Chapter 6 - Relaxation Time & Spin Density Quiz

Which of the following is not a principle MRI parameter?
A. Larmor equation
B. spin density
C. T1 relaxation
D. T2 relaxation

A. Larmor equation

Tissue B has higher density than tissue A.Tissue B will:
A. appear brighter
B. appear darker
C. have longer relaxation times
D. have shorter relaxation times

A. appear brighter

Which of the following tissues, based strictly on spin density should appear brightest?
A. fat
B. water
C. muscle
D. bone

B. water

Which of the following tissues, based strictly on spin density should appear darkest?
A. fat
B. water
C. muscle
D. bone

D. bone

In addition to spin density, signal intensity is also affected by:
A. how the spin is chemically bound
B. how the spin is charged
C. the mass of the spin
D. the distribution of the spin

A. how the spin is chemically bound

Spin density most closely related to:
A. bound hydrogen
B. mobile hydrogen
C. transient hydrogen
D. induced hydrogen

B. mobile hydrogen

Spin density can best be defined as hydrogen:
A. concentration
B. charge
C. relaxation
D. configuration

A. concentration

Spin density can be best described as the number of hydrogen nuclei:
A. passing through the voxel
B. at equilibrium in a voxel
C. excited in a voxel
D. in a voxel

D. in a voxel

Spin density is closest to concentration of nuclei in:
A. bound hydrogen
B. mobile hydrogen
C. tissue
D. water

B. mobile hydrogen

Spin density is most closely related to:
A. precession
B. relaxation
C. induction
D. concentration

D. concentration

Net magnetization at equilibrium (M0)
A. spin density
B. T1 relaxation
C. T2 relaxation
D. precession

A. spin density

Which of the tissues represented in the above figure has highest spin density?
A. A
B. B
C. C
D. not enough information

A. A

The above figure is a graph of?
A. Spin density
B. Spin density relaxation
C. Longitudinal relaxation
D. Transverse relaxation

C. Longitudinal relaxation

The above figure is a graph of?
A. spin density
B. spin density relaxation
C. longitudinal relaxation
D. transverse relaxation

D. transverse relaxation

At equilibrium Mz equals:
A. Mo
B. Mxy
C. spin density
D. relaxation

A. Mo

At equilibrium Mz is undetectable because:
A. it relaxes too fast
B. the spin density is too low
C. Mo is too high
D. Bo is too high

A. it relaxes too fast

T1 relaxation time is also known as:
A. spin density
B. longitudinal relaxation
C. transverse relaxation
D. precession

B. longitudinal relaxation

T1 relaxation occurs:
A. rapidly at first, then slows down
B. is contestant
C. slowly at first, then speeds up
D. is discontinuous

A. rapidly at first, then slows down

T1 relaxation time is related to the time required for:
A. Mz to return to equilibrium
B. Mxy to return to equilibrium
C. transverse saturation
D. longitudinal saturation

A. Mz to return to equilibrium

The T1 relaxation time is 300ms. What will be the value of Mz after a patient has been in a static magnetic field for 300 ms?
A. 0.37 Mz
B. 0.63 Mz
C. 0.37 Mo
D. 0.63 Mo

D. 0.63 Mo

T1 relaxation times are generally:
A. shorter than T2 relaxation times
B. about the same as T2 relaxation times
C. longer than T2 relaxation times
D. vary from tissue to tissues in relation to T2 relaxation times

C. longer than T2 relaxation times

After removal from the magnet for approximately five T1 relaxation times, Mz will equal approximately:
A. 0
B. 0.37 Mo
C. 0.63 Mo
D. Mo

D.M0

Which of the following tissue has the longest T1 relaxation time?
A. fat
B. brain
C. CSF
D. muscle

C. CSF

The time constant for the return of Mz to Mo is:
A. spin density
B. T1 relaxation time
C. T2 relaxation time
D. precessional frequency

B. T1 relaxation time

In general, as B0 increases the T1 relaxation time will:
A. decrease
B. remain the same
C. increase
D. vary from tissue to tissue

C. increase

When Mz equals 0, it takes approximately _ T1 relaxation time to return to equilibrium?
A. 1
B. 3
C. 5
D. 7

C. 5

The term longitudinal, in longitudinal relaxation time refers to events occurring along the axis of the:
A. patient
B. static magnetic field
C. magnetic field gradient
D. radio antennae

B. static magnetic field

Following an RF pulse, Mz will return to Mo, with a relaxation time described as:
A. precessional
B. inductional
C. longitudinal
D. transverse

C. longitudinal

Relaxation in equilibrium represents return to:
A. a lower energy state
B. the same energy state
C. a higher energy state
D. an energy state that is tissue dependent

A. a lower energy state

In the spin lattice relaxation time, lattice refers to:
A. stepping through T1, 2T1, 3T1…..
B. the spin quantum number of hydrogen
C. the electron configuration of hydrogen
D. the molecule in which the hydrogen is bound

D. the molecule in which the hydrogen is bound

During the return to equilibrium, spins give up energy to:
A. other spins
B. electrons
C. the molecules
D. the tissue

C. the molecules

Generally, the appearance of tissue having a short T1 relaxation time on a T1 weighted image will appear:
A. dark
B. gray
C. bright
D. varies with tissue type

C. bright

In general, The T1 relaxation time:
A. is shorter for diseased tissue
B. is longer for diseased tissue
C. remains unchanged for diseased tissue
D. is longer for some disease tissue and shorter for others

D. is longer for some disease tissue and shorter for others

The T1 relaxation time for a given tissue is 400 ms. What will be the value of Mz when a patient has been in a magnet for 800 ms?
A. 0.63 Mz
B. 0.86 Mz
C. 0.63 Mo
D. 0.86 Mo

D. 0.86 Mo

Transverse magnetization is symbolized by:
A. Bo
B. Mo
C. Mxy
D. Mz

C. Mxy

Relaxation of transverse magnetization is controlled by:
A. spin density
B. T1 relaxation
C. T2 relaxation
D. precession

C. T2 relaxation