(neuro) cerebrovascular disorders (tutorial) Flashcards
how does a subdural haemorrhage occur?
shearing of delicate veins causes them to rupture releasing low pressure venous blood into the subdural space
why is a left sided lesion more impactful than a right sided one?
both Broca’s and Wernicke’s areas are found on the left side of the brain - so increased risk of both expressive and receptive aphasia
how do you differentiate between a subdural and an extradural haemorrhage on a CT scan?
extradural = 'lemon' shaped subdural = 'banana' shaped
(onset of symptoms is later/more delayed in a subdural haemorrhage while an extradural haemorrhage present with acute symptoms)
when looking at brain CT scans, what is the key feature to look out for?
asymmetry, which can be seen in the midline
how does the symptom of a headache link to a haemorrhage?
increased intercranial pressure as haemorrhage causes increased pressure on brainstem
how do the symptoms of a weak right arm and leg link to a haemorrhage?
haemorrhage near the left primary motor cortex compressing the region responsible for coordinating movement of the right arm and leg
how does the symptom of a hesitant speech link to a haemorrhage?
haemorrhage near Broca’s area pressurises/compresses it, impairing speech production
how does the symptom of a drowsiness link to a haemorrhage?
reticular activating system in brainstem being compressed due to increased ICP
hypotension due haemorrhage causes syncope
how are brain CT scans studied?
bottom-up orientation as looking at patient from bottom of bed (our right is their left)
how is a subdural haemorrhage treated?
drill burr holes, remove skull flap, remove pooled blood and relieve pressure then reassemble the skull flap
(also decompression surgery)
how can an intracerebellar haemorrhage cause dizziness?
haemorrhage compresses the motor neurones from the cerebellum that are responsible for balance and coordination, impairing them
how can an intracerebellar haemorrhage cause wobbly eye movements?
compression of the oculomotor, abducens and trochlear nerves that originate at the cerebellum due to increased pressure as a result of the haemorrhage
why is it more difficult to operate on an intercerebellar haemorrhage?
more difficult for neurosurgeons to access and approach site of haemorrhage due to presence of other cerebral structures
why is compliance with anti-hypertensive medication low?
usually quite low as patients do not associate missing doses with significant symptoms that affect their daily life
