Basic Cranial CT

Question 1

Views in skull x rays

Answer 1

Straight PA
Caldwells PA
Grangers
Waters
Towne lateral

Question 2

CT Scan values of clotted blood

Answer 2

+ 100

Question 3

CT Scan values of bones

Answer 3

+ 1000

Question 4

CT Scan values of unclotted blood

Answer 4

+60

Question 5

CT Scan values of brain

Answer 5

+ 24-40

Question 6

CT Scan values of CSF

Answer 6

+5

Question 7

CT Scan values of water

Answer 7

0

Question 8

CT Scan values of fat

Answer 8

-100

Question 9

CT Scan values of air

Answer 9

• 1000

Question 10

A T2 sequence, the normal fluid is suppressed only pathologic fluid remains

Answer 10

FLAIR

Question 11

Imaging modality of choice for hyperacute stroke

Answer 11

DWI and ADC

Question 12

Usually hyperacute stroke can only be seen after how many hours in CT scan?

Answer 12

6 hours

Question 13

How many hours does MRI detects hyperacute stroke?

Answer 13

1-2 hrs.

Question 14

Structures that are mostly affected by infarct (large distribution infarct)

Answer 14

Cortical and subcortical areas

Question 15

What type of infarct is this?

• hyperdense vessel on NECT
• loss of gray-white matter distinction in 1st 3 hrs.
• parenchymal density on NECT

Answer 15

Acute

Question 16

Best diagnostic clue in subacute infarct

Answer 16

Gyral edema and enhancement, occasional with hemorrhagic transformation within basal ganglia, cortex

Question 17

Imaging modality of choice for early infarcts

Answer 17

MRI

Question 18

Extensive hypodense in white matter, usually associated with?

Answer 18

• diventricular and deep white matter ischemic changes
• neurodegenerative disease
• white matter disease (demyelinating disease)

Question 19

Blood supply of parasaggital portion of frontal lobe

Answer 19

Anterior cerebral artery

Question 20

Percentage of population with complete circle of willis

Answer 20

25%

Question 21

4 extra axial locations in intracerebral hemorrhages

Answer 21

• parenchymal
• epidural
• subdural
• subarachnoid

Question 22

Best diagnostic clue in parenchymal hemorrhage

Answer 22

Acute intracerebral hematoma without history of trauma

Question 23

Etiology of parenchymal hemorrhage in elderly patients

Answer 23

Hypertension
Cerebral amyloid angiopathy
Neoplasm
Coagulopathy
Venous occlusion
Cerebral vascular malformation

Question 24

Etiology of parenchymal hemorrhage in younger patients

Answer 24

Drug use
Vasculitis
Venous thrombosis
Cerebral vascular malformation

Question 25

Most spontaneous hemorrhages caused by _?

Answer 25

Hypertension

Question 26

Basal ganglia/ external capsule hematoma are common is patients with?

Answer 26

Hypertension

Question 27

Lobar/ subcortical hematoma is caused by?

Answer 27

Cerebral amyloid angiopathy Cerebral vascular malformation Venous occlusion

Question 28

Give the following percentage distribution of hypertensive hemorrhage

Answer 28

``` Putamen/ external capsule: 60-65% Thalamus: 15-25% Pons: 5-10% Cerebellum: 2-5% Subcortical white matter: 1-2% ```

Question 29

Arteries or vessels in lacunar infarcts

Answer 29

Reticulostriate artery | Thalamostriate artery

Question 30

Best diagnostic clue in epidural hematoma

Answer 30

Hyperdense biconvex extra axial mass on NECT acute phase

Question 31

Best diagnostic clue in subdural hemorrhages

Answer 31

Crescent-shaped, homogenously hyperdense CT, extra-axial collection that spreads diffusely over affected hemisphere

Question 32

Cause of epidural hemorrhage

Answer 32

Rupture of middle meningeal artery

Question 33

Cause of subdural hemorrhage

Answer 33

Tearing of bridging vein

Question 34

Cresentic, crosses the sutures but not dural attachments

Answer 34

Subdural hemorrhage

Question 35

Biconvex or lentiform, crosses the dural attachments but not the sutures

Answer 35

Epidural hemorrhage

Question 36

Subdural or epidural? Has higher mortality

Answer 36

Subdural

Question 37

Most common cause of subdural hemorrhage

Answer 37

Trauma

Question 38

2nd most common cause of subdural hemorrhage

Answer 38

Ruptured aneurysm

Question 39

Preferred modality for trauma

Answer 39

CT scan

Question 40

What are the supratentorial tumors

Answer 40

``` Glioma Meningioma Oligodendroglioma Lymphoma Meningioma Tumors in sellar/parasellar (pituitaru adenoma- most common) ```

Question 41

Give the infeatentorial tumors

Answer 41

``` Schwannoma Meningioma Epidermoid tumors Hemangioblastoma Brainstem glioma Metastasis ```

Question 42

Most common intra axial posterior fossa tumor in adults

Answer 42

Metastatic tumor

Question 43

Butterfly appearance

Answer 43

Gliomablastoma

Question 44

Most common extra axial neoplasm of adults

Answer 44

Meningioma