Flashcards in Workbook - Neuroradiology Deck (45)
What direction are conventional CTs viewed from?
Below, with the patient looking up.
(^ = anterior, > = left,
What sort of images are CTs?
-not truly horizontal
What are the main differences between CT and MRI?
CT: - x-rays (radiation)
-best detail; bone
MRI: -magnetic fields (no radiation)
-contraindications; metal implants
-best detail; soft tissue
When are CTs commonly used for in neuroimaging?
Stroke, tumour, head injury.
When are MRIs most useful?
-pituitary gland & brainstem
What appears bright (AKA hyperdense) on CT?
What appears bright (AKA hyperdense) on T1 weighted MRI?
What appears bright (AKA hyperdense) on T2 weighted MRI?
What appears dark (AKA hypodense) on CT?
What appears dark (AKA hypodense) on T1 weighted MRI?
What appears dark (AKA hypodense) on T2 weighted MRI?
In what type of scan is bone very white?
Which regions of the brain does the anterior cerebral artery supply?
-Medial and upper frontal lobe
-Superior parietal lobe
Which regions of the brain does the middle cerebral artery supply?
-Most of lateral surface (except upper parietal and frontal lobes, and inferior temporal)
Where is Broca's area located?
Lateral inferior frontal lobe.
Where is Wernicke's area located?
Lateral temporal lobe.
Which regions of the brain does the posterior cerebral artery supply?
-Inferior/medial temporal lobe
-Occipital lobe (midbrain & thalamus)
What is TACI?
Total Anterior Circulation Infarct.
-cerebral infarction that affects anterior circulation affecting one side of the brain
>> motor and sensory defects, dysphasia, etc.
What is PACI?
Partial Anterior Circulation Infarct.
-cerebral infarction that affects part of anterior circulation affecting one side of the brain
>> partial motor and sensory defects, dysphasia, etc
What is POCI?
POsterior Circulation Infarct.
-cerebral infarction that affects posterior circulation affecting one side of the brain
>> nerve palsy, bilateral motor and sensory defects, cerebellar dysfunction
What is a lacunar stroke (LACI)?
Stroke due to occlusion of one of the penetrating arteries to the brain's deep structures.
What are the CT findings for a right-sided infarct? (2)
-Loss of grey-white differentiation
-Oedema on right
How will patients with right-sided infarct due to the middle cerebral artery present?
How does acute infarct appear on a CT?
Hyperdense / bright.
How does subacute infarct appear on a CT?
Isodense / grey.
How does chronic infarct appear on a CT?
Hypodense / dark.
What type of scan should be used for imaging the posterior fossa?
What are the anatomical components of the basal ganglia? (3)
-Corpus striatum (caudate & lentiform nuclei)
What is a subarachnoid haemorrhage?
Bleeding into the subarachnoid space.
-spontaneous / due to head injury