Cerebrovasclar Disorders Flashcards
What is a cerebrovascular disorder?
Damage (block/break) to blood vessels resulting from an underlying vascular disease
Why are CVDs the 3rd most common cause of death in developed countries?
CVD is very affected by lifestyle and environmental factors (e.g. high blood pressure - stress/cholesterol)
What does the brain need an uninterrupted supply of? Why?
O2 and glucose via the blood
The brain has no reservoir; needs >20% of entire O2 for normal functioning (children need up to 50%)
The term for cholesterol?
Hyperlipidermia
What are risk factors for CVD that you can’t control?
Age (older = higher risk due to normal deterioration) Family history (hx of strokes) Gender (more likely in men)
Risk factors for CVD you can control?
Hypertension Cholesterol Smoking Overweight Poor diet + no exercise Excessive alcohol (ETOH)
Medical conditions which are risk factors for CVD?
Heart disease (atrial fibrillation - irreg <3beat)
IHD - ischemic <3 disease
Diabetes
TIA - transient ischemic attack
What is a precursor to having a stroke (warning sign)?
TIA
Anoxia and Hypoxia?
Anoxia: total deprivation of O2
Unconscious/dead
Hypoxia: reduced supply of O2
Impaired concentration, STM, new learning & judgement
*Sleep apnoea, chronic obstructive pulmonary disease
Lesion:
Discontinuity of brain tissue (almost always loss in fx)
- darker/lighter area (depending on scan)
- demyelination may look similar to lesion on scan
Ischemia:
Inadequate blood supply
Infarct:
Area of dead cells caused by ischemia
Are ischemia and hypoxia the same?
Hypoxia = referring to event (resulting in either semi-perm or permanent cell death) Ischemia = also inadequate blood supply, but in other contexts too (can refer to both hypoxia and anoxia)
Necrosis
Irreversible neuronal cell death
4-6 anoxia
Severe hypoxia (possibility)
8-10 non-severe hypoxia (possibility)
How can blood supply be impaired?
Anoxia & hypoxia
Increase ICP suddenly
Blood spilling out of blood vessel (toxins interfere w/ brain metabolism)
Area of brain blood vessel supplies dictates symptoms
2 types of hydrocephalus?
- Communicating: blood mixes with CSF & interferes with reabsorption
- Obstructive: blocked CSF circulation
What causes obstructive hydrocephalus?
Kids - stenosis (artery narrowing)
Adults - tumors infiltrating ventricles
Breakdown of CVAs:
TIA - collectively called ischemia: short-lasting insufficient blood supply (no necrosis)
Infarction - severer loss of blood flow (necrosis)
Haemorrhage - bleeding & displacement of brain (more severe - permanent damage/death)
Infarcts?
Thrombosis
Embolism
Haemorrhages
Intracerebral
Subdural
Aneurysm
AVM
Critical distinction between ischemic/haemorrhagic:
Ischemic: blood thinner breaks down clots = blood supply restored
Haemorrhagic: blood thinner = death
Symptoms of TIAs:
Motor, sensory or cognitive signs (sudden onset):
- unilateral weakness/tingling in face/limbs
- disorientation
- normal cog. functioning loss (language, visual disturbance)
- normal motor functioning (weakness,slurred speech)
Symptoms of anterior TIA?
Brief clumsiness or limb weakness, dysarthria (muscles used for speech are weak = slowed/slurred speech), aphasia
Symptoms of posterior TIA?
Dizziness, neglect, double vision, numbness or weakness of extremities
Most common cerebral infarction?
Unilateral MCA
Blockage of cerebral circulation:
Level of <3: entire brain
Carotid artery: anterior & middle cerebral circulation
Vertebral artery: posterior circulation
Coronary thrombosis?
Heart attack
Cerebral thrombosis?
Stroke
Lacunar infarction
Due to blockage of very small vessels
Deep in brain = usually pure motor & sensory deficits
Risk-factors: hypertension & diabetes
What is the most common neuropathological process?
Atherosclerosis
- build up of fat on artery walls
- worse at bifurcation of arteries (common carotid)
Thrombosis: why do clots form?
Deviation from normal platelet action
Antithrombotic agent?
Asprin
Common cause of haemorrhagic CVA?
Rupturing of aneurysm
Usually anterior of brain involved:
Embolism
Haemorrhage
2 types of haemorrhages
Intracerebral: localized to L/R (defective artery bursts)
Subarachnoid: diffuse effects (caused by hypertension/defective blood vessels)
Where do about 1/2 aneurysms take place?
Middle carotid artery
AVM
Arteriovenous Malformation
tangle of abnormal blood vessels, communication between arteries and veins effected therefore abnormal blood flow
-headache + vague cognitive complaints
-more serious: slow bleeding
General Ischemic CVA
Feeling strange + collapse with unilateral weakness No H,N,V Focal neurological signs No ICP Tx: blood thinner
General Haemorrhagic CVA
While awake H,N,V Global neurological signs Papilledema (raised ICP) Blood thinners = death
Left hemisphere
Language & symbolic processing
- Broca’s area, Wernicke’s area, connections between them
Right hemisphere
Visuospatial abilities
Rhythmic processing
Non-verbal processing
Frontal cortex
Motor strip
Executive deficits
Personality change
Emotional change
Parietal region
Calculations
Symbolic gestures/actions
Left/right disorientation
Occipital cortex
Visual processing
Object recognition
Deep temporal
Episodic memory
Verbal/semantic memory
Angiograpgy
Diagnosis of aneurysms, AVMs, artery occlusion, stenosis
