Neuroradiology 1 Flashcards
Why would you not perform a lumbar puncture after identifying a subarachnoid haemorrhage on CT?
Don’t want to advance coning
After a CT brain has identified a subarachnoid haemorrhage, what is the next radiological test performed?
Cerebral CT angiogram > digital subtraction angiogram (DSA) as part of management of any identified aneurysm
What are the possible complications of a subarachnoid haemorrhage?
Vasospasm > infarction
Hydrocephalus
Intracerebral haemorrhage
Death
What are the differential diagnoses for sudden onset hemiparesis?
Ischaemic stroke Haemorrhagic stroke TIA Severe migraine Subdural bleeding into tumour
What is the difference between a stroke and a transient ischaemic attack?
Stroke = neurological deficit of vascular origin for >24 hours TIA = neurological deficit of vascular origin for <24 hours
How long does it take for infarcts to be visible on CT brain?
3-4 hours
Most visible within 24 hours
What are the early signs of infarction on CT brain?
Non-contrast CT may be normal in 1st 6 hours after symptom onset
Loss of grey and white matter differentiation
Hypodensity within involved cortex
Sulcal effacement in arterial vascular territory distribution
What other imaging may confirm the diagnosis of cerebral infarction?
Diffusion weighted imaging (DWI) of MRI
Apparent within mins of acute infarction
What is the commonest cause of stroke and transient ischaemic attacks?
Emboli from atheroma of carotid arteries/heart
What are the CSF density structures in the middle cranial fossae?
Temporal horns of the lateral ventricles
If the temporal horns of the lateral ventricles are enlarged, what complication is present?
Aqueduct/4th ventricular outlet compression > obstructive hydrocephalus
What are the differential diagnoses for sudden onset of
- Ataxia
- Dysarthria
- Decreasing level of consciousness
Infarct/haemorrhage in brainstem/cerebellum
Hypoglycaemia
Electrolyte imbalance
What are the differential diagnoses for new onset tingling and paraesthesia in one arm?
MS Cerebral ischaemia Space occupying lesion Spinal cord compression Peripheral nerve impingement Other demyelination disorders Migraine
Why is an active plaque enhanced on T1 MRI, compared to an old plaque?
In active plaque, BBB broken down > enhanced
Over time, gliosis > BBB restored
