Neuroradiology Advanced Flashcards
Most common causes of stroke
80% cerebral ischemia/infarct
15% intracerebral hemorrhage
5% subarchnoid hemorrhage caused by aneurysm
Best test for subarachnoid hemorrhage
Non-contrast CT… recall CT is very good at picking up acute blood
Most common locations (2 of em) for intracerebral hemorrhages
1) putamen – causes hemiparesis via internal capsule
2) thalamus - causes hemiparalysis
What is a cerebral infarct and what is the best test for it?
infarct = necrotic tissue due to lack of blood supply
Best test is Diffusion-weighted MRI… recall CT is good at seeing bleeds, but an infarct is not a bleed
look for hypodensities in distribution of cerebral vessels (CT won’t show anything for 24 hours)
def. of penumbra
tissue that is at risk of irreversible damage, but is still salvagable
what is an arteriovenous malformation?
an abnormal communicating vessel - typically formed congenitally.
often results in hemorrhage
intra-axial neoplasm
originates within brain parenchyma
75% of the type either a metastasis or astrocytoma
extra-axial neoplasm
originates outside of brain parenchyma (derived from lining etc)
80% of time is either a meningioma or schwannoma
Most common primary malignant brain neoplasm
Glioma (intra-axial)
most common primary benign brain neoplasm
meningioma (extra-axial)
Most common secondary brain neoplasms
metastasis (either intra or extra axial)
You see a mass in the sella turcica, what type of neoplasm is it?
sella turcica would be “extra exial” so it is likely either a meningioma or schwannoma
How does Multiple Sclerosis present on a neuroradiological test, and what is the best test?
T2 MRI with FLAIR is the best because MS typically presents with multiple peri-ventricular lesions… and the FLAIR helps to remove background “noise” from CSF within the ventricles to allow better imaging around them
Location most often impacted by herpes simplex encephalitis
temporal lobe (best seen with MRI)
How does a brain abscess appear in neuroradiology?
**Ring-enhancing lesion (hollow in middle)
hyperintensity ring via MRI with fairly distinct borders
