Cerebral Infarction (clinical) Flashcards by Sarah Anderson

Define stroke

Is a sudden onset of focal or global neurological symptoms caused by ischema or haemorrhage and lasting more than 24 hours

How well did you know this?

Not at all

Perfectly

What is the two many causes of strokes

Ischaemic 85%

Haemorrhage 15%

How well did you know this?

Not at all

Perfectly

Define Transient ischaemic attack

Term used when stroke symptoms resolve within 24 hours

Most TIAs last within 1-6mis

How well did you know this?

Not at all

Perfectly

What is the causes of ischaemic stroke

Large artery atherosclerosis (e.g. Carotid)
Cardioembolic (e.g. atrial fibrillation)
Small artery occlusion (Lacune)
Undetermined/Cryptogenic
Rare causes:
-Arterial dissection
-Venous sinus thrombosis

How well did you know this?

Not at all

Perfectly

What is the causes of haemorrhage stroke

Primary intracerebral hemorrhage

Secondary hemorrhage

Subarachnoid hemorrhage
Arteriovenous malformation

How well did you know this?

Not at all

Perfectly

What is the cause of a primary intracerebral haemorrhage

Hypertension

How well did you know this?

Not at all

Perfectly

What is the pathophysiology of stroke

Failure of cerebral blood flow to a part of the brain due ti interruption of the blood supply to the brain resulting in various degrees of hypoxia

Prolonged hypoxia becomes anoxia (no oxygen)

Anoxia then causes infarction leading to complete cell death and necrosis

This is a stroke

How well did you know this?

Not at all

Perfectly

What further damage can result from a stroke

Oedema

Secondary haemorrhage

How well did you know this?

Not at all

Perfectly

What affect does hypoxia have on the brain

Stresses the brains cell metabolism

How well did you know this?

Not at all

Perfectly

Define ischemic penumbra

the penumbra is the area surrounding an ischemic event “ischaemic core” such as thrombotic or embolic stroke

How well did you know this?

Not at all

Perfectly

What is the non modifiable risk factors for a stroke

Previous stroke
Being old
Being male
Family history

How well did you know this?

Not at all

Perfectly

What is the modifiable risk factors for a stroke

Hypertension

Smoking

Cholesterol (diet)

High BMI/obesity

Alcohol

Diabetes

Impaired cardiac 
function

Oral contraceptive

Hyper-coagulable states

How well did you know this?

Not at all

Perfectly

What is the most important modifiable risk factor for stroke

Hypertension

as stroke risk is directly related to your blood pressure levels

How well did you know this?

Not at all

Perfectly

How does hypertension increases your stroke risk

Chronic hypertension worsens atheroma and affects small distal arteries

How well did you know this?

Not at all

Perfectly

What contributes to the LDL- Cholesterol deposition in the arterial wall

Hypertension
Smoking
Diabetes

How well did you know this?

Not at all

Perfectly

What is involved in the anterior circulation

From: 2 x Internal carotid arteries

2 x Anterior Cerebral Artery (ACA)
2 x Middle Cerebral Artery (MCA)

How well did you know this?

Not at all

Perfectly

What is involved in the posterior circulation

From: 2 Vertebral arteries
1 Basilar

3 pairs of cerebellar arteries
2 Posterior cerebral artery (PCA)

How well did you know this?

Not at all

Perfectly

How does the arterial blood supply anastomose in the brain

Through the circle of willis via anterior and posterior communicating arteries

How well did you know this?

Not at all

Perfectly

Where does the borderzone anastomoses occur

between peripheral branches of
anterior, middle and posterior
cerebral arteries

How well did you know this?

Not at all

Perfectly

What is symptoms of arterial cerebral artery

Contra-lateral:

paralysis of foot and leg

sensory loss over foot and leg

impairment of gait and stance

How well did you know this?

Not at all

Perfectly

What is potential symptoms of middle cerebral artery occlusion

Contralateral:

paralysis of face/arm/leg
sensory loss face/arm/leg
homonymous hemianopia

Gaze paralysis to the opposite side

Aphasia if stroke on dominant left side

Unilateral neglect and agnosia for half of external space if non dominant stroke

How well did you know this?

Not at all

Perfectly

What side of the brain is usually a dominant stroke

Left - as most people usually right handed

Would be right dominance if patient is left handed

What is the specific symptom of middle cerebral occlusion on the dominant (left) side -patient is right handed

hemiplegia - paralysis on one side of the body

homonymous hemianopia,

dysphasia - language disorder

What is the specific symptom of middle cerebral occlusion on non dominant stroke (right side)
- the patient is right handed

Left Hemiplegia

Homonymous hemianopia

Agnosia - neglect syndrome

Visual agnosia
sensory agnosia
Anosagnosia (denial of hemiplegia)
Prosopanosia (failure to recognise faces)

Where is Broccas area and wernickes area both located if patient is right handed

On left side - both found on dominant side of the brain

If patient is left handed and presents with a stroke with speech difficulties, what hemisphere is affected

``` Right hemisphere (as presents with right sided dominance due to left handedness) ```

What supplies blood supply to the basal ganglia

Middle cerebral artery with branches to smaller arteries | medial and lateral lenticulostriate

Where does a lacunar ischaemic stroke occur

In the small arteries suppling the basal ganglia

What is symptoms of lacunar stroke

Pure motor stroke Pure sensory stroke Dysarthria - clumsy hand syndrome Ataxic hemiparesis

What is a lacunar stroke devoid of

Cortical signs

What does the posterior circulation supply

Brain stem Cerebellum Thalamus Occipital and medial temporal lobes

What is the symptoms of brain stem dysfunction

Coma, vertigo, nausea/vomiting, cranial nerve palsies, ataxia - loss of full body movement Hemiparesis, hemisensory loss Crossed sensori-motor deficits Visual field deficits

What is the purpose of ischaemic stroke therapies

Restore blood supply. Prevent extension of ischemic damage. Protect vulnerable brain tissue

What is the treatment administrated for ischaemic stroke

Aspirin Heparin Tissue Plasminogen Activator (TPA) Thrombectomy Stroke unit

What is the most effective stroke treatment

Thromboectomy

What is the 8 different components of a stroke unit

``` Clinical staff Stroke nurses Physiotherapists Speech and Language therapists Occupational therapists Dietitian Psychologist Orthoptist ```

What is a tissue plasminogen activator

Enzyme that helps dissolve blood clots

What is the strict criteria for tissue plasminogen activator

< 4.5 hours from symptom onset. Disabling neurological deficit. Symptoms present > 60 minutes. Consent obtained

What is the exclusion criteria for IV tissue plasminogen activator

Anything that increases the possibility go haemorrhage BP >185 systolic or >110 diastolic Glucose <2.8 or > 22mmol/L

What is the disadvantages of tissue plasminogen activator

Hard to find the balance and not cause an over bleed Benefit from TPA declines with time

What is the four classifications of stroke

Total Anterior Circulation Stroke (TACS) Partial Anterior Circulation Stroke (PACS) Lacunar Stroke (LACS) Posterior Circulation Stroke (POCS)

What is presentation of LACS

+/- Motor (2/3 face, arm leg) +/- Sensory loss (2/3 face, arm, leg)

What is presentation of PACS

+/- Motor (2/3 face, arm leg) +/- Sensory loss (2/3 face, arm, leg) Will have 1 of: - Hemianopia - Dysphasia - Neglect

What is the presentation of TACS

+/- Motor (2/3 face, arm leg) +/- Sensory loss (2/3 face, arm, leg) Will have Hemianopia and Dysphasia or Neglect

What is presentation of POCS

+/- Motor (2/3 face, arm leg) +/- Sensory loss (2/3 face, arm, leg) +/- Hemianopia/Dysphasia /Neglect Brain stem or cerebellar signs

What are TIAs

Warning sign of a stroke - with 10% stroke recurrence within the first 2 weeks

What is an effective treatment for carotid artery stenosis to prevent a stroke occurring

Carotid endarterectomy

What is preventative treatment to reduce the relative risk of a stroke

``` Antiplatelets Antihypertensives Statins Endarterectomy Warfarin - for AF ```

What investigations occur for a stroke

Routine blood test CT/MRI head scan EEG ECHO Carotid doppler ultrasound Cerebral angiogram/venogram Hyper-coagulable blood screen

What is the gold standard investigation for stroke and why

CT - quick - can determine if ischaemic or hemorrhagic

How is biopsy useful in stroke investigation

Temporal artery biopsy can show giant cell arthritis

What can be misdiagnosed as a stroke

Post-ictal states (e.g. Todd’s paralysis) Hypoglycemia Intracranial masses Vestibular disease Bell’s palsy Functional hemiparesis Migraine Demented patients with UTIs

What is the management of an acute stroke

Prevention of stroke recurrence. Prevention of complications related to stroke. Rehabilitation. Re-integration into the community

Define lipoyhallnosis

Small-vessel disease in the brain, that due to the sensitivity of hypertension results in lacuna stroke