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Can you hear me? Yeah, yeah, I can hear you. Eyesight. Oh yeah, just waiting for MRI to join, right. Just gonna sh I'm gonna try to show my slides. Um Let me know what, hi. Can you hear me? I'm, I'm here. Uh Yeah, we can hear you, Marriam. OK. Just to, just to introduce quickly before um you guys start. So I'm sad. One of the members here at the British Radiology Journal Club um and this is our December meeting talking about neuroradiology. So we have two presenters here, Hussam and MRI who are gonna present their two papers. So um just if everyone can um you would have seen before the screen in terms of um following us on our social media platforms. We've got an Instagram page, a Facebook page and we regularly um post our newsletters after our events and before the event. So our website is, is constantly updated as well. So we would really appreciate it if you guys could um follow us on all fronts and then keep it will keep you updated with uh what we're doing. Um And without further ado um Hasan, would you like to go first. Uh Yeah, sure. That's fine if you can, are you able to share your presentation? Yeah. Um Can you see that? Yeah, I can see it if anyone is struggling or having any issues, please do message in the chat and we'll try and um help you guys. But um, there you go some you can take over. Oh, perfect. Thank you very much. So. Yeah, hi. Um, hi, everyone. I'm I, I'm uh an F two doctor um in Leicester. Uh And uh today I'm just going to be presenting a, a uh research paper or a, a review paper. Um basically looking at the imaging in acute ischemic stroke um just having a deeper dive in the uh the the IMA the imaging that we use. Um And uh what, what the future developments are looking like uh in this field. Um So uh I'm just gonna start with the definition um of what a stroke is. So, obviously, I think most people know about stroke. It is basically a sudden interruption um in, in the, in the blood flow uh to the brain uh which obviously reduces the tissue perfusion um and leads to um brain damage or brain tissue damage, I should say. Um And there are the two main causes um ischemic um which accounts for 85% of um all strokes uh in the UK and uh hemorrhagic which accounts for the, the other 15% and obviously within ischemic, you have um different causes of ischemic um strokes but um ma uh the the the main two ones are are either aros sclerosis which usually affects um the carotid arteries, for example, or a a thromboembolism which can affect the the the main cerebral arteries. Um and obviously, stroke is is one of the leading causes of of mm not only mortality but morbidity. Um and uh and disability in the UK um 34,000 deaths annually. Um and a, a lot, a lot of patients who who have strokes obviously lead go go on to have permanent permanent disabilities or, or temporary disabilities. So moving on, um just want to give you an overview of the management of, of, of stroke. So mainly, mainly looking i in the into the ischemic management. Um It depends on um how, how soon patients are presented uh after symptoms based after their symptoms have started. So if they've managed to present within um 4.5 hours of their symptoms, um and they do and, and they do have an ischemic stroke, then the first line treatment for all patients um would be uh IV thrombolysis usually with um out of places but um uh other drugs uh can be used but um usually a a tissue plasma Imogen activator um to, to basically dissolve the clot. Um after after 4.5 hours, if your symptoms have have been uh going on for more than that. Um We usually uh do a dual anti, dual anti therapy would be the main um treatment. Um And uh these patients wouldn't be considered for IV thrombolysis. Um but fo for so for some patients, um mechanical thrombectomy is a, is a, uh is an option usually before six hours. And um there has to be AAA clear um uh clear source of, of, of a thrombus on, on which um the intervention on your neuroradiologist can um act upon. Um but in some occasions like bacilla strokes, for example, um uh you can, you can do mechanical thrombectomy to up to up to 24 hours after symptoms. Um uh start. Uh but obviously, imaging is essential for, for, for, for mechanical thrombectomy. And obviously, with hemorrhagic strokes, it's more of a neurologic. You, you do have neurological um uh interventions that that can be, that can be done. But uh we won't be looking into that too much um in this, in this presentation. So the first uh the first mode of imaging that I want to discuss is um the noncontrast CT, which is basically a mainstay um in, in uh the management of stroke. So for all all suspected strokes, uh patients will have a noncontrast CT and, and the main main aim of, of the noncontrast CT is to exclude um a hemorrhage. Um Because if uh obviously, if it, if it is an ischemic stroke, then the management is completely different. Um and obviously you wouldn't want to give uh thrombolysis or, or aspirin or forbid grow in a patient with a hemorrhage. And uh it's also important to, to remember that uh stroke is a clinical diagnosis. So even if the, the con uh even if the CT doesn't have any findings, uh that doesn't mean that we're not treat that we're not treating the stroke. So, um it is, its main aim is to exclude hemorrhage, but it can also um show show um some tissue damage. And uh it basically show us where, where the location of the stroke is. Uh in some cases, obviously, the pros of um non contrast CT are very fast um and cheap or cheaper than MRI S at least. So, um that is one of the, the, the the, the pros doesn't need contrast. So you don't have to worry about kidney function and all these things. Um and obviously differentiates between ischemic and hemorrhagic stroke and the, the cons are it is is quite poor in terms of sensitivity, especially if patients are presented early on. Um But obviously, like I said, it is ac strokes are clinical diagnosis. So you will um you will treat these patients regardless. Um uh So just moving on to what I uh this is, so this is an example of a uh an uh ischemic stroke. II don't know if you can see my um my arrow, but basically, if you look at the um top bit, top uh left bit from what we're looking at or the right, right side of the patient. So the right hemisphere uh you can see it uh like a uh hypodensity there which um indicates an an ischemic stroke. And you can also see the, the loss of sulci um which is also um uh indic indicative of, of, of an ischemic stroke in this patient. Um So, moving on um to an a, a scoring um a scoring system that we use, that we use for with noncontrast CT S called the uh aspect score, which essentially um is used for um middle cerebral infarct, middle cerebral artery infarcts. Um but can also be used for uh posterior cerebral infarcts where it's just a, a little bit different. So essentially what, what this does is um it looks at uh all the main area, all the main areas of the brain that are supplied by the middle cerebral artery and sees which one which areas are damaged. So people would you? So for AAA normal, healthy um individual, uh their aspect score would be 10 cause they would have no no tissue damage. But the more areas that are involved you get 11 point subtracted. Um So essentially the lower the score, the worse off the score is and uh any score less than seven indicates uh poor prognosis, uh which is quite important for essentially escalation plans uh treatment moving forward um for that, that sort of thing. So, it's, it's quite a useful tool to, for, for, for sure physicians um and medical professionals generally to um to, to basically uh guide them for during further treatment. Um Yeah, and, and like I said that there is an adjusted scoring system for um for serious. Uh So, yeah, this is, this is basically um all the, I'm, I'm not gonna list out all of the, the areas where, which the middle cerebral artery supplies. But um this is essentially what um it, what, what we're looking at here is uh the, the different areas of the m uh that, that are supplied by the MCA. Um And if there is um tissue damage to any of these areas, you will subtract one from a score of 10 so up to zero. OK. Um And then the next uh the next imaging uh modality that I'll be discussing is CT angiography. Um So C TDR gray is, is essential for, for, for mechanical thrombectomy because it basically l looks at where, where a potential blood clot is within the brain and in which artery it is. Um So for, for, for all patients that are that you, that you would be considering mechanical thrombectomy for they'd need a CT angiograph. Um The pros of it is, is it's very, very good at obviously identifying where the occlusion is where non noncontrast ct, you wouldn't be able to really accurately identify where, where, where a blood clot is. You'd only be able to identify where the damage is if at best. Um And obviously, it looks at the the collateral blood flow. Um and, and where, where the, where there's severe ischemia or, or even infarct. Um the cons are ii it, it, it's not great at identifying small vessel occlusions. Um And obviously, it requires contrast administration. So for patients with um renal failure, I it, it might be difficult to uh it's just something to be, to be aware of basically. Um So this is an example of a uh CT angiogram. Um And obviously, you can, you can see the, the, the, the occlusion um quite, quite uh quite obviously there and and the the subsequent lack of blood flow uh in the right right hemisphere there. Um And this is, this is uh this is an essential um scan for, for, for, for neurointervention interventional radiologists uh when considering mechanical thrombectomy. And the third um CT scan um that uh can be used as act perfusion. Um So, the the main aim of a CT perfusion is obviously to it, well, not obviously, but is to, to basically differentiate from the salvageable ischemic tissue, which is called the penumbra, which is basically tissue that's that has reduced, that has been damaged, but can still be saved essentially. Um And the infarct core, which is the unsalvageable uh brain tissue, which is uh it co it is completely infarcted, basically not ischemic. Um And uh it it is, it's differentiated by, by three things, the mean transit time, uh cerebral blood flow and cerebral blood volume. Uh So it, it, it, it's, it's a bit of a complicated um uh a CT scan to, to, to uh report on but um essentially to differentiate the three with the number you have an increased MTT um and a moderately reduced uh cerebral blood flow and a normal or increased cerebral blood volume. Whereas with the infarct core, you would have an increased MTT but the the cerebral blood flow will be much less and the cerebral vo uh blood volume will also be much less. So that that's the way they identify it. Um And uh this is basically an example um of, of a core infarct. Uh Yeah, so you, you have an increase there. Um ii appreciate it's, it's difficult to, to interpret if you, you if um you don't have much experience with it. But that's basically the um the, the overview of, of, of, of how um we differentiate uh the corn part from the uh penumbra. Uh And then lastly, um moving on to the MRI scans. Um So, obviously, CT imaging is, is currently the, the main, the mainstay of, of um stroke imaging. Uh whether it, whether it's the noncontrast CT, which is for all patients or the CT angio angiogram, which is for patients for mechanical thrombectomy. The MRI S are, are, are playing an increasingly important role because they are very, so they, they, they're, they're more sensitive than CT S essentially. Um they're also superior for posterior circulation infarcts. Um The, the, the main, the main issue with, with MRI S obviously at the moment is that um the, the ti the time it takes to, to get an MRI scan done and report it is, is much longer than a CT. Um and uh they are more expensive as well, but um they are better at detecting earlier changes um or early earlier ischemic changes and they can play an import important role in patients who have been treated for a stroke um o on the basis of uh clinical symptoms, but the CT scan haven't, hasn't showed anything. So a lot of these patients would have MRI MRI scans just to confirm the stroke as well. Um After treatment basically. Um But the there is an important uh there is uh so obviously with MRI S, you have different sequences. Um You have diffusion. Uh The, the 11 example is diffusion weighted imaging and the other one is flaring, flaring, uh flare, um a flare sequence. Um And essentially these two sequences can be um looked at side by side. Um And if there is a mismatch between the two, uh that can also be a, a way to differentiate between the penumbra or the salvageable um uh salvageable brain tissue uh versus the infarct core. So the MRI scan can work in a similar way to the CT perfusion as well. Um to, to identify whether or not we have um salvageable tissue in patients with stroke uh in patients with strokes. Um And it can also be, be, be useful for mechanical thrombectomy. So, yeah, um this is an example of a diffusion weighted image image um sequence um and this is a flare sequence. So, in conclusion, um obviously imaging is is central to uh stroke diagnosis and uh treatment. Uh Obviously, C CT scans remain the, the main, the main imaging mode. Uh But there is obviously increased um use of MRI scans uh for, for, for diagnosis of, of strokes. Um And uh it's, it's worth, obviously um uh just uh looking out for, for, for how the, how, how A I will play a role um in, in, in stroke management and whether or not it can help uh radiologists identify um basically the number of us of the infarct core more accurately because it, it, it can be quite challenging um quite challenging basically for, for, for radiologists to, to identify it, to identify it accurately. So, yeah, that, that's, that concludes my presentation. Um Thank you so much, Roam. That was a really great presentation, very thought provoking, well laid out. Um So just MRI, are you able to join uh to present your presentation? So, yeah, just give me one sec to figure out how to do it. That's fine. Yeah, that's what I can see just if you can full, can you full screen it. Is that working? Yeah, that's working for me. At least if anyone's having any problems, please do message in the chat and we'll try and sort them. But yeah, that's fine on my end at least. Well, ok. Well, um I'll get started then. Can you hear me? Ok. Yeah, should be fine. Um, so hi guys. Hi, I'm Marriam. It's nice to speak to you today. Um Just before I start, I wanted to say thank you to the uh B RGC for inviting me to present and I hope you enjoy my presentation and thanks to Hassan for his great one as well. Um So yeah, this is the paper that I picked to discuss today. I picked this topic because it's something of interest to me. I'm actually working as a psychiatry trainee, but I've got an interest in dementia and memory issues and frailty related to psychiatric presentations. Um But I also have an interest in radiology because imaging is so important and prevalent in every aspect of medicine. So I kind of wanted to look into its role in something more abstract and I thought this was a good paper to use. It's like a springboard to discuss dementia and its relation with imaging. So just a bit about the paper. So it was published in Molecular Psychiatry, which is a sub journal of nature, which is the globally renowned journal that publishes papers on everything. Um It was written by doctor who is a consultant and um Professor o'brien, they're both old age psychiatrists and researchers affiliated with Cambridge University. And it's a narrative review of multiple studies about MRI and Pet imaging and their use in the diagnosis of dementia. So this is the abstract just copied over here. The main ones that I'm kind of going to go into in this will be Alzheimer's Lewy body dementia and frontotemporal. I've not done as much about vascular dementia in this presentation, but there is a fair bit in the paper if you want to read it. Um But this review, it kind of summarizes findings from uh diagnostic brain imaging studies and it discusses new developments in different types of imaging and the future sort of directions that they hope the field will take and it focuses on MRI and pet scans. So just before going into the contents of the paper, I thought I'll quickly go over some of the basics in the background of dementia itself. So it's a neurocognitive disease and it causes cognitive decline leading to impairments in all aspects of functioning most commonly in memory, understanding awareness, but it can affect anything and it affects around 55 million people worldwide. As of 2020 statistics, it said that someone in the world develops dementia every three seconds and the number of sufferers is expected to be more than double of this. Um In 2050 it's expected to be more than 130 million people worldwide and over 60% of sufferers live in low and middle income countries. This is thought to be because of lack of funding on healthcare, lack of access and have resources available, possibly also lack of knowledge about how to manage dementia as well. Um It's a progressive and irreversible condition and the structural brain changes that happen um do so years before the symptoms present themselves. So it's almost always diagnosed late and why is early diagnosis important because it allows the most appropriate clinical management to be given. You can support the patient and their families and help them understand the condition its nature and expectations about treatment. It can increase the accuracy of prognosis and also identify people who would benefit from any sort of disease modifying therapies as they are developed. Um just going through the most common types of dementia. I won't read the whole slide because I know it's quite text heavy. But just briefly, Alzheimer's is related to the accumulation of amyloid plaques and tout tangles leading to damage and loss of neurons. It can affect anywhere and it's kind of associated with global atrophy, but mainly it does tend to affect the hippocampus, which is involved in memory and the cortex which is involved in thinking and planning. And because of the wide effect and atrophy that is present, there is the wide range of symptoms. So it can be difficult to diagnose and also difficult to differentiate it from other types of dementia and other conditions. Um Vascular dementia, as the name suggests is a result of reduced cerebral perfusion due to strokes or small vessel disease. And the effects on the symptoms depend on which part of the brain is affected by the vascular damage. Um but as a broad overview, the symptoms can generally include things like confusion, difficulty concentrating memory issues, and then dementia with Lewy bodies that's related to, as the name suggests, the formation of Lewy bodies in the neurons which disrupts their function and it can affect multiple areas as well. Usually areas involved with cognition, movement, sleep, and in particular areas involved in visual perception, especially in the occipital lobe. So the symptoms can also be quite wide ranging including changes in alertness, visual hallucinations, parkinsonian symptoms of stiffness, tremors, bradykinesia and sleep disturbances. So this is something that can be seen in psychiatry due to the potential of psychotic symptoms, that can be what a patient may present with with regards to the hallucinations. And then also there's frontotemporal dementia which involves degeneration of the frontal lobe, which is involved in behavior and personality and or the temporal lobe involved in language processing. And again, this is another one commonly seen in psychiatry in particular behavioral variant FTD, which is a subtype which presents with behavior and personality changes. And you can have symptoms like apathy, social withdrawal, impulsivity, emotional blunting and that kind of thing. Um There are some other types of dementia that are less common. Those are conditions like PS P Huntington's dementia or corticobasal degeneration. And you can also have mixed dementia where you can have different types present at the same time. It's quite commonly vascular dementia with another type. Um So when it comes to looking at the images and what structures you focus on, there's a group of structures or a collection of structures in the brain that's called the limbic system. And these are all involved with regulation and processing of emotions, memory behavior. And the main ones as highlighted are the amygdala, hippocampus, thalamus, and hypothalamus. And these are areas that are quite often impacted by neurodegeneration in dementias. So they're often of quite particular interest in imaging and studies. So again, this slide is quite text heavy. So I won't read through all of it and be that guy. Um But one thing I wanted to highlight with regards to these structures in the limbic system is that there is some overlap in the roles of these areas. So all of them are involved with like I said, emotions, memory behavior. But then there are also some other functions that each one has such as spatial navigation in the hippocampus or regulation of autonomic function in the hypothalamus. So it just shows a really wide range of symptoms that you can get with any type of dementia. And how so many parts of your functioning can be impacted and looking at the associated dementia. It's kind of difficult to definitively say because of where a dementia could affect your function. But Alzheimer's involves global atrophy and damage. So all areas can be affected, vascular dementia. The symptoms depend on the area affected by the vascular damage. So any of these areas, none of them or all of them could be affected. So why is imaging useful in dementias? It can be used in both the assessment of suspected dementia and also in determining a diagnosis along with your history taking and other investigations. It can also be used through serial imaging to see any structural changes over time. Um MRI is preferred to CT in these conditions. So why is that? So, MRI has better contrast between soft tissue structures. There's no ionizing radiation from MRI. So it's safer in elderly patients and those who might need multiple scans over the years, it's also able to detect more subtle changes and it can be more detailed. There is also the use of pet imaging, which I'll go into a little bit later. Um with regards to how you can use the imaging, there's structural imaging um as the name suggests to see structures in the brain. So this can be used to exclude any kind of space occupying lesions, strokes, normal pressure hydrocephalus. And it can also be used to differentiate between the types of dementia based on the patterns of atrophy that you see or the changes in white matter or presence of cerebrovascular disease. Then the other um role is through functional imaging, which can see the functioning of the brain. So this can see which parts of the brain are stimulated or active during certain activities or at rest. So this is an example of structural MRI and this is um scans taken from the paper in a frontal um or coronal plain view. So you've got the control, a patient with Lewy body dementia, Alzheimer's and frontotemporal. So if you look at the second one, the DLB, so that shows relative preservation of the hippocampus, which is the circled area, but then you can see some atrophic changes. Then next, you've got Alzheimer's which just shows generalized atrophy. But in particularly you see quite focal changes in the temporal lobe where the hippocampus is, which are the circled areas. And then in frontotemporal dementia, you can see there's quite significant temporal pole atrophy, which is the circle bit over there. In structural MRI S. There is also the means of using something called volumetric analysis. So what does this mean? So it involves measuring volumes of key brain structures and comparing these volumes to the standardized norms based on things like age, gender and normal cranial volume. And so the paper mentions a 2011 study which scanned 100 and 15 patients with different types of dementia against 100 and 20 control patients who were cognitively normal, all of the patients who were scanned, were elderly and also alive. Um So looking at the results, so sensitivity refers to the tests, ability to identify patients correctly who have a disease and specificity is the ability to correctly identify people who don't have the disease. So it does show that using these kinds of maps of ideal volumes of brain areas can be quite useful in identifying patients with different types of dementia and being quite specific about which one which type they have and whether or not you don't have it. However, we do have to be careful when looking at these studies and their results because the volumetric analysis is only useful when looking at established neurodegeneration. So it's not useful in detecting symptoms, detecting dementias before the symptoms have become apparent. And also when you have studies that look at mapping patients with known dementia, they can be inaccurate because they select patients who are known to have very clear cut characteristics of each type of dementia that they're testing. So the results could be overestimated and they're not always reproducible in a wider real world context. Um Also using volumetric analysis and doing serial or sequential imaging over time, you can see the rates of atrophy of different parts of the brain. So in Alzheimer's, the rate of atrophy is four times higher than in control patients. Whereas in dementia with Lewy bodies, there's less overall atrophy. And when you put them together when you've got patients who've got mixed Alzheimer's and Lewy body dementia, there are faster rates of atrophy. So it suggests that the Alzheimer's processes are the driver of this atrophy. Um And of these MRI is functional MRI. So this measures changes in blood flow to different parts of the brain to see which parts are engaged at what times, mostly used at rest because MRI machines are quite clunky and difficult to perform at movement, especially in frail, confused patients. So what this kind of uses as a standardized baseline is something called the DMN or default mode network. This is a network of regions in the brain that tend to show increased activity when the person is not focused on the external environment, but instead they're engaged on internally directed thought. So that's things like daydreaming or recalling memories or planning and that kind of thing. So Alzheimer's has shown reduced activity and reduced connectivity in this default mode network. So cognitive processes are affected like memory, recall or self referential thinking when you're kind of thinking back about yourself. And the paper goes into quite a lot of detail about functional MRI and its use in differentiating between Alzheimer's and behavioral variant um for endoral dementia. And the reason that it's important to be able to differentiate between them is because they can have quite overlapping symptoms with the behavioral changes and cognitive decline. Alzheimer's can present with behavioral symptoms especially in early stages or early onset. So it can be difficult to tell the difference between them. So, functional MRI testing in Alzheimer's shows decreased connectivity in the dorsal visual stream network and lateral and occipital parietal cortex. So what does that mean in English? So the dorsal visual stream network is a pathway that processes visual information related to spatial awareness. So where things are around us and also how to interact with them. And the occipital cortex is involved in visual perception and recognizing objects. And the parietal cortex is also involved in spatial orientation of where things are in space around us. So just to kind of summarize, so understanding where things are in the environment and how to interact with them is affected. On the other hand, behavioral variant shows decreased connectivity in the lateral visual cortical network, lateral occipital and canal cortex and also the auditory system network and angular gyrus. So what does this mean? The lateral visual cortical network involves areas of the brain whose role is uh processing visual information. Again, the occipital cortex is involved in visual perception and object recognition as is the cuneal cortex and then the involvement of the auditory networks, you basically putting it all together. It means that people can struggle with understanding what they see and hear and they may not actually accurately perceive them. So that can also be a particular evidence in psychiatry where they may present a psychotic due to these abnormal audiovisual perceptions and it shows why um physical activity, exercise and stimulating the brain is important because it strengthens these networks and it promotes resilience to neurodegeneration. And so it's why it's kind of so heavily promoted in the aging population. Um So some of the uses of MRI, there's diffusion weighted MRI imaging. So that's related to the transport of water in the brain, there's blood flow and perfusion studies. So that uses injectable contrast or magnetically labeled blood to determine um which areas of the brain have impaired perfusion. And also some studies focus on the blood brain barrier and have shown things such as a breakdown in the barrier and the hippocampus. The paper does explain about these and it's quite interesting but I didn't want to make this overly long complicated. And also these assessments aren't used as often because they're expensive, time consuming, complicated to operate, complicated to interpret and they're not as widely available. So, moving on to pet imaging. So the principle of pet imaging is it uses radioactive tracers to visualize and measure changes in metabolic processes. So FDG pet involves the use of pet imaging and a radioactive glucose analog called fluorodeoxyglucose or FDG. So the pet, oh Sorry, the pet scanner can detect gamma rays from FDG decay and present the distribution of this in the brain and it shows how much glucose is being consumed by certain areas to show which parts of higher or lower activity. So if there's an area with reduced uptake of FDG. It suggests reduced metabolism in that area which then relates to reduced activity of the synapses. And evidence of neurodegeneration and neurodegeneration in itself leads to decreased metabolism because the damaged neurons can't use glucose as effectively. And evidence shows that FDG is very effective at differentiating Alzheimer's dementia from controls. Um so some of the patterns of hypo metabolism, reduce metabolism that is seen in FDG. Pet Alzheimer's shows reduced metabolism in the temporal and parietal lobes. Frontotemporal shows it in the frontal lobe and dementia with Lewy body shows generalized, reduced uptake, but specifically in the occipital region. There is some limited evidence that possibly FDG PET can predict the conversion of mild cognitive impairment into dementia. But the studies that were included in the paper have quite limited sample sizes and there's quite a wide range of sensitivity and specificity. So it's not really accurate. We can't really use it yet. It does imply that like other imaging modalities, it's more useful at determining an established dementia rather than catching it early. Some other limitations are that there are other conditions that can cause patterns of hypermetabolism. So those include things like progressive s palsy, uh autoimmune encephalitis, chronic schizophrenia and alcohol related brain damage. Also, there are difficulties in using FDG pet in diabetic patients as high blood sugar levels can interfere with the uptake of FDG because the glucose competes with the FDG for uptake. Um So like it can lead to less FDG accumulation in the tissues. Also, patients who have really poorly controlled diabetes may have an altered metabolism of how they uptake glucose, which can lead to an altered uh uptake of FDG. So that can complicate the interpretation because the patterns would be atypical. So that's why it's important that any of these images, imaging modalities are used in combination with history and background and other assessments and examinations. It's not enough to solely base a diagnosis on the imaging. So these are some images FDG pet scans in patients. Um There's control Alzheimer's and dementia with Lewy bodies. So if you look, I don't know if you can see my mouse. But if you see the, the first picture in the last row, um there's an arrow pointing to the occipital region in the dementia with Lewy bodies row. So there's reduced uptake of F TGA in the occipital region in dementia with Lewy bodies. And then also if you look at the third picture in each row, you can see the patterns of uptake in the hippocampus. So if you start at the bottom where there's the two arrows, you can see that there's quite preserved metabolism in the hippocampus and then going to the one above it, which is the Alzheimer's patient, there's quite significantly reduced metabolism in the same area which corresponds to the hippocampus. Um So just one more type of imaging I wanted to discuss is amyloid pet imaging. So this is a type of pet imaging that looks at the presence of amyloid proteins in the brain. Um This is a pathology that's associated with Alzheimer's dementia. And it's something that's quite important in the early and kind of specific diagnosis of Alzheimer's especially in early onset or when you want to differentiate it from other dementias. So it involves giving a radioactive tracer that binds to amyloid beta plaques and then picking up the gamma rays that are emitted by the decay of this tracer. And it allows us to see the density and the distribution of the amyloid plaques. And here are some of the traces available for use which I'm not going to attempt to pronounce. Um One handy thing about amyloid pet imaging is the role of serial pet scans to see how the amyloid deposits spread as the disease progresses. So, it's um studies have shown that it tends to start anteriorly in the temporal lobe and then spread to the frontal and medial parietal areas. However, there is um one quite significant limitation in that in 50% of cases of dementia with Lewy bodies, there are also amyloid related pathologies. So you can't use amyloid pet to differentiate Alzheimer's from dementia with Lewy bodies. Some other limitations include the fact that the amount of amyloid deposits present don't have anything to do with when the symptoms of dementia start or how severe the condition is. Also, it can't predict or inform us as to when the dementia started. And there are other pathologies um which involve amyloid deposition that can kind of blur the lines of the diagnosis as well. For example, um C A which involves deposition of amyloid in the walls of blood vessels in the brain and it's associated with increased risk of hemorrhagic stroke. Um just to finish off, then some other uses for pet imaging. So there's also Tau pet imaging. So this is another um modality that can be used in Alzheimer's dementia assessments. So this uses ligands that bind to the neurofibrillary tau tangles and the deposition of Tau can correlate with the progression and the severity of Alzheimer's. So it's thought that this is going to become more important in the future at helping to diagnose and differentiate Alzheimer's and then some other ligands available. There is 11 C UC BJ pet which uses a ligand that binds to a synaptic vessel protein to see the density of the synapse and PK pet, which is used to detect the distribution of neuro inform information, which is thought to be another contributing cause towards people developing dementias. Um So, yeah, that's my presentation. Thank you very much. Thank you so much, Miriam. That was a really, really interesting uh and very thorough presentation as well. Um So now, um excuse me, sorry. So now just if anyone potentially has any questions, they might wanna ask any of our two presenters, maybe for the for the next five minutes. If you can put your questions in the chat, I can read them out. And then hopefully, if I'm already on time, you guys don't mind. We could just answer a couple of questions. So we'll leave it for the next couple of minutes. And if anyone has the question, please do message it in the chat. Uh So I believe this question might be from Miriam. Um where um someone's asking about pet imaging is only used for dementia. So Miriam, could you please um help answer this question for us? Um Sure. I mean, I'm not an expert in, I'll be very honest with you. Um But this is just a topic that I decided to focus on just on the use of pet imaging in dementias, but it's pets really commonly used in cancer in the detection of cancer and evaluating treatment as well. But yeah, I just decided to focus specifically on dementia and that's what this paper was about. Thank you for that. Ok, so it appears we don't have any more questions. So thank you everyone for attending our um session on neuroimaging. Thank you so much to both of our presenters for presenting. They were really great presentations and just to remind everyone again, if, if please, please, please, if you can follow us on our different platforms, we've got a whatsapp group. We've got um our Instagram page and our Facebook page. Um And also if please please, please, everyone's gonna get an email afterwards with regards to um a feedback form. We do read our feedback and it does really help us that if there's any changes you guys might want to the er, events, then please, please, please do um fill out the feedback forms. It does help us a lot and we can hopefully try to improve the sessions for you guys. Um And short with regard to your question about the access to the slides. We um we upload um things on our newsletter on our website. Um So just keep an eye out on there and if that's ok, then everyone. Thank you so much for joining and then hopefully we'll see you next month for our next session. Thanks again. Thanks for both side. Thank you. Thank you guys. Thank you.