Stroke: Introduction and Types | Clinical Neurology
Aug 26, 2023
Stroke: Introduction and Types | Clinical Neurology
This video “Stroke: Introduction and Types” is part of the Lecturio course “Clinical Neurology” ► WATCH the complete course on http://lectur.io/clinicalneuro http://lectur.io/medicalpremium https://app.adjust.com/z21zrf https://app.adjust.com/b01fak http://lectur.io/subscribe http://lectur.io/playlists https://www.facebook.com/lecturio.med …https://www.instagram.com/lecturio_me …
Content
0.752 -> In this lecture, we're going to talk about stroke
3.382 -> and this will be our introduction to stroke.
6.647 -> This is a really important lecture, a critically important topic.
11.497 -> We see this a lot clinically and need to evaluate this in clinical vignettes.
16.41 -> Let's start with, what is a stroke?
19.297 -> Stroke is a disease that affects the arteries leading to and within the brain.
25.466 -> Strokes occur when blood vessels that carry oxygen and nutrients to the brain
30.519 -> are either blocked by a blood clot in a setting of an ischemic stroke,
34.941 -> or become leaky and burst or rupture, in the situation of a hemorrhagic stroke.
40.96 -> Strokes are really important to understand.
43.488 -> We're going to walk through the pathophysiology, the clinical presentations,
47.19 -> the evaluation, and workup for patients who present with stroke.
52.13 -> When we think about the causes or types of strokes, there are two types of stroke.
57.802 -> The first is ischemic stroke,
60.551 -> and this develops as a result of a blood clot for any number of reasons.
65.671 -> When there's a clot in an artery, there is reduced perfusion
69.451 -> and we can see that in the schematic here,
72.191 -> reduced perfusion in the lenticulostriate arteries leads to death of those cells,
78.644 -> of those neurons and astrocytes and loss of neurologic function.
83.111 -> Patients present with that loss of neurologic function
86.21 -> and our evaluation with imaging and other studies
89.753 -> are to find this area of ischemic or infarcted tissue,
93.896 -> and intervene as soon as possible.
96.722 -> Once the tissue has died and the cells have been lost,
100.239 -> function cannot be recovered and during the recovery process,
104.404 -> we look to recruit other areas of brain to fill in that lost function.
109.148 -> And that's ischemic stroke.
111.387 -> The second type of stroke is a hemorrhagic stroke.
114.721 -> This is the leaky blood vessel stroke or bursting or rupturing of a blood vessel
120.198 -> results in leaking of blood into the brain, and you can see that here in this schematic.
125.832 -> The buildup of blood results in inflammation
128.685 -> and there's an inflammatory response
130.512 -> that increases the total amount of water and cells that are in the brain,
134.921 -> that can compress the nerves and blood vessels
138.371 -> and result in secondary ischemia, as well as loss of nerve function
143.488 -> and cell function, and ultimately cell death and that same loss of neurologic function.
149.995 -> With hemorrhagic strokes, we see a greater likelihood of recovery
153.456 -> because the ischemia that occurs is a secondary process,
157.923 -> but we can still see substantial neurologic deficits.
161.488 -> Our goal when evaluating either an ischemic or hemorrhagic stroke
165.252 -> is to make the diagnosis as soon as possible
168.036 -> and to intervene appropriately depending on the type of stroke that the patient is suffering.
173.737 -> In general, we see that ischemic strokes are much more common.
178.585 -> About 85% of patients who are presenting with a stroke will be suffering an ischemic stroke,
184.684 -> a clot in some artery going to the brain, the cerebrovascular system.
189.861 -> An important minority of stroke about 15% of strokes will be the hemorrhagic strokes,
196.228 -> where weakening of the blood vessel results in rupture of the blood vessel bleeding
201.027 -> in and around the brain in neurologic dysfunction for that reason.
204.872 -> We're going to spend a lot of time talking about each type of stroke when patients present,
209.565 -> odds are, we're worried about an ischemic stroke,
212.688 -> but we need to be mindful of those patients presenting with a hemorrhagic lesion.
217.33 -> And this is a good opportunity to talk about terminology.
221.068 -> When we talk about hemorrhages in the brain, there are both intracranial hemorrhages
226.192 -> and that's bleeding anywhere inside the calvarium, the skull.
230.781 -> And then there's intracerebral hemorrhage,
233.199 -> that's bleeding inside the cerebrum, inside the cortex the brain itself.
237.413 -> So, when we think about the types of hemorrhages that we can see in the nervous system,
242.198 -> there's intracerebral or intraparenchymal hemorrhage,
245.295 -> that's hemorrhage inside the brain tissue; and subarachnoid hemorrhage.
249.026 -> Those are both strokes or types of hemorrhagic stroke.
252.96 -> We can also see bleeding outside of the brain but inside the calvarial vault
257.596 -> and that includes subdural hemorrhage, epidural hemorrhage, and other types of hemorrhage.
262.976 -> Those are not considered strokes, but are important types of intracranial hemorrhage.
267.824 -> Some important terminology as we embark on learning about stroke.
Source: https://www.youtube.com/watch?v=LtH_cGLn6w4
