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So hopefully that's moving. Um If not, let me know in the chart, this was uh the list of disorders that uh the University of Leicester Medical students are required to know. Um So I have picked out perfect some of the er er common conditions and things. I think you definitely have to know when you are an F one on the ward or an ED. And the aims today are just talk about um why we request imaging. Um a brief overview of the different modalities that we can use to image the er brain central nervous system, revise um basic anatomy, um imaging anatomy of the brain um and have a look at some common pathologies and practice interpreting some scans. OK. So generally speaking, we image to make a diagnosis, some of these will be obvious from the clinical history. So as you can see this reconstructed 3d image of a patient's head and there is this very linear structure protruding from the outside of the skull all the way in through the head. All the patients that I've collected images from have been imaged in Lester and this patient had a nail fired in from a nail gun into his head. Fortunately, he survived, not without some deficits, but uh CT imaging is one of the ways we can image uh our patients. It's also used to inform treatment. So uh in the top right, you can see the CT and there are these dots around this patient and this is for radiotherapy clinic also for follow up of scan patients, post treatment. So you see if they responded to chemotherapy radiotherapy and look at different factors which have resulted from treatments such as treatment complications, whether the disease has progressed or is responding to treatments. Sometimes um clinical colleagues, particularly on um I ask for our help um to determine whether the what the prognosis of our patient is likely to be. Um and also for research. So how do we image? Um so we can depending on the age of the patient, uh different mentalities can be used. Um This image here at the top left um is an ultrasound scan which can be uh uses uh high frequency sound waves to have a look at the brain. But this is only possible when we have what we call a window. Um uh an acoustic window which uh allows the sound waves to pass through. Um Typically, this is the anterior fontanel before the skull fuses um x-rays. So we can see facial bone and uh x rays here and uh sonogram here. So facial bone x-rays typically used to determine if there's a fracture. Uh This is a sonogram which means we are still using x-rays. Um but we have injected dyes into the uh into the uh carotid duct here. But it's also possible to inject um uh iodine based dyes into the um uh spinal canal to perform ct myelograms and look at the uh nerves and spinal cord in patients who have contraindications to other modalities such as MRI if they've got a pacemaker on the bottom left. This is a pet scan, which is a type of nuclear medicine scan that we use to investigate for Parkinson's disease. And in the center here is um a pet scan which is another nuclear medicine type test um which uh has, it isn't used to um at some centers to assess for various dementias and and other malignancies elsewhere. However, the majority of the time uh the work courses are CT and MRI and CT is readily accessible 24 7. It's very quick. Um It gives us an answer quickly as to what's going on inside the patient's head. Whereas MRI gives us a greater tissue resolution um brain, um it takes quite a bit longer to scan a patient. Um And as I touched upon before, um isn't necessarily possible in all patients, particularly if they have something like a um a non Mr compatible pacemaker or other implanted devices. So throughout the talk, I'll be using both modalities to talk you through the normal anatomy. Um But first of all, we have to make sure that we are able to orientate ourselves on the scan. And by this, I mean, describing what uh plane we're using um and what's anterior, what's posterior and our left and right. So uh common to all, almost all other body parts and how we image and the left and right is reversed to get back to that. So on the right hand side of the screen will be the left hand side of the patient. And on the left hand side of the screen will be the right side of the patient. The anterior posterior are usually uh fairly obvious because the eyes will typically be out the back. Um and you'll be able to see the ears on the sides of the head as well. Um Coronal image, so slicing somebody from top to bottom, superior and inferior are going to be obvious. And again, the left and right uh sides of the patient are not altered. Um And they are consistent between the axial and current images. Finally, the Sasha, which I think is the most uh common sense and intuitive in inferior. Again, the same and anterior, you can see the frontal sinuses and part of the orbit here and this is the back of the head with some of the c spine muscles good. So, quick review of the anatomy uh on imaging, these are all selected um brain windows. So you can see the skull is a thick white line around the periphery and then surrounding that there's a slightly darker line which is the subcutaneous fat in the, the skin, which you can just about see highlighted here. And within that, you'll have uh the cerebral hemispheres and, and depending on what level, what axial level you've taken, you'll see that the frontal lobes may occupy a very large, small and even small amount. And the different lobes appear as you come uh from superior to inferior uh inferiorly, the midbrain appears as the first part of the brainstem. And then the pons and I haven't taken a slice of the medulla as it then joins onto the cervical cord. And posteriorly, it can be sometimes difficult to appreciate where the occipital lobes are particularly as the cerebellum. Cerebellum will start poking through between the two leaflets. Comes to that in a couple of slides time. This is again to show you the different lobes on the three planes you can see depending on where you slice it. Um which part of the brain where yeah, it will be easy to push uh stacked on top of each other. And then the medulla will appear here uh joining onto the so called the CHD and right on key, we've got uh cerebellum. So the tentorial leaflets here with the cerebellum below and two cere cerebral hemispheres above. So anything above the tenor means supratentorial, anything below is infratentorial and that's why good. This is a a focused um narrowed MRI image of the front of somebody's head and just trying to show you what the different spaces are and what the uh signal, what the areas are. So again, skin to skull. And then you have got subarachnoid space which was previously on the CT and quite dark. But on this selected T two sequence will be right. And then underneath that will be the brain with the crema peripherally which was bright on the CT and then it was slightly darker on the CT. But uh a dark one look this T two sequences, the white matter underneath the two cerebral hemispheres are separated by the uh F cerebra. So that occupies the interhemispheric fissure which goes on to talk about the various CSF spaces. So again, we've got two lateral ventricles which join together and they have a foramen of one row each side to join to the third ventricle. And us. Uh Luckly, we've got the two Sylvian fishes uh which is where the middle artery comes out more inferiorly. We've got the basal system. So this is a prepontine system because it's in front of the pons. But we've also got between the brainstem and the cerebellum, the fourth ventricle on the sagittal image. And this is at one image, you can see the flat bright but the CSF is now suppressed and dark. Um Let's go back. Um We've got the nose here, we can see the upper lip and also the tongue. This is, these are the uh ethmoid air cells in the sphenoid sinus just above the sphenoid sinus is the cusa which holds the pituitary gland. And with the I A, there's a, a pituitary stalk there as well above the pituitary gland we all know is the optic which is this line here. Um And again, you can see a corpus callosum which is this with the brain stem. So the brain, the dull and that eventually will carry on down to the spinal cord and posterior to this is the cerebellum. And that's the fourth, that triangle, there is the fourth ventricle which is joined onto the third by the cerebral aqueduct, which isn't shown on this slice. Is everybody keeping up. Did anybody want me to go over any of the splicer or do the slides? Ok. Ok. I'm gonna take that as we're happy to continue. So, here is the first slide and let's see if it works how. Ok. So hopefully you can see the furthest pole one good. Um Here, I've got a uh single selected axial ct for you. And whilst you're reading the history, I'll just talk through some of the anatomy. Again, these dark slits are the two ventricles and just about see the third ventricle there, a fissure on the right. Uh We've got deep gray matter structures and peripherally that's the bright gray gray matter with darker white matter on the CT. You can see some of the dark CSS spaces, the cell side um and on the CT the skull is completely white and, and it's quite difficult to appreciate if there is anything, any abnormalities on it because it's so un and so bright. Two. Mhm. Yes, good. So that's the majority of people. Ok. So the answer in this case is, so the question was which vessel is the most likely occluded? And so the abnormality before I go on is this uh area of hypodensity? So it's darker than everything else. So it's less dense. That's what we call this hypo density. Um It's not, I say it, I call it a a wedge shape. And you can see there's, you can't differentiate between the gray and the white matter and that's the or fissure which should be running around here, we can't appreciate at all. So this is the left side of the patient and the vessel that typically supplies this area usually supplies. This area is the left middle cerebral artery. OK. So everybody who chose left middle, give yourself a pat on the back. And this is a slide and these are all images taken from the same patient. Um And this is what this is the to demonstrate the progression of stroke um over time, um A they actually presented on the 21st of January and the very early earliest findings are even things called what a hyperdense vessel, which is when the there's, there's a clot or thrombus in the vessel. And we can see there's something called bright, bright white we can't see on this case. And the next thing is um the area that blood vessel supplies, you lose that gray white mass differentiation. Um And so you typically you see a bright white ribbon, that's the insular cortex here where my mouse is hopefully projecting open hair, so becomes smudged, loss of definition. And over time if we don't open up that vessel, and we see the image that we showed you before that all of the area that's supplied by the vessel, uh distal to the occlusion er becomes ischemic and infarcted. And so that swell the cells swell up and the CSS spaces become flattened or squashed what we call effaced and then over time. So this is in uh may, may of this year, no, not may of last year. Um That area uh ties off and shrinks and we get it becomes even darker and more along the lines of the CSS spaces. So it becomes similar density. Um And if you look at the lateral ventricle occipital film here and compare it over time, that's slightly bigger on the left posterior, on the left lateral ventricle. And whereas it was sort of equal in size from both previous images, that's because uh as the discovers a fixed space, things take up the room that has been lost by the brain that's been lost there. OK. And so the ways to differentiate an acute infarct would be that the CSS spaces are squashed or are faced. Um Maybe some of the ventricular ventricular system may be your face as well. And if it's more chronic, then it will be a similar density as the CSS spaces and you'll get what we call a dilation or X factor dilation of the ventricles. So they become slightly bigger out, try that best. Um This is a companion case. So um a 42 year old female presented with severe dysphasia and right sided limb weakness. Um And what we do now is we uh perform a non contrast ct to see if there's any hemorrhage. And if they're within the time window for intravenous thrombolysis, they can receive intravenous thrombolysis. But they also get if the uh team thinks that they would be a candidate for treatment, um A CT angiogram. So this patient has had contrast injected into the uh a venous system and we have time to scan so that the arteries are uh optimally opacified. So they are as bright as we can possibly get. And here we have the internal carotid artery comes up here and branches off into the anterior cerebral arteries towards the front of the head and also out towards the uh left and right. This is the right artery. You can see it goes all the way into that silver fission like I was explaining before. But on the left, there's an abrupt cut off and there's a fewer vessels here than there are on the other side. And so what we've got is an occlusion, a clot there um within a vessel that we potentially retrieve. And here in our patients go over to Queen's Medical Center for Mechanical thrombectomy. So, Mt and this is before the before images, I was taking images from the side. This is coming up the internal to see there's occlusion there. I know afterwards, remove removal of the clot, you can see much better opacification of all those vessels that were supplied by that. Uh middle artery. It's quite dramatic, isn't it? And what just uh this is an ap view. I can just about make out the uh sockets of the orbit here up the internal carotid artery, not very many vessels. And after it opens it up, you can see it draining out quite efficiently into the venous sinuses as well. So this is great because the uh multiple randomized controlled trials in the 2010, mid 2010 to 2015, 2016 in New England Journal of Medicine, um demonstrated the uh excellent functional outcomes. Um after mechanical thrombectomy on large vessel occlusions in the anterior circulation, and this patient um benefited from it immediately. Um Having seen this first hand myself, patients come in with um occlusion, uh severe neurological impairment and practically on the table, I saw them do this on awake patients, they're able to uh uh move sort of the digits to find ways to movements and speak without um any deficits as well. So, no dysphasia or aphasia. And two months later, this patient was followed up at a good level of speech and excellent physical function, which is a really good outcome for this patient. Um um considering how young she was the likely disabilities, the social care that will be required if she had that deficit before, it's really impressive. So if you wanted to look up what some of the nice guidelines were, this is the link. Um and it can be done, typically, it should be done within six hours, but we have evidence um between 12 and 24 hours that there there is brain that can be um uh rescued or salvaged. Um Then depending on what, whether it's available at your center and uh and whether the patient is a good candidate, then that's what should happen good. Um These two images are just to show you what an anterior cerebral artery and a posterior cerebral artery infarct would look like as well. So the anti cebral arteries are much more closer to the midline. Um Again, the the actual loss of brain or mass differentiation will be exactly the same. It's just the distribution will be different. And again, the posterior cerebral will be lower back involving uh medial, posterior, medial temporal and the occipital lobes. You can see just how the variation I guess are dependent on where the vessel was occluded um and also intravariation uh of the of our patients because the branch is supplying different aspects and may come from either the different vessels themselves. Ok. So case three and start with, hopefully you guys can see po so uh this is a 57 year old female and, and they were found to collapse cardiac arrest. So uh ed colleagues requested a CT to see what was going on. Um What do we think? Thank you. OK. Yeah, it looks like people are a bit more hesitant with this than they were with the previous one. So I will talk you through it. Um Again, we've got an axial CT image and it's in the brain window. So we can't see much of this. Uh OK. Differentiation of the skull is just a bright white. Um But unlike the previous patient, um we can't see any differentiation between the gray and white matter at all. Um with a 57 year old female, 57 year old patient, regardless of gender, the CSS spaces should be slightly bit slightly more prominent than they are here. Um And certainly I'd be expecting to see the lateral ventricles more prominently. Um And all those factors combined with the history are most suggestive of hypoxic ischemic brain, which essentially you can use to think as a a generalized uh sort of cutting off of the supply to the entire brain, you can't differentiate any of the deep uh gray matter structures. You can't differentiate the gray matter in any of the labs. Um Sometimes uh to the unwary um because the CSS uh spaces, so the c side or on the face, the vessels in between are either clotted uh in the cle spaces um or have a artifactual like a relative hyperdensity. So it can appear as if there is um subarachnoid hemorrhage along the falx or, you know, in the fu um But that's, that's actually the, the abnormality isn't in the fissures themselves is the brain. That's all uniformly hypodensity. OK. S OK. Um And this is the patient a day later. And as you can see these structures, the chordate head, the nucleus also poster in the occipital lobes become much darker and this is inferior to the. So the lateral ventricles are now completely effaced. Um And this is just progression of the in the infarct and the ischemia. So the prognosis for this patient is extremely important. They are unlikely to recover from this. All right. Yes. OK. Mhm Right. So case number four, what we've got here is another actual image. Um And we've got asymmetry. So there's a difference between the left and the right. OK. We've got a slice which is slightly lower than the previous images. So we can see brain stem here. It probably going to be a junction of the brain and pons and, and we've got the cerebellar hemispheres here. We can see the fourth ventricle, you still see some silan fissure here, but there's abnormalities um at the wall and in the interhemispheric fissure. And so the abnormality, the asymmetry is most marked on the right hand side. And so you can see what we call hyperdensity increased density. This is a non contrast CT um but it's not homogeneous. There's a small, relatively small and relatively hyper dense competitive surroundings in the middle. Sure. So what's the most likely diagnosis? It's a 75 year old female who is presented with a clinically a right anterior circulation stroke. So you think this is an extradural subarachnoid subdural or temporary? So we can slightly estimate just go through the image now. So uh this is a subarachnoid hemorrhage. Um And this is why it outlines the subarachnoid space. As you can see it uh causing around the circle into the bend where the silver or is. I can see why uh potentially you might think that this is a temporary hemorrhage. But if you compare it to the other side, there's a CSS space here. That's why I don't think that's the most appropriate answer and what we do. So if we see this, uh uh the patient can go onwards for um coiling of the aneurysm. But uh interventional neuro radiology colleagues would like the vessels to be better delineated to see where, where they're going to go and put coils in first. So what happens is we typically perform a CT angiogram. So again, in the arterial optimizing ification of the intracranial arteries and and there's this bleb here, this rounded uh a a classifying structure arising from the right middle cerebral artery. And that corresponds, I think to that area which is slightly hyperdense on the on the non contrast CT and that's where the hemorrhage is emanating from and it's spread and that's why it's predominantly the hemorrhages on the right and spreading out. Again. There are nice guidelines for this. Um Depending on uh what, what is when the patient presents, um what we find on your CT and just pay attention to what happens uh with a negative CT scan and, and how many hours after the symptoms were presented. So if it's negative and less, less than a week, equal to six hours of symptom onset, then we can think about other diagnoses and we don't routinely need some approaches. But if it's um at least 12 hours, then there's a separate pathway for that. You too. Case number four different patient, elderly female and clinically avoid anterior strike. Yes, sir. What's happened to you? So again, there's uh we're at the levels of the, of the orbit. So you can see both globes here. Uh there is again, asymmetry. So there's hyperdense hyperattenuating increased density material on the on the left hand side of the patient. So in the left brain, some in the middle as well uh but none on the right hand side. So, do you think this is an extra journal? Do you think this has arisen from hypertension? Do you think this is subarachnoid hemorrhage or do you think this is a subdural hemorrhage? Thank you. Got a few last minute boats there. It's quite close. So the current lesion is a high potential hemorrhage but there are some, some votes for the others as well. Ok. So this is a hypertensive hemorrhage. So what's happened is that the origin of it is here in the left uh cerebral hemisphere. Um and it's typically uh hypertensive hemorrhages are typically more central. So they can, they can occur in the thalamus which is where this is arisen from or in the basal pancreas and the Ln it had and centrally within the island as well. But what's happened is that it spread and these uh it's extended into the ventricles. So there's blood in the third ventricle but also it's trapped into the oxygen wall of the left lateral ventricle. And you can see there's a slight curve as the the there's mild mass effectors, mild midline shift to the right from that blood in the left thalamus. So this is a typical image of a hypertensive hemorrhage. They don't all necessarily extend into the ventricles but um a significant proportion do. And this is a quick uh summary slide of the various hemorrhages. So, again, a different case of a hypertensive hemorrhage without extension into the uh ventricular system. Again, this one is centered on the thalamus which just a part the the posterior uh lateral ventricles. And you can see compared to the other side, this one's slightly squashed or faced compared to the left lateral ventricle, an extra dural typically, um the patient population is typically younger post trauma um and has what we call a lentiform shape. Um I've seen it described as like ple um but it's got a, a convex um uh margin by on both sides of the hemorrhage. And they're typically due to ruptures of the middle meningeal artery um but not exclusive. Uh whereas a subdural which is the third image uh has been, I think I've heard described as more like a banana and it follows the contour of the skull. And this one you can see is quite large and it's spreading along the tentorial leaflet. So there's still some asymmetry and hyper density, increased density. There's blood all along there, which is why it's thicker. But this one's so big that it's pushed this left ventricle over to the right hand side. So there's midline shift as well as probably some hydrocephalus from this subject. And this, this will need discussion with the neurosurgeons of hemorrhages are usually managed by our uh strict colleagues and requires BP management. OK. Case number six. Let's stop this. Yeah. Yes, you don't. I can certainly uh not a PDF of this. I'll send it to, to write up and they can it this uh question you don't even need the image. But it is a, a nice demonstration of the optic pathway. So 82 year old male, quite elderly, I guess for, for the population, but they have got a bioral field. So whereabouts in the visual pathway? Uh do you think is the single most likely site of pathology? Yeah. Mhm So this is at one and this is a sagittal image of the patient's brain. We're focused in on the pituitary fossa here. Uh What we've got is the nose. Uh This is the hard palate and tongue underneath and this is the nasopharynx. So nose coming down nasopharynx, the rest of the pharynx will be coming down here. We can see the cerebellum. So, posterior fossa, we can see the midbrain pons, mid CV spinal cord. So that's tectal plate. So this is uh third ventricle coming into the aqueduct and into the fourth ventricle and down. And what we've got is extra material, extra material in the midline. This doesn't look like the image I showed you earlier of a nice normal pituitary gland in the pituitary fossa. And this is the clivus, this is the sella pituitary fossa. Um There's extra material here because what this patient has and the abnormality and most likely cause for the bitemporal field loss is, is a macro pituitary macroadenoma. And so this will push up onto the optic chiasm. And as the fibers split off from both eyes. They develop a bitemporal visual field defect. Ok. So nice to meet 27 7. Ok. Yeah, hopefully you can see that Paul, we've got a 66 year old female who has come to the TIA a clinic and what they actually come wasn't that they've got a, a neurological deficit, but they've got intermittent short term memory problems that they've noticed and family members have noticed. And so what's the most likely a amounting whilst you're having a think I'll talk you through this image. Um This is at two image and you can tell because the CSF is bright, the fat underneath the skin is bright, but also the white matter is darker than the, the gray matter that's reversed on at one. Um There is an abnormality citri um And you can see some whiteness here which represents some edema in the frontal lobes. You can see quite nicely the, the midbrain. So it's supposed to look like a mickey mouse ears in the face. That'll be the f uh coming down to the CSS spaces and this the cerebellar hemispheres and firm, these dark lines should start to um become familiar with from the previous CT S or the middle cerebra arteries coming out. OK. So we've got a structure here right in the middle, in the midline. And so the question is, what do we think this is and why do we think it is that it is a fairly evenly split between, uh, option A and slightly less favored option D seven. Nobody thinks it's a lymphoma which is good. It's not lymphoma. This is a meningioma. It's a very common brain tumor. They're fairly indolent. Um, the main risk. Well, all of the, all of those are reasonable differentials to make, um, the reason why it's a meningioma as opposed to the others is that, uh, it's, you can see the CSF around it. So it's not arising from the brain itself. Uh You could argue that um you could get a singular metastasis. Um But this would be, I guess an unusual place for a single metastasis to arise from, it typically arise within the brain itself. Um The there's the bright stuff here within the brain is edema because of disruption of the blood brain barrier. Um And these arise differently from the facts or these can arise in this case from what we call the sphenoid ali. So when we gave this patient contrast, so you can see contrast in the uh nasal mucosa um and in the vessel. So superior seal, sinus, transverse veins, straight, sinus, et cetera. You can see it enhances fairly homogenously with contrast and it's got um what we call a dural tail extending down towards the actual pituitary fossa. Um which is why these features make it more likely to be in as opposed to a metastasis. Uh You can get a lymphoma, um cns lymphoma it's not the top cause and it can have some um and G BMS typically are, are, are within the brain and particularly more hetero. So uh not uniform like this is good. And so I have one. Yeah, turn up to a case, what have we got here. So we've gone back to a CT uh this patient has had contrast. So you can tell uh by when you scroll through uh if the, the vessels are pacified, um the you can make out the arteries but they're not as bright as they are in the angiogram. And so it's not a dedicated, what we call a dedicated phase to look at the vessels. Um And what we're looking for is asymmetry between left and right. Uh And you can see here that there's very structures that long, slightly denser. So they are hyper dense. But what what's actually happening here is they are uh opacify with contrast, they are enhancing. So most appropriately, they'll be called enhancing intracranial lesions. And this one's got the rim of edema like we saw with the meningioma, but on because it's c it's dark around it. Um And it's pushing up onto the ventricles, elect ventricle and also the third ventricle. And right question is what do you think this is most likely to be? OK. So I pointed out one lesion that's enhancing, but there's another lesion up here on the front, they're different sizes and in different uh mascular territories And so the most likely out of the options here, most likely it is going to be a a metastasis. When you've got multiple lesions, then uh a metastasis should be the top of differential. Um CRE Vasto can have sort of like an infiltrative um appearance, but these are in different cerebral hemispheres. So you'd expect if it was to be bilateral, then it could be potentially multifocal but it is most likely to be from a different primary. OK. So this is a high, OK. Here is a sagittal flare. So again, the white matter is darker than the gray matter. So it's at two weighted image. It's different from the TT two because the the fluid is being suppressed. And so the CSS spaces are dark but it's still at two weighted image. Um and we are just off midline. We can't see the pituitary fossa, we can see it temporal lobe and it's a sagittal image. As you can see these are the teeth, the cerebellum except like cross like frontal my pain. That's the natural ventricle and we've got all these abnormalities rising. Yeah, uh appendicular to natural ventricles. So in a patient who has presented with ataxia weakness, dizziness was the most likely cause. Mhm How much is? So these lesions, these are, these are, these are the abnormalities here, all these brighter appendicular and they are but in the lateral ventricle, these should be there in a in a normal patient. Um these are what are called Dawson's fingers, you can see them coming up here. Um And they are, they always passing the one for multiple sclerosis and it's certainly very common. Um They would need to fulfill mcdonald's criteria. So dissemination in space and time. Um And so sort of a careful history and examination of the rest of the, the central nervous system. So, imaging of the uh whole whole cord with or without contrast would assist in making that diagnosis and that's it. Um Thank you for listening. Hopefully, you found that useful. Uh We've gone through some of the common pathologies. Mind is the basic imaging anatomy of the brain and, and practice interpreting some studies. Um That's all I have. I'm happy to take any questions in the chart and I will put out a, I'll send I'm sorry, copy on the slides for you. Thank you, Doctor Lamb. That was a really, really useful and informative session. Um Thank you everyone for joining today. If you do have any questions for Doctor Lamb, please put them in the chat. I'll send out a feedback form as well. So if you can fill that out, that would be great. Um And doctor Lam, if you're happy to share the slides or share the recording for today, that would be brilliant so that people can refer to them for their revision later on. Yeah. Yeah. Thank you. So, I've just popped the feedback form in the chat. Thanks for attending everyone.