10.1.2 Brainstem and Cerebellar Strokes Flashcards
What happens in a PCA occlusion?
Somatosensory and visual dysfunction is typical
Contralateral homonymous hemianopa (macular sparing due to collateral supply from MCA)
Contralateral sensory loss due to thalamus damage
What are the symptoms of cerebellar infarcts?
Nausea
Vomiting
Headache
Vertigo/dizziness
What are the signs of cerebellar infarcts?
Ipsilateral cerebellar, DANISH
Ipsilateral brainstem affected as cerebellar arteries supply brainstem as they loop round to the cerebellum
Ipsilateral Horner’s- brainstem involvement
What is a typical feature of brainstem strokes?
Contralateral limb weakness with ipsilateral cranial nerve signs
Due to damage to corticospinal tracts (above decussation of pyramids) and damage to cranial nerve nuclei on same side
What can happen in a basilar artery occlusion?
Supplies the brainstem, can cause sudden death
What happens in distal basilar artery occlusion?
- Visual and oculomotor deficits
- Behavioural abnormalities
- Somnolence, hallucinations and dreamlike behaviour (brainstem has important sleep regulation centres)
- Motor dysfunction is absent
Why do you get visual and oculomotor deficits in distal basilar artery occlusions?
Basilar sends some branches to midbrain which has oculomotor nuclei
Occlusion at the site can prevent blood flowing into PCAs affecting ocipital lobes
Why is motor dysfunction often absent in occlusion of distal basilar artery?
Cerebral peduncles can get blood from the PCAs which are being filled by posterior communicating arteries
Where do proximal basilar occlusions occur?
Level of pontine branches
What causes proximal basilar occlusions?
Emboli in basilar arteries
Can occlude pointine branches on each side
What does proximal basilar occlusion lead to?
Locked in syndrome
Complete loss of movement of limbs
Presserved ocular movement
Preserved consciousness
Why are the eyes still able to move in proximal basilar artery occlusions?
Midbrain still getting supply from PCAs via posterior communicating arteries
Why is consciousness preserved in basilar artery occlusion?
Midbrain reticular formation still intact
What clinical tool can be used to quickly diagnose strokes?
Bamford (oxford) stroke classification
Complete the table
What type of OSCP term causes this CT and MRI?
Total Anterior Circulation Syndrome
What type of OSCP term causes this CT and MRI?
Partial Anterior Circulation Syndrome
What type of OSCP term causes this CT and MRI?
Posterior Circulation Syndrome
What type of OSCP term causes this CT and MRI?
Lacunar Syndrome
