Stroke Flashcards
What is the definition of stroke?
An acute onset of focal neurological signs/symptoms due to an interruption in the blood supply
What are TIA’s?
Transient ischaemic attacks are sometimes defined as being <24hours of symptoms with complete resolution
What % of TIA’s can show damage on MRI?
50%
2 main subtypes of stroke?
Ischaemic stroke (85% of cases)
Hemorrhagic stroke (15% of cases)
What is ischaemic stroke?
Blood clot stopping blood to an area of the brain.
What is hemorrhagic stroke?
Most common type is intracerebral haemorrhage. In this the weakened/diseased vessels rupture.
Stroke is the 3rd most common cause of mortality in Scotland. True/false?
True
Some risk factors of stroke?
High systolic blood pressure
High BMI
High fasting blood glucose
Smoking
High diet sodium
High LDL cholesterol
What is total anterior circulation syndrome (TACS)?
A large cortical stroke affecting the areas of the brain supplied by both the middle and anterior cerebral arteries.
TACS features?
Hemiplegia involving at least 2 out of face, arm and leg +/- hemisensory loss.
Homonymous hemianopia
Cortical signs e.g. dysphasia
What is partial anterior circulation syndrome (PACS)?
A less severe form of TACS, where only part of the anterior circulation has been compromised.
PACS features?
Hemiparesis (same conditions as TACS - with only partial weakness).
Monoparesis
Homonymous hemianopia
Any 2 of the 3 shown above.
What is Lacunar syndrome (LACS)?
Clinical manifestation of lacunar infarctions. Lacunar infarctions are small infarcts in the deeper parts of the brain (basal ganglia, thalamus, white matter) and in the brainstem.
Cause of lacunar syndrome?
Occlusion of a single petetrating artery. Motor or sensory or both affecting 2 of the face, arm and leg.
What is the prognosis for LACS?
Has the best prognosis of all strokes with 60% of patients and alive and independent in 1 year.
What is posterior circulation syndrome (POCS)?
Occurs in the arteries that supply blood to the back of the brain.
Some features of POCS?
Cranial nerve palsies
Cortical blindness
Cerebellar defects +/- motor sensory signs
What is cortical blindness?
Loss of vision without any ophthalmological causes and with normal pupillary light reflexes due to bilateral lesions of the striate cortex in the occipital lobes.
2 main subtypes of hemorrhagic stroke?
Intracerebral haemorrhage an subarachnoid haemorrhage
Ischaemic cascade definition?
A series of biochemical reactions that are initiated in the brain and other aerobic tissues after seconds to minutes of ischaemia.
Ischaemia core definition?
An area of the brain which has developed necrosis. Cerebral blood flow < 20%
Ischaemic Penumbra meaning?
Area of the brain with reduced cerebral blood flow, but also getting supply of oxygen and glucose from collateral arteries.