Brain Flashcards
How does ischemia of the brain present on CT
Loss of the grey/white matter borders
Gets more obvious as time goes on
What test is usually first line for brain imaging
CT without contrast
Fast and well tolerated
How does fluid present differently on a T1 and T2 weighted MRI
T1 - fluid is black
T2 - fluid is white
What colour is CSF on a CT
Black
Which of the arteries supplies most of the brain
Middle cerebral artery
What must be done before you can perform thrombolysis
• Need to exclude haemorrhage in order to safely give thrombolysis
Do an CT of the head to look for haemorrhage
How does a brain haemorrhage present on CT
Acute blood appears as white on an unenhanced CT
Extradural will be lens shaped on CT
Subdural will be moon shaped on CT
Which type of brain haemorrhage will present with a lucid interval before rapidly deteriorating
Extradural haemorrhage
Takes a while for the mass effect
A brain tumour in an adult is most likely to be what
A metastasis
Must follow up with a CT chest, abdomen and pelvis to look for the primary cancer
What is the earliest sign of an ischaemic stroke on CT
A hyperdense (white) segment of the affected vessel This is a visualisation of the thrombus or embolus
Describe the progress of a stroke on imaging (if not treated)
Hyperdense vessels seen as the blockage
Ischaemia presents as loss of grey/white border
Swelling becomes more marked and mass effect occurs
Gliosis eventually appears s a region of low density (black) with volume loss
What usually causes an extradural haemorrhage
Trauma - often has an associated skull fracture
Bleeding is usually from the middle meningeal artery
How does a chronic subdural haematoma present on CT
It is hypodense - darker
What most commonly causes a subdural haemorrhage
Trauma
RTA in younger people
Falls are enough in the elderly
What most commonly causes subarachnoid haemorrhage
most commonly a ruptured berry aneurysms in the circle of willis
