10- stroke Flashcards
3 types of stroke
- ischaemic (thromboembolic)
- haemorrhagic (intracerebral or subarachnoid)
- dissection/venous sinus thrombosis/hypoxic brain injury
2 main principles of stroke management
- within thrombolysis window (4 hours)
- determine if bleed with CT scan
how to image stroke
- CT shows blood as bright white
- MRI shows ischaemia as high signal areas
symptoms anterior cerebral artery infarct
- contralateral lower limb weakness
- contralateal sensory changes
- urinary incontenence (paracentral lobules)
- apraxia (left frontal)
- dysarthria/aphasia (frontal lobe)
- split brain (corpus callosum)
stroke definition
neurological deficit caused by injury of CNS by vascular cause, including cerebral infarction, intracerebral haemorrhage or SAH
TIA definition
transient episode of neurological dysfunction caused by focal brain, spinal cord, or retinal ischaemia without acute infarction
risk factors stroke
HT, smoking, DM, heart disease, TIA, carotid bruit, PCV, COAC, alcohol, clotting disorders
what is apraxia
inability to complete motor planning
symptoms proximal MCA infarct
-all branches (lenticulostriate/distal) affected
- contralateral hemiparesis (due to internal capsule is affected)
- contralateral sensory loss (face and arm, can be more if internal capsule affected)
- contralateral homonymous hemianopia without macula sparing as both superior and inferior optic radiations are destroyed
- global aphasia
- contralateral neglect (right parietal lobe)
what is contralateral neglect
cannot acknowledge the other side of the body
distinguishing feature of lenticulostriate stroke
does not cause cortical features eg. neglect of aphasia
what is a lenticulostriate stoke
lentoculostriate artery occluded, lacunar stroke. destruct internal capsule and basal ganglia
types of MCA lenticulostrate/lacunar occlusion
pure motor
pure sensory
sensorimotor
presentation of distal MCA occlusion
superior division
-contralateral face and arm weakness and expressive aphasia (Broca’s and PMC)
inferior division
-contralateral face and arm sensory loss. receptive aphasia and homonymous hemianopia (wernickes, PSC and both optic radiations)
presentation posterior cerebral artery
contralateral homonymous hemianopia with macular sparing (due to collateral MCA supply)
contralateral sensory loss due to thalamus damage
symptoms cerebellar infarcts
vomiting, nausea, headaches, vertigo,
DANISH (ipsilateral cerebrellar signs),
ipsilateral brainstem signs as cerebellar arteries supply brainstem as they loop around the cerebellum.
contralateral sensory deficit/ipsilateral corners
presentation brainstem strokes
contralateral limb weakness with ipsilateral cranial nerve signs du to damage to corticospinal tracts above desiccation of pyramids, and damage to cranial nerve nuclei on dame side
presentation of distal basilar artery occlusion
-sudden death as supplies brainstem
distal
- visual and oculomotor deficits
- behavioural abnormalities
- somnolence, hallucinations and dream like behaviour
- motor dysfunction absent
presentation of proximal basilar artery occlusion
at level of pontine branches
- locked in syndrome
- eyes can still move as midbrain still has PCA supply
what are the 4 things on the Oxford stroke classification
PACS, TACS, POCS, LACS
PACS
PARTIAL ANTERIOR CIRCULATION STROKE
2 OF: unilateral weakness of face arm and leg, homonymous hemianopia, dysphasia/aphasia or visuospatial disorder
TACS
TOTAL ANTERIOR CIRCULATORY STROKE
unilateral weakness of face arm and leg, homonymous hemianopia, dysphasia/aphasia or visuospatial disorder
LACS
LACUNAR STROKE/LENTICULOSTRIATE
- pure sensory deficit
- pure motor deficit
- senori-motor deficit
- ataxic hemiparesis
POCS
POSTERIOR CIRCULATION STROKE- one of
- cranial nerve palsy and contralateral motor/sensory deficit
- bilateral motor/sensory deficit
- conjugate eye movement disorder
- cerebellar dysfunction
- isolated homonymous hemianopia with macula sparing
what is the key sign for brainstem pathology
ipsilateral cranial nerve signs and contralateral sensory and motor tract deficits
