MRI general stuff

Question 1

Does bone affect MRI

Answer 1

No, it is ‘not affected by bony artefacts’

Question 2

What is Diffusion weighted MRI, and ADC

Answer 2

Diffusion Weighted Images (DWI) and Apparent Diffusion Coefficient images (ADC)

Measures the movement of protons.

The most sensitive method to detect early stroke
Also useable to map white matter tracts.

Areas of high signal on the DWI images and low signal on the ADC images indicate ‘restricted diffusion’ - an indicator of a pathological process of cell death such as infarction, cancer, or abscess formation

Question 3

FLAIR imaging

Answer 3

FLAIR images (Fluid Attenuated Inversion Recovery) are commonly used in brain imaging

The signal from free fluid – such as cerebrospinal fluid (CSF) in the ventricles – is suppressed

High signal indicates a pathological process such as infection, tumour, or areas of demyelination as in MS.

Question 4

STIR MRI image

Answer 4

a T1 weighted image with suppression of the adipose signal. Fat appears dark, and edema which is normally dark is strongly intense.

Shot T1 Inversion Recover.

Question 5

T1 tissue characteristics

Answer 5

CSF/standing water is dark.
Lesions are darker than normal
Adipose is bright

White matter is brighter than Gray matter

flowing blood has no signal

Question 6

T2 tissue characteristics

Answer 6

CSF and water is bright, mad bright.
Adipose is also bright
Lesions are mad bright.

Gray matter is brighter than White matter

flowing blood has no signal.

Question 7

PD weighted image

Answer 7

Proton Density
Good for brain, myelin

Good for joints, because it has good differentiation between hyaline cartilage, fibrocartilage, and fluid.

Question 8

What imaging method is used in fMRI

Answer 8

BOLD
Blood Oxygenation Level Dependent imaging.

Decreased oxygen levels.