater than five millimeters. So if there is a midline shift greater than five millimeters, we need to evacuate the hematoma.

Okay, so if they have a midline shift greater than 5 millimeters, this is necessary. The protocol would be to evacuate the hematoma. Okay, so that is going to take care of our subdural hematomas.

Now we go to the next one, subarachnoid. Subarachnoid hematomas, these are also very, very, very bad. They're all very bad.

I mean, they all have their own thing, right? Subdural, I'm sorry, subarachnoid hemorrhages. Subarachnoid hemorrhages, where do you think that these bad boys are going to occur?

In the subarachnoid space. So now we're going to have the subarachnoid hematoma. And again, the subarachnoid hematoma, where do you think it's going to be occurring? It's going to be occurring right here within the subarachnoid space.

Okay? So again, where's the subarachnoid space? Remember, it's in between the pia mater and the arachnoid mater.

Okay? Now, we know again, where is it going to occur? In the subarachnoid space. Now, the mechanism. Generally, this is most commonly due to berry aneurysm ruptures.

So most commonly due to berry aneurysms, or they also call them saccular aneurysm ruptures. What the heck is a berry aneurysm? You know, the circle willis, if you guys remember.

You have the circle of willows. We're not going to go through the whole thing, but I just want you guys to remember a basic thing here. Pretend here we have, for a second, we have anterior cerebral arteries, right? And then you have your anterior communicating arteries. We'll get those in a second.

And then you have your middle cerebral arteries. You have your posterior communicating arteries, posterior cerebral arteries, right? And again, feeding these is the internal carotid.

Feeding these is the internal carotid. And then let's just make this special here. We're going to say this is the posterior communicating artery right here, and these are your anterior communicating arteries. What happens is, is for people, they actually can, it can be due to genetic conditions, like Ehlers-Danlos Syndrome or Marfan Syndrome, whatever it might be. The blood vessels, if you guys watch our tunic layers, they have a tunica interna or an intima.

Outside of that, they have another layer, and there's this like elastic tissue. It's called the elastic lamina. You know the internal and external elastic lamina? As people are due to hypertension or due to connective tissue disorders, this tissue, this elastic lamina, can decrease. So as the elastic lamina concentration decreases, what happens as pressure is actually coming out here?

Because the purpose of the elastic lamina is to accommodate stretch but recoil and assume the normal size. But if you're decreasing the concentration of this, whenever it's stretched, it won't be able to return to the normal size. And so what happens is it forms like a little balloon.

And this little balloon that you're going to see here is called an aneurysm, right? So because of the decrease in this elastic lamina tissue, it can cause these bulgings of the actual blood vessel wall. And what happens is as this continues and continues, guess what it can do? It can rupture and blood can start spewing out. Where do you think it spews out?

Right into the subarachnoid space. Now, let's write that down. So, barianeurism, saccular aneurysms are usually, if you wanted to remember the most common areas, it's usually due to the anterior communicating arteries. That's usually the most common. So, the anterior communicating arteries or the middle cerebral artery.

There's also another one. So, the middle cerebral artery, the anterior communicating arteries, those are usually the most common ones that can actually rupture. So, what are some of the symptoms? Now, this person. is going to have a headache like they've never had in their entire life.

So they are going to have, they actually call it like the thunderclap headache. Thunderclap headache. It's going to be excruciating headache.

They say it's the worst headache they've ever had in their entire life. Sometimes it can be unilateral, sometimes not. Sometimes it can even radiate to the occipital region too.

Now another thing that you're going to see with this person is they're going to have some signs of nausea, some vomiting also. But these patients usually don't show any, no focal neurological symptoms, which is good, but they don't show any focal neurological symptoms generally. But what you will see in this patient is they're going to start showing meningeal symptoms. What do I mean? When someone has like meningitis, they show neck stiffness.

And sometimes you can see that when you do like the Koenig's test or the Brzezinski's test and stuff like that. But these people will have a lot of neck stiffness. Another thing is they'll be very sensitive to light.

Photophobia. All right, so they'll have photophobia. And they might start losing it, man.

They might start actually becoming delirious. So another thing that you might see within these patients is they might start showing signs of delirium. So what are you going to see?

Thunderclap headache, nausea, vomiting. It can actually be unilateral or not. It can radiate to the occipital region.

They might have some neck stiffness and photophobia and delirium, which are basically meningeal symptoms. But again, they don't usually show any focal neurological symptoms, which is interesting, right? Now, how would you diagnose it? CT scan. So send them to CT.

That's your first thing, right? Do a CT of the head. Now, when you do the CT of the head, here's what you want to look for.

You want to see a bleed within the subarachnoid space. But here's the important thing. If the CT is positive, okay, here's the important thing.

If the CT is positive for a subarachnoid hemorrhage, Then you send them to do the gold standard, basically, which is a four-vessel angiography, where they go in and they determine where the actual vessel, the aneurysm ruptured. Okay? That's a good way to completely confirm that they had a subarachnoid hemorrhage.

So if you do a CT and you think that you saw a bleed, you send them to do a four-vessel angiography. But here is the key. You don't do the lumbar puncture if you think that they might have it.

Okay? You do that if it's negative. So if the CT is negative, then you do a lumbar puncture.

If you do the lumbar puncture, what are you looking for? Usually you'll have what's called xanthochromia. Xanthochromia.

It's a yellowish pigment. This is usually a sign that the person has red blood cells in their cerebral spinal fluid. Another thing that you want to see is... Check their cerebrospinal fluid pressure, their opening pressure. So you'll check the cerebrospinal fluid pressure, and if it's high, that's also showing signs of maybe high intracranial pressure, okay?

How would you manage this person? This one, there's new techniques that they do now. Well, first off, if it's not as bad, let's say it's not bad. Let's say it's not a really, really bad one. You can give supportive care, okay?

And supportive care, basically for this, you do... You'll do bed rest, you'll do stool softeners. What else would you do? Another thing that they can do for the patient is they can give them medication to lower their blood pressure gradually.

So you want to lower their blood pressure gradually. So you give them a bunch of different types of drugs. You can give them, you know, they give labetalol. Labetalol is an alpha and beta adrenergic blocker.

So you can give them labetalol. There's another drug that you can give which is nicartapine. So you can give nicartapine or you can give another one which is called nemotapine.

And again, I'll just put it here. These are alpha and beta blockers. And these two are calcium channel blockers. And again, the whole purpose of these is just basically to lower the blood pressure gradually.

Now, the next thing I want to tell you guys. So if we do supportive care, if it's not that bad, what if it is really bad? They have these new techniques now that are just unbelievable. So what they do is they actually take, let's pretend we have that aneurysm over here. Again, we come back over here.

They take like a little catheter basically. They feed it up through your femoral vein. And what they do is this catheter, it comes up here to where the aneurysm is.

And they inject out here this surgical coiling like structure. So they do what's called surgical coiling. They used to do clipping where they come in there and they clip that off, but it was just, it was too invasive.

So they found different ways to do this, getting very, very good results without having to have that such of an invasive effect. So what they can do is they go in here and they actually insert this little cat, this actual coil. It's called an endovascular coil.

And the endovascular coil will basically block off the blood flow to the area, which prevents the rupturing of that vessel. Okay, so that's one way that they can do that is they can actually do what's called an endovascular coiling or clipping. So again, over here, if you want to remember, if it's severe, they can do coiling, which is the preferred method nowadays, or clipping, which is the more invasive one, of the aneurysm.

And your is okay. All right. So we got that. Now we have the last and final one. The last and final one that we're going to do here is going to be the intracerebral.

So the last one here is going to be the intracerebral. So intracerebral hemorrhages, there is many types, right? There's actually a bunch of different types and we're going to hit the basis of it.

We're not going to go super super intense. We're going to hit what we need to know this, right? So intracerebral hematomas.

Location. Let's hit the basic locations. So let me go ahead and get this stuff out the way because I actually need this now.

There's a couple different areas. We're going to hit the most common ones. There's so many areas, but we're going to hit the basic ones. If you guys remember, we've talked about it a couple times. You know you have an artery right here.

It's called the middle cerebral artery, right? Well, the middle cerebral artery gives off these branches, okay? It gives off... These branches that come over here and supply this nucleus. You know what this nucleus over here is called?

They call this nucleus the lentiform nucleus. They call it the lentiform nucleus. So these arteries, they're actually going and supplying a lot of these different structures of the lentiform nucleus, the basal ganglia.

What can happen is if people who have, there's a bunch of different causes. But if they have certain types of arteriovenous malformations, they might even have aneurysms here, they might even have amyloidosis. So there's many different causes. Hypertension is another cause here.

These vessels rupture. When they rupture, what is the name of these vessels actually? That's what we should know.

What is the name of these vessels? This is called the lenticulostriate. Artery, arteries. If these are affected, it affects the lintiform nucleus, like the putamen, the globus pallidus, externus and internus.

It can even affect some of the other structures like the caudate nucleus. And this can cause some really, really bad problems. So there's one type of hemorrhage.

Another one is you have these arteries here, these arterial branches. And these arterial branches that are going to the thalamus, these are actually called jaw. geniculate arteries. These are called your thalamogeniculate arteries. If these, due to hypertension, amyloidosis, or some type of arteriovenous malformation, they actually rupture, it can cause a bleed that's affecting the thalamus.

What other structures? Well, remember, we also had, if you guys go back and remember, we have the vertebral arteries here. And the vertebral arteries come together and form what's called the bacillar artery.

And the bacillar artery is giving off these little branches here to the pons, right? They call them the pontine branches or they can even call them the paramedian pontine branches. If these are affected due to hypertension, amyloidosis, arteriovenous malformations, it can affect the pons. What other areas?

You know there's other areas over here too where you can have effects. There's the cerebellum. You know there's a bunch of different arteries that are going to be going to the cerebellum. Remember we had the anterior inferior cerebellar artery and the posterior inferior cerebellar artery.

There's even the other ones like the superior cerebellar artery. If for some reason due to hypertension, arteriovenous malformation, amyloidosis, these rupture, it can cause a bleed within the cerebellum. So what locations are we going to find these suckers in? We can find bleeds within the thalamus.

We can find bleeds within the basal ganglia, we'll just say, like the lintiform nucleus, the globus pallidus, the caudate nucleus. We can find it also within the cerebellum, and we can find it within the pons. Now, what's the mechanism?

Again, we said it's usually due to some type of... Bleed due to hypertension. So hypertension is one common cause here of those blood vessels that we mentioned. Another one is an AVM, an arteriovenous malformation. We talked about this in microcirculation when there's basically a big, the flow of blood in a capillary bed doesn't go through the capillaries.

It goes through a big arterial to venial connection which causes the pressure to build up and it can rupture. Another one is amyloid deposits. as we said, right? So amyloid deposits.

All of these things can basically be the mechanism by which those vessels can rupture. What type of symptoms would you see? Again, basically you're going to see headache, nausea, vomiting. Another thing this person might actually have is you're going to actually see that they can have, depending upon the areas that affected, is they might have hemiparesis. So they might have this loss of sensation.

They might even have the loss of motor tone. which we call hemiplegia, right? They can have these types of symptoms too.

And depending upon how severe the injury is, they might even have a brief loss of consciousness too, okay? How would you diagnose the patient? Again, you're going to do a CT of the head.

So do a CT of the head. See if you can find some type of intraparenchymal bleed via the thalamogeniculate arteries, the lenticular striate, the paramedium pontine. Superior cerebellar, anterior inferior cerebellar, posterior inferior cerebellar arteries.

If you see those, okay. Most likely they have some type of intracerebral bleed. Here's the thing.

Goes back to this thing up here, but with subarachnoid. If you suspect that they might have an intracerebral bleed, do not do lumbar puncture. You could kill the patient. You could cause their brain to herniate because of the high intracranial pressure. So do not do a lumbar puncture if you suspect that the person might have an intracerebral hematoma.

This is a no-go. If you think that they might have it based upon looking at the CT scan, how would you manage it? Well, again, if it's the problem with the intracranial pressure, if they have high intracranial pressure, give them the mannitol.

The mannitol is going to help to decrease some of that cerebral edema, decreasing that actual intracranial pressure. Another thing that you can do is depending upon sometimes because of these structures here because of These arteries if they actually start causing Compression here or compression here or compression on some of the nuclei here Compression on some of the cerebellar structures here it can start causing a lot of problems and they call that when it's starting Compressing the brain substance. It's called mass effect if you see If mass effect is evident, evacuate the hematoma. Okay?

Now that intracranial pressure is a bugger, man. And here's another thing. One last thing that I want to say before we finish up is when you do the subarachnoid hemorrhages, one other thing that you can do is when you do ophthalmoscopy, you look into the actual retina, if you see that the patient has retinal hemorrhaging, This is called Turson's Syndrome.

So look to see. Another thing about the subarachnoid hemorrhage is if you see that the person might have retinal hemorrhaging, that might be another telltale sign for a subarachnoid hematoma. All right, Ninjas and Nerds, so that pretty much tells you guys everything that you would need to know about these intracranial hemorrhages. I really hope it made sense.

I truly do. That is our true, true desire to make this stuff make sense for you guys. If it did, please, I'm begging you, hit that like button, comment down in the comment section, and please subscribe.

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Transcript for:Brain Meninges | Epidural, Subdural, Subarachnoid, & Intracerebral Hematomas

Transcript for:
Brain Meninges | Epidural, Subdural, Subarachnoid, & Intracerebral Hematomas