Neuroscience Week 6: Cerebrovascular disease Flashcards

Question

Identify

Answer 1

Watershed infarction at MCA/PCA territory

Answer 2

Watershed infarction at ACA/MCA territory

Answer 3

* Cardiac mural thrombi are frequent cause of emboli (e.g. in patients with atrial fibrilation, myocardial infarction or valvular disease). * Thromboemboli can also originate in carotid atheromatous plaques * Venous emboli can cross into the arterial circulation via a patent foramen ovalae (deep venous thrombosis of legs or fat embolism)

Answer 4

Commonly affect MCA

Answer 5

* Superimposed on atherosclerotic plaques in carotid bifurcation, MCA origin, and ends of the Basilar artery * can also be caused by hypertension-induced thrombotic occlusions of small penetrating arteries (lacunar infarcts)

Answer 6

Evolve into hemorrhagic infarcts especially when there is reperfusion of ischemic tissue (either through collaterals or after emboli have dissolved)

Answer 7

Cerebral infarction A. Section of the brain showing a large, discolored, focally hemorrhagic region in the left middle cerebral artery distribution (hemorrhagic, or red, infarction) B. An infarct with punctate hemorrhages, consistent with ischemia-reperfusion injury, is present in the temporal lobe C. Old cystic infarct shows destruction of cortex and surrounding gliosis

Answer 8

Cerebral infarction A. Section of the brain showing a large, discolored, focally hemorrhagic region in the left middle cerebral artery distribution (hemorrhagic, or red, infarction)

Answer 9

Cerebral infarction B. An infarct with punctate hemorrhages, consistent with ischemia-reperfusion injury, is present in the temporal lobe

Answer 10

Cerebral infarction C. Old cystic infarct shows destruction of cortex and surrounding gliosis

Answer 11

1. Acute 2. Subacute & 3. Remote

Answer 12

* Acute * Initially appears pale and edematous soft to palpation (first 48 hours) * Edema can cause death by subsequent herniation

Answer 13

* Subacute * Becomes gelatinous with more obvious delineation from normal tissue (2-10 days)

Answer 14

* Remote * Tissue liquefies, leaves a fluid-filled cavity lined by dark tissue (10 days - beyond)

Answer 15

Acute stage * red neurons * Edema (Vacuolation of neuropil) * Neutrophils present at about 24 hours, then disappear mostly by 48 hours)

Answer 16

Subacute * Macrophages appear and predominate * Tissue defect is obvious * Astrocytes proliferate at the edge and become reactive (1 week)

Answer 17

Remote * Cavity will contain glial fibers, new capillaries and connective tissue fibers

Answer 18

Most common in mid to late adult life (peak at 60 years of age)

Answer 19

Most commonly caused by hypertension

Answer 20

* 70-80% of hypertensive hemorrhages occur in the lenticulostriate and thalamostriate arteries which supply the basal ganglia, internal capsule and thalamus * 5-10% of hemorrhages arise in the lobar white matter of the cerebral hemispheres

Answer 21

* ~15-20% of all cases * include the basal pons and cerebellar white matter

Answer 22

Hemorrhages into the pons are nearly always fatal, while hemorrhages into the cerebellum can cause rapid decreases in pressure in the posterior fossa and are a neurosurgical emergency but are frequently survivable

Answer 23

* hypertensive hemorrhages are the result of hypertension-induced degenerative changes in arterial or arteriolar walls probably combined with increased perfusion pressure * The role of (charcot-Bouchard) microaneurysms has been difficult to substantiate in most cases

Answer 24

* Hypertensive hemorrhages typically give rise to large hematomas * Ventricular extension of the hematoma is common in fatal cases of hemorrhage in the basal ganglia, thalamus or pons * Mass effect occurs due to both the hematoma and surrounding edema * This expansile effect often is severe enough to cause herniation * Resolution of a survivable hemorrhage may leave a surprisingly small tissue defect

Answer 25

* β-amyloid can also deposit around blood vessels * most commonly the leptomeninges (this is not always a feature of Alzheimer's Disease) * Can be a source of intraparenchymal hemorrhage

Answer 26

* Most common cause is a rupture of saccular aneurysms (circle of Willis and proximal MCA in ~90%) * they may be in multiple (in up to 15-20% of cases) * Other causes can be vascular malformation * and * Trauma

Answer 27

* Occur at time of increase in intracranial pressure (e.g. defacation or orgasm) * Thunderclap headache followed by loss of consciousness

Answer 28

Saccular aneurysms are due to weakening and thinning of the arterial wall with aneurysmal dilation Lack of muscular wall and intima elastic lamina (sac is lined by thickened hyalinized intima)

Answer 29

Increased risk in patients with polycystic kidney disease and extracellular denetic disorders (Ehler-Danlos)

Answer 30

* The size on an aneurysm is important (~0.5-1cm diameter is most likely to rupture) * Rebleeding is common if the aneurysm is not surgically clipped or occluded * Intracerebral hemorrhages result from rupture of an aneurysm directly into brain parenchyma (and/or ventricles)

Answer 31

* Secondary infarction which usually is attributed to vasospasm * Arachnoid fibrosis which his due to the organization of hemorrhage in the meninges in patients who survive * Later sequela of arachnoidal fibrosis can include hydrocephalus due to interference with the flow of CSF

Answer 32

High mortality (25-30% die within 24 hours, 50% by one month, and 60% by 1 year) For those alive after 6 months approximately 70% have no major neurological deficits, 20% have partial neurological deficits and 10% have a permanent disability

Answer 33

Arteriovenous malformation (AVM) is the most common type and more dangerous

Answer 34

Arteriovenous malformation

Answer 35

are complex direct shunts from the arterial to the venous system with intervening gliotic brain parenchyma

Answer 36

may present with seizures (from local ischemic damage to "vascular steal" from cerebral cortex in the area of the shunt prior to developing hemorrhage

Answer 37

AVMs typicallyt involve both the arachnoidal and intraparenchymal vessels They have high flow and arterial pressures that predispose them to rupture and hemorrhage which may be intraparenchymal, subarachnoid or both

Answer 38

These hemorrhages are often massive and frequently fatal (more hypertensive/amyloid etiologies in a young person)

Answer 39

Hypertension causes hyaline sclerosis of deep penetrating arteries and arterioles that supply basal ganglia, hemispheric white matter and brain stem

Answer 40

Small vessels

Answer 41

* intracerebral hemorrhage * Lacunar infarcts * Rupture of a small-caliber penetrating vessel * Acute hypertensive encephalopathy

Answer 42

* small cavity infarcts in basal ganglia and thalamus, internal capsulel, deep white matter and pons * Caused by occlusion of small penetrating branches (most commonly the lenticulostriate vessels

Answer 43

small hemorrhage that leaves a slit-like cavity (slit hemorrhage)

Answer 44

* caused by diastolic BP increases \>130 mmHg * Characterized by increased intracranial pressure and global cerebral dysfunction * Brain edema (herniation in some cases) * Petechia and fibrinoid necrosis of arterioles in gray and white matter

Answer 45

* Caused by inflammatory processes involving blood vessels * Infectious arteritis (aspergillosis, herpes zoster, cytomegalovirus) in immunosuppressed patients

Answer 46

* Common forms of Vasculitis * which are more frequent in older people and women and is associated with polymyalgia rheumatica

Answer 47

* primary angiitis of the CNS affecting multiple parenchymal and subarachnoid vessels * characterized by chronic inflammation, multinucleate giant cells and vessel wall destruction * Present as diffuse encephalopathy with cognitive dysfunction

Answer 48

* Giant Cell (temporal) Arteritis * Disruptions of the elastic lamina with inflammation and giant cells

Neuroscience Week 6: Cerebrovascular disease Flashcards

(79 cards)