Head CT

Question 0

Went to do CT scan if patient has suspected meningitis?

Answer 0

Any signs of focal deficit (hemiparesis etc)

Question 1

Differential for hyperacute thunderclap headache?

Answer 1

#Aneurysmal subarachnoid hemorrhage
#Meningitis
#Reversible cerebral vasoconstriction syndrome
#Pituitary apoplexy
#idiopathic thunderclap headache

Question 2

Patient has signs of dementia. Imaging?

Answer 2

MRI (not CT) to look for atrophy patterns

Question 3

Imaging if patient has initial seizure?

Answer 3

MRI – not CT (better for finding small lesions)

Question 4

CT findings in subarachnoid hemorrhage?

Answer 4

Blood seen in sulci and often in sylvian fissure

Question 5

Causes of intraparenchymal hemorrhage?

Answer 5

#Hypertension
#Amyloid angiopathy
#Metastases
#Vascular malformations

Question 6

Hypodense lesions on head CT suggest?

Answer 6

#Vasogenic edema – swelling due to mass lesions
#Cytotoxic edema – cell death in the setting of stroke

Question 7

Features of vasogenic edema?

Answer 7

#Starts in white matter
#spares cortical ribbon – creates serrated edge effect
#Surrounds tumor, abscess, hemorrhage

Question 8

Features of cytotoxic edema?

Answer 8

#Involves gray and white matter equally
#Has discrete borders
#Usually caused by ischemia (follows Vascular territories)

Question 9

Three things to look for in CT scan?

Answer 9

1. Symmetry
2. Space around the brainstem (perimesencephalic cistern)
3. Ventricle size

Question 10

Patient has no perimesencephalic cistern – Ddx?

Answer 10

#Uncal herniation
#Diffuse cerebral edema

Question 11

Communicating versus noncommunicating hydrocephalus?

Answer 11

Large ventricles WITHOUT obstruction versus large ventricles WITH obstruction of CSF

Question 12

Hydrocephalus ex-Vacuo?

Answer 12

Cerebral atrophy which increases size of all fluid spaces (big sulci and big ventricles)