there are two main types of stroke a hemorrhagic stroke which occurs when an artery ruptures and bleeds within the brain and an ischemic stroke which occurs when an artery gets blocked hemorrhagic strokes can be further split into two types an intracerebral hemorrhage which is when bleeding occurs within the cerebrum and a subarachnoid hemorrhage which is when bleeding occurs between the pia mater and the arachnoid matter of the meninges the inner and middle layers that wrap around the brain we'll be focusing on intracerebral hemorrhages which are more common an intracerebral hemorrhage that involves just the brain tissue is called an intraperichymal hemorrhage whereas if the blood extends into the ventricles of the brain which stores cerebrospinal fluid is called an intraventricular hemorrhage the brain has a few regions the most obvious is the cerebrum which is divided into two cerebral hemispheres each of which has a cortex and outer region divided into four lobes including the frontal lobe the parietal lobe the temporal lobe and the occipital lobe there are also a number of additional structures including the cerebellum which is down below as well as the brain stem which connects to the spinal cord the right cerebrum controls muscles on the left side of your body and vice versa the frontal lobe controls movement and executive function which is our ability to make decisions the parietal lobe processes sensory information which lets us locate exactly where we are physically and guides movement in a three-dimensional space the temporal lobe plays a role in hearing smell memory as well as visual recognition of faces and language finally there's the occipital lobe which is primarily responsible for vision the cerebellum helps with muscle coordination and balance and finally there's the brain stem which plays a vital role in functions like heart rate blood pressure breathing gastrointestinal function and consciousness [Music] the brain receives blood from the left and right internal carotid arteries as well as the left and right vertebral arteries which come together to form the basilar artery the internal carotid arteries turn into the left and right middle cerebral arteries which serve the latter portions of the frontal parietal and temporal lobes of the brain each of the internal carotid arteries also gives off branches called the anterior cerebral arteries which serve the medial portion of the frontal and parietal lobes and connect with one another with a short little connecting blood vessel called the interior communicating artery meanwhile the vertebral arteries and basilar arteries give off branches to supply the cerebellum and the brain stem in addition the basilar artery divides to become the right and left posterior cerebral artery which mainly serves the occipital lobe and some of the temporal lobe as well as the thalamus finally the internal carotid arteries each give off a branch called the posterior communicating artery which attaches to the posterior arteries on each side so together the main arteries and the communicating arteries complete what is called the circle of willis a ring where blood can circulate from one side to the other in case of a blockage there are a few ways that an intracerebral hemorrhage might happen the most common one is through hypertension or high blood pressure hypertension can lead to various vessel wall abnormalities hypertension can lead to hyaline arteriolosclerosis which results from hydrostatic pressure pushing proteins out of the blood vessel lumen and into the interstitial space within the blood vessel walls over time as more of these proteins deposit into the walls the blood vessels become more stiff and brittle and therefore more vulnerable to rupture hypertension can also cause tiny bulges in the walls of the small arteries called microaneurysms these microaneurysms are called charcoal bouchard aneurysms and they're more likely to be found on small arteries like lenticulostriate vessels which arise from the anterior part of the circle of willis and supply the basal ganglia intracerebral hemorrhages are sometimes associated with arteriovenous malformations which are a tangle of blood vessels that directly connect an artery to a vein a bit like a capillary bed but with much much larger blood vessels over time these abnormal vessels can rupture causing a hemorrhagic stroke intracerebral hemorrhages are also associated with conditions that damage the arteries in the cerebrum themselves like vasculitis a disease where inflammation of the blood vessel walls occurs vascular tumors like hemangioma which is a benign vascular tumor of the endothelial cells of the blood vessels and cerebral amyloid angiopathy which is a degenerative disease where abnormal protein deposits in the walls of the arterioles make them less compliant intracerebral hemorrhage can also be secondary arising after an ischemic stroke an ischemic stroke is caused by a blockage of blood flow to a part of the brain and within hours it usually leads to brain tissue death arteries within the ischemic tissues are themselves made up of endothelial cells that die off and that means that if there's reperfusion or return to blood flow there's an increased chance that the damaged blood vessels might rupture causing a hemorrhage if this happens there's bleeding into dead tissue and it's called a hemorrhagic conversion regardless of the cause once there's an intracerebral hemorrhage blood starts spewing from the damaged blood vessels creating a pool of blood which increases pressure in the skull and puts direct pressure on nearby tissues and blood vessels it also means that less blood is flowing downstream to the cells that need it which leave the downstream tissues deprived of oxygen-rich blood healthy tissues can die from both the direct pressure and the lack of oxygen within a few hours increased pressure within the skull can also lead to brain herniation which is when the brain moves across structures in the skull these structures include the falx cerebri which divides the two halves of the brain the tentorium cerebelli which divides the occipital lobes from the cerebellum and the foramen magnum which is the hole in the base of the skull where the spinal cord connects to the brain stroke symptoms depend on the exact part of the brain that is affected for example an anterior or middle cerebral artery stroke can cause numbness and sudden muscle weakness if a stroke affects the bronchus area which is usually in the left frontal lobe or the wernicke's area which is usually in the left temporal lobe then it can cause slurred speech or difficulties understanding speech respectively if there's a posterior cerebral artery stroke then it can affect vision an acronym to remember some common stroke symptoms is fast facial drooping arm weakness speech difficulties and time time is obviously not a symptom but just a reminder to get help as quickly as possible to minimize cell injury and maximize the chance of a full recovery to diagnose and confirm the location in size of a hemorrhagic stroke medical imaging with a ct or mri can be used also angiography which uses contrast injected into the blood can help to visualize the exact location where blood accumulates in the brain tissue medical treatment of an intercerebral hemorrhage includes using drugs that help control hypertension and relieve intracranial pressure in terms of surgery a craniotomy is often helpful at relieving intracranial pressure when there's a bleed near the surface of the skull in a cradiotomy part of the skull bone is removed to drain any accumulated blood and relieve pressure alternatively if there's a bleed that's located deep in the brain tissue stereotactic aspiration can be done to aspirate off blood and relieve intracranial pressure stereotactic aspiration is done under a ct scanner to help guide a needle to the exact spot where the blood needs to be drained alright as a quick recap an intracerebral hemorrhage is a type of hemorrhagic stroke where an artery breaks within the cerebrum the result is a pool of blood forms which increases intracranial pressure and downstream tissue gets deprived of oxygen-rich blood intracerebral hemorrhages can be treated with medications aimed at controlling the high intracranial pressure as well as surgical interventions like craniotomy or stereotactic aspiration which can help remove the pool of blood the goal is to identify symptoms and to re-establish blood flow to prevent long-term damage to help remember this a common acronym is fast facial drooping arm weakness speech difficulties and time helping current and future clinicians focus learn retain and thrive learn more you