Brain Imaging Flashcards
In a T2 weighted MRI scan does water show up bright or dark?
Bright
In a T1 weighted MRI scan does water show up bright or dark?
Dark
In which MRI scan (T1 or T2) is anatomical resolution better?
T1
In which MRI scan (T1 or T2) is pathological tissue highlighted?
T2
On a brain MRI you see that the ventricles show up bright white. Is this a T1 or T2 weighted image?
T2
Describe how you would get a CT angiogram?
CT image during and immediately after pumping in a bolus of iodine contrast
Describe how you would get a CT venogram?
CT image 2.3 seconds after pumping in a bolus of iodine contrast
When would you get iodine contrast showing up in the brain? How would you look for this on a CT?
If the blood brain barrier has been disrupted by tumours or inflammation. CT scan taken 5 minutes after iodine contrast injection.
What test would you want to do in a young women who has suffered from a confirmed spontaneous subarachnoid haemmorhage?
Angiography
What is the gold standard test for imaging blood vessels in the neck and intracranially?
Digital Subtraction angiography
What kind of aneurysm involves all layers of the vessel wall and most commonly arises at arterial bifurcation points?
Saccular aneurysms
What is the first line imagining to do in someone who has presented with a suspected subarachnoid haemorrhage?
CT scan
What is the treatment for a berry aneurysm?
Craniotomy and clipping
Endovascular treatment
Describe the endovascular treatment used in brain aneurysms?
Detachable platinum coils are put into the aneurysm to slow the blood flow in and out and allow thrombosis to occur which will eventually seal the aneurysm
Describe the angiography procedure
Contrast is injected into the aortic arch and into the carotid or vertebral arteries and X rays are taken.
What is the first line imagine technique for a suspected subarachnoid haemmorhage?
Non contrast CT
What colour does blood show up on a CT?
Bright
Why might you get hydrocephalus with a large volume sub arachnoid haemmorhage?
Blood might spread throughout the basal cisterns and extend into the ventricles. This obstructs CSF drainage and can cause hydrocephaul
If you have a confirmed SAH on CT what imaging test would you want to do next?
Cerebral angiogram
If there is strong clinical suspicious of a SAH but the CT looks normal what test would you do?
Lumbar pucture to look for elevated red cell count
Where is a subdural haematoma?
Between the dura and arachnoid
What causes a subdural haemoatoma?
Rupture of the veins that cross this space
Who is most at risk of a subdural haematoma?
Those with cerebral atrophu as the subdural space is larger and the veins are at increased risk of injury.
Where is an extradural haematoma?
Between the skull and the dura
