Neuroimaging

Question 1

CT Scan Without Contrast

Answer 1

Trauma
R/O stroke
R/O hemorrhage
Hydrocephalus
Dementia
Epilepsy
Congenital malformations

Question 2

CT Scan With Contrast

Answer 2

Neoplasm
Infection
Vascular disease
Inflammatory disease

Question 3

What appears bright or dark on CT

Answer 3

The more dense the tissue, the brighter it looks on CT
Any calcified structure (like the skull) appears bright
New hemorrhage in the brain is also bright
Water (or CSF) looks dark on CT

Question 4

Subarachnoid hemorrhage

Answer 4

Arterial bleeding on the surface of the brain
Between the pia mater and the arachnoid mater
Injury of small arteries or veins on the surface of the brain
Trauma
Ruptured cerebral aneurysm

Question 5

Subdural hematoma

Answer 5

Venous bleeding between the arachnoid and the dura mater
Tearing of bridging veins from deceleration and acceleration or rotational forces
Blood collects in the space between the arachnoid mater and the dura mater
CT has the following characteristics:- Crescent shaped/banana shaped Hyperdense, may contain hypodense foci

Question 6

Epidural hematoma

Answer 6

Dural artery or venous sinus bleeding between the skull and dura
Associated with skull fracture
On CT, the hematoma forms a hyperdense biconvex mass…Lens shaped

Question 7

CT Angiography indications

Answer 7

Atherosclerosis
Thromboembolism
Vascular dissection
Aneurysms
Vascular Malformations
Penetrating trauma
Evaluation of carotids

Question 8

T1 MRI

Answer 8

useful to look at normal anatomy of the brain
Fat is bright
White matter (inner part of brain) is brighter than gray matter (cortex or outer part of the brain)
Water (CSF) is dark

Question 9

T2 MRI

Answer 9

useful to look at abnormal processes (or pathology) in the brain
The difference between T1 and T2 are different pulse sequences
Water is bright
Blood is bright
White matter is darker than gray matter