Random from Q book

Question 1

pixel size

zoom

matrix

FOV

FWHM

Answer 1

pixel size = FOV/Matrix

matrix = zoom factor x number of pixels across

For spatial resolution, pixel size should be less than 1/3 of FWHM

Question 2

Radiation limit table

Answer 2

Question 3

MRI solutions for motion

Answer 3

Sat bands over offending things

Radial acquisitions

Flip phase and freq directions

Question 4

Best way to reduce ‘magic angle’

Answer 4

Increase echo time

Question 5

what number is magic angle with respect to main field?

Answer 5

55 degrees

Question 6

TR, TE and SNR

Answer 6

Relaxation is bad for SNR, reduce signal strength

So highest SNR would be LONG TR and SHORT TE

(PD IS HIGH SNR)

Question 7

SAR factors

Directly related to

indirectly related to

Answer 7

Increases with field strength and flip angle

DECREASES WITH INCREASED TR

Question 8

Patient codes in MRI

Answer 8

take outside 5 Gauss line

Question 9

what most directly affects contrast in an Inversion Recovery sequence

Answer 9

T1

Question 10

paramagnetic substances shorten what?

Answer 10

T1, T2 and T2*

Question 11

Dark blood =

Bright blood =

Answer 11

DARK SPIN

BRIGHT GRADIENT