Quiz 1 MRI

1.     The superconducting MR scanner contains all of the following except

• Liquid helium

• Liquid nitrogen

• Main magnet coil

•  Superconducting shim coils

2.     Magnetic field gradients for imaging are typically measured in units of

• Millitesla per meter (mT/m)

• Gauss per second (G/s)

• Tesla (T)

• Tesla per meter per second (T/m-s)

3.     In order to perform an MRI experiment, we first need to

• Apply a radiofrequency pulse in a different direction from B0

• Apply a radiofrequency pulse along B0

• Change the strength of B0

• Apply a magnetic field gradient

4.     A spin echo is formed by

• Reversing the direction of B0

• Flipping proton direction by a radiofrequency pulse

• Applying a negative magnetic field gradient

5.     The fast spin echo sequence alters the spin echo sequence by

• Adding successive 90-degree pulses

• Adding successive frequency-encoding gradients

• Adding successive 180-degree pulses

• Adding successive spoiler gradients

6.     Compared with spin echo (SE), the gradient echo (GRE) sequence

• Has a 180-degree pulse and demonstrates T2* dephasing

• Has no 180-degree pulse and demonstrates T2* dephasing

• Has a 180-degree pulse and demonstrates T2 dephasing

• Has no 180-degree pulse and demonstrates T2 dephasing

7.     Compared with SE, GRE sequences use

• Longer TR and longer TE

• Shorter TR and longer TE

• Longer TR and shorter TE

• Shorter TR and shorter TE

8.     How is proton-density weighting achieved?

• Short TR, long TE

• Long TR, short TE

• Short TR, short TE

9.     What color is water in a T1 weighted MRI scan?

• White

• Dark grey

• Black

• Light grey

10.     Increasing TR:

• Decreases T1-weighting

• Increases T1-weighting

• Decreases T2-weighting

• Increases T2-weighting