Neuroradiology Flashcards
What is a complication of administering gadlonium as a contrast agent in patient with renal dysfunction?
Nephrogenic systemic fibrosis
Hyper/hypodense are used to describe features in which imaging modality?
CT
Signal intensities are used in which imaging modality?
MRI
T1 white matter white, grey matter grey
T2 bright CSF but fat also (WW2 water is white in T2)
Which contrast is used in CT?
iodine
Which contrast is used in MRI?
gadolinium
Which imaging is used to ID penumbra?
CT perfusion
Patient is outwith 4.5hr for thrombolysis but has identified a penumbra region on CT perfusion scan. What should you do?
thrombolysis- the timing of the window is not absolute. If patient was <4.5 hr but has no penumbra then you wouldn’t thrombolyse due to concern over haemorrhagic transformation
What are the two types of haemorrhagic transformation?
petechial haemorrhage
intraparenchymal haemorrhage
Which haemorrhagic transformation has worse prognosis?
intraprenchymal haemorrhage
One risk factor for haemorrhagic transformation?
thrombolytic therapy
anticoagulant therapy
80 year old man with hyperdense region in thalamus and has history of HTN presents with confusion and right sided weakness. What do you do?
monitor in ward (there would be an underlying potentially serious cause in a younger patient)
40 year old with hyperdense region in parenchyma indicative of atraumatic intracranial haemorrhage. What is a primary cause?
HTN/CAA= Cerebral amyloid angiopathy
40 year old with hyperdense region in parenchyma indicative of atraumatic intracranial haemorrhage. List two secondary causes of this
coagulopathy vasc malformation tumour recreational drugs vasculitis (therefore need to investigate underlying cause in a younger patient)
What is the difference between haemorrhage caused by HTN and CAA on imaging
haemosiderin distribution is more central in HTN and peripheral in CAA
What is the shape of extradural haemorrhage on CT scan?
bi-convex/lentiform shape
What is the swirl sign?
non-contrast CT appearance of acute extravasation of blood into a haematoma, for example an intracerebral haemorrhage, extradural haematoma or subdural haematoma. It represents unclotted fresh blood which is of lower attenuation than the clotted blood which surrounds it
What is the main type of aneurysm that causes SAH?
saccular
Name two types of anuerysms that cause SAH
saccular (majority), fusiform, dissecting
Where do lesions appear in MS?
periventricular
spinal cord
infratentorial
juxtacortical
Which criteria is used in MS?
MacDonald’s
What is the most common cause of encephalitis?
herpes simplex virus I (HSC1)
What is the treatment of viral encephalitis?
aciclovir, therefore suspiscion of viral encephalitis, treat with aciclovir right away before imaging
Name one change seen typically in brain scan of alzheimer’s disease patient
hypoperfusion in parietal lobe
loss of volume in mediotemporal lobes