Stroke

Question 1

Definition of stroke.

Answer 1

Cerebral vascular accident. Sudden vascular event leading to disruption of blood flow to part of the brain and destruction of surrounding brain tissue. Patients will have a rapid onset of neurological deficits.

Question 2

Transient ischemic attack.

Answer 2

Focal neurological symptoms, similar to stroke, but with resolution of neurological symptoms within 24 hours! Etiology is the same as a stroke. 15% of all strokes are preceded by TIA.

Question 3

Early management of TIA includes:

Answer 3

Imaging, close observation, and blood thinners.

Question 4

Risk factors of a stroke that are potentially modifiable:

Answer 4

HTN, cardiovascular disease, DM (type II), high cholesterol, smoking, alcohol/cocaine use, medication, physical inactivity, obesity, and diet.

Question 5

Risk factors of a stroke that are non-modifiable.

Answer 5

Age (greatest risk), race, gender, family history (stroke, sickle cell disease, genetic predisposition.

Question 6

Early warning signs of a stroke.

Answer 6

Sudden weakness or numbness of face, arm or leg; sudden difficulty speaking or understanding speech; sudden vision change (one eye); unexplained dizziness, unsteadiness or falls; and sudden severe headache.

Question 7

Pathogenesis of ischemic stroke.

Answer 7

Loss blood supply, leading to either no blood flow or reduced blood flow. If no blood flow, we are looking at neuronal cell death (core/infarct); if there is reduced blood flow, we are looking at ischemic penumbra.

Question 8

Ischemic penumbra.

Answer 8

An area surrounding the area of infarct. Inflammatory processes in the penumbra can expand initial lesion. If blood flow is restored to the ischemic area before irreversible damage occurs, the tissue may recover.

Question 9

What three things can all lead to cell death within the ischemic penumbra?

Answer 9

Contents of dead cells spilling out such as poor clearance of glutamate, causing excitotoxicity.
Activated glial and endothelial cells, where free radicals are released, cytokines, chemokines, and enzymes.
Inflammatory process.

Question 10

Atherosclerotic cerebrovascular disease

Answer 10

Plaque forms in vessel walls; carotid and vertebrobasilar system. This will lead to decreased compliance and flow; may form a thrombus which can occlude or emobilze.

Question 11

What is the most common source for an embolism?

Answer 11

The heart, from a-fib

Question 12

Lacunar infarcts

Answer 12

HTN and DM can promote thickening of small vessel walls. We frequently see this occur in the basal ganglia, internal capsule, and pons.

Question 13

Two types of hemorrhagic stroke:

Answer 13

Intracerebral hemorrhage: bleeding from artery into brain parenchyma.
Subarachnoid hemorrhage: bleeding from artery into subarachnoid space.

Question 14

What vessels are typically involved in an intracerebral hemorrhage?

Answer 14

Distal (smaller) vessels; arteriole branches; or penetrating arteries of circle of Willis.

Question 15

What precipitates an intracerebral hemorrhage?

Answer 15

Acute increase in BP or blood flow

Question 16

What typically causes a subarachnoid hemorrhage?

Answer 16

Berry aneurysm: congenital distention at bifurcation, COW.
Venous or cavernous malformation
A-V malformation: direct artery to vein without capillary bed.

Question 17

What occurs during a subdural hemorrhage? What happens if it becomes chronic?

Answer 17

Tearing of bridging veins.
Chronic occurs typically in the elderly where we see cerebral atrophy, causing increased movement between brain and skull.
A minor trauma such as a fall can result in this.

Question 18

What occurs during an epidural hemorrhage?

Answer 18

Torn meningeal artery in periosteal layers of dura.
Typically occurs with traumatic skull fracture.

Question 19

Middle cerebral artery syndrome

Answer 19

Contralateral (UE>LE): hemiplegia, hemianesthesia
Dominant hemisphere: global aphasia
Partial syndromes: can either be superior division or inferior division

Question 20

Anterior cerebral artery syndrome

Answer 20

Contralateral (LE>UE): hemiparesis, hemianesthesia
Occlusion proximal to the anterior communicating artery can cause minimal dysfunction due to collateral flow.

Question 21

Internal carotid syndrome

Answer 21

MCA and ACA symptoms
Symptoms may be minimal due to collateral flow

Question 22

Posterior cerebral artery: thalamic branches

Answer 22

Abnormal sensation: exaggerated, light touch = pain

Question 23

Posterior cerebral artery: occipital branches

Answer 23

Visual changes: homonymous hemianopia, visual agnosia

Question 24

Posterior cerebral artery: temporal branches

Answer 24

Memory loss

Question 25

Posterior cerebral artery: proximal occlusion

Answer 25

Cerebral peduncle: contralateral hemiplegia Red nucleus: contralateral ataxia

Question 26

Lacunar syndrome

Answer 26

Internal capsule: posterior limb will be pure motor; genu will be weak face and dysarthria. Thalamus: posterolateral will be pure sensory. Basal ganglia: movement disorders

Question 27

Vertebral and PICA syndromes

Answer 27

Lateral medullary (Wallenburg's) syndrome: vertigo, nausea, hoarseness, dysphagia; ipsilateral will be ataxia, ptosis, facial, sensory loss; contralateral will be torso and limb sensory loss. Medial medullary syndrome: contralateral will be hemiparesis (arm and leg), proprioception; ipsilateral will be tongue weakness.

Question 28

AICA syndrome

Answer 28

Vertigo/nystagmus Ipsilateral face/contralateral body pain and temp loss Facial weakness Ataxia

Question 29

Superior cerebellar syndrome

Answer 29

Ipsilateral ataxia Contralateral pain/temp loss (body, limbs, face)

Question 30

Basilar artery syndrome

Answer 30

Complete, AKA locked in syndrome: quadriplegia, lower bulbar palsy, mutism; spared: cognition, sensation, and vertical eye movement. Partial: ataxia, clumsiness, weakness

Question 31

Diagnosis for a stroke.

Answer 31

History (timing, pattern of onset, course). CT: fast and convenient, but decreased detection of acute ischemic stroke (hemorrhage will be seen). MRI: detect ischemic within 2-6 hours; can monitory ischemia/evolution of stroke. PET: higher sensitivity, earlier detection; can show areas of hypometabolism or decreased blood flow. Doppler ultrasound: carotid and vertebral arteries blood flow.

Question 32

Cerebral angiography

Answer 32

Invasive procedure; inject radiopaque contrast agent or dye in a vein or artery; series of x-rays are taken; can help to diagnose obstruction or stenosis in vessels.

Question 33

Thrombolytic agent for ischemic stroke.

Answer 33

Tissue plasminogen activatory (t-PA); it significantly in recovery if taken within 4.5 hours. Risk of hemorrhage.

Question 34

Cerebral perfusion for ischemic stroke.

Answer 34

Decreases BP is dangerously high. May try to increase if too low in acute stage.

Question 35

Medical prophylaxis for ischemic stroke includes:

Answer 35

Anticoagulation therapy Control HTN Lipid lowering agents Neuroprotecting Surgery - manage stenotic vessels

Question 36

Medical management for intracerebral hemorrhage.

Answer 36

Control HTN: rapid acting antihypertensive meds Control ICP Manage edema Surgical drainage: large size, neurologic deterioration, often performed with cerebellar hemorrhage due to risk of rapid deterioration.

Question 37

Prognosis of a stroke.

Answer 37

Loss of consciousness is a poor prognostic indicator. Risk of recurrent stroke Recovery: 90% in the 1st 3 months; functional recovery of movement patterns can occur for 5 years.

Question 38

Current research says to focus on what three things?

Answer 38

Minimize damage at onset, control recurrence, and effective rehabilitation.