ARRT MRI exam review 2025 COMPLETE EXAM QUESTIONS AND
ARRT MRI exam review
VERIFIED ANSWERS| 100% ACCURATE SOLUTIONS|ALREADY
Study online at https://quizlet.com/_hbpvp0
GRADED A+
1. what is the most abun- hydrogen
dant element in the hu-
man body?
2. nuclei that are available net spin
for MRI are those that ex-
hibit a _________
3. low energy = spin up = parallel
_______
4. high energy = spin down antiparallel
= __________
5. thermal equilibrium when the body is in the magnetic field, spins are aligned, and nothing
else has happened
6. B0 refers to large magnetic field of the MRI scanner
7. at thermal equilibrium greater
there are a ________
portion of spins with
their magnetic moments
aligned in the same direc-
tion as B0 than against it
8. the reason why SNR in- the NMV also increases in size the stronger B0
creases at higher field
strengths is because
9. 1 hertz = 1 cycle per second
10. larmour equation W0 = y x B0
, ARRT MRI exam review
Study online at https://quizlet.com/_hbpvp0
11. what do the parts of the W0 = Larmour frequency (precessional frequency)
larmor equation mean?
y = gyromagnetic ratio (42.58 MHz/T for hydrogen)
B0 = Field strength
12. what is the precessional 63.87 MHz
frequency for hydrogen (42.58 MHz/T x 1.5T)
at 1.5T?
13. out of phase or incoher- magnetic moments of hydrogen are at different places on the preces-
ent sional path at a moment in time
14. in phase or coherent magnetic moments of hydrogen are at the same place on the preces-
sional path at a moment in time
15. what two things do you 1) coherent
need to get signal? 2) transverse magnetization
16. phase refers to the position of a magnetic moment of a spin on its precessional path
at any moment in time
17. B1 field is used to deliver causes 1) transverse magnetization
an RF pulse which does and 2) phase precession
what 2 things
18. an RF excitation pulse resonance
causes
19. transverse magnetiza- 90
tion occurs at __ degrees
to B0
20. saturation occurs when
, ARRT MRI exam review
Study online at https://quizlet.com/_hbpvp0
spins are unable to absorb more energy or to be stimulated and
release more energy
21. what is a saturation pulse 180 degree RF
22. dephasing and relaxation independent of eachother
happen at the same time
but are
23. relaxation the process in which hydrogen lose energy (occurs after RF excitation
pulse is switched off)
24. dephasing is caused by field inhomogeneities in the B0 field and interactions between spins
and tissue
25. why is it called FID (free spins FREEly precess influenced only by B0, signal DECAYs with time,
induction decay) and magnetic moments of the spins INDUCE a current in receiver coil
26. when RF excitation pulse dephase and produce a FID
is removed, the mag mo-
ments of all spins ____
and ______
27. TR (repetition time) time from application of one RF excitation pulse to the application of
the next one
determines how much longitudinal relaxation occurs (T1 weighting)
28. TE (echo time) time from application of RF excitation pulse to the peak of the signal
induced in the receiver coil
determines how much decay of transverse magnetization occurs (T2
weighting)
, ARRT MRI exam review
Study online at https://quizlet.com/_hbpvp0
29. TR controls how much T1 relaxation occurs, recovery of longitudinal magnetiza-
tion
30. TE controls how much T2 decay occurs, decaying signal of transverse magnetiza-
tion
31. give examples of intrin- - T1 recovery time
sic contrast parameters - T2 decay time
(things that cannot be - Proton density
changed because they - Flow
are inherent to body's tis- - Apparent diffusion coefficient
sues)
32. give examples of ex- - TR
trinsic contrast parame- - TE
ters (those that can be - Flip angle
changed because they - TI
are under our control) - turbo factor (ETL)
- b value
33. describe the process of - B1 field is turned off
relaxation - hydrogen nuclei return to their low-energy state
- magnetic moments dephase
- NMV returns to B0
34. relaxation therefore re- recovery and decay
sults in the _______ lon-
gitudinal magnetization
and the _____ of trans-
verse magnetization
35. which is faster decay or decay
recovery?
ARRT MRI exam review
VERIFIED ANSWERS| 100% ACCURATE SOLUTIONS|ALREADY
Study online at https://quizlet.com/_hbpvp0
GRADED A+
1. what is the most abun- hydrogen
dant element in the hu-
man body?
2. nuclei that are available net spin
for MRI are those that ex-
hibit a _________
3. low energy = spin up = parallel
_______
4. high energy = spin down antiparallel
= __________
5. thermal equilibrium when the body is in the magnetic field, spins are aligned, and nothing
else has happened
6. B0 refers to large magnetic field of the MRI scanner
7. at thermal equilibrium greater
there are a ________
portion of spins with
their magnetic moments
aligned in the same direc-
tion as B0 than against it
8. the reason why SNR in- the NMV also increases in size the stronger B0
creases at higher field
strengths is because
9. 1 hertz = 1 cycle per second
10. larmour equation W0 = y x B0
, ARRT MRI exam review
Study online at https://quizlet.com/_hbpvp0
11. what do the parts of the W0 = Larmour frequency (precessional frequency)
larmor equation mean?
y = gyromagnetic ratio (42.58 MHz/T for hydrogen)
B0 = Field strength
12. what is the precessional 63.87 MHz
frequency for hydrogen (42.58 MHz/T x 1.5T)
at 1.5T?
13. out of phase or incoher- magnetic moments of hydrogen are at different places on the preces-
ent sional path at a moment in time
14. in phase or coherent magnetic moments of hydrogen are at the same place on the preces-
sional path at a moment in time
15. what two things do you 1) coherent
need to get signal? 2) transverse magnetization
16. phase refers to the position of a magnetic moment of a spin on its precessional path
at any moment in time
17. B1 field is used to deliver causes 1) transverse magnetization
an RF pulse which does and 2) phase precession
what 2 things
18. an RF excitation pulse resonance
causes
19. transverse magnetiza- 90
tion occurs at __ degrees
to B0
20. saturation occurs when
, ARRT MRI exam review
Study online at https://quizlet.com/_hbpvp0
spins are unable to absorb more energy or to be stimulated and
release more energy
21. what is a saturation pulse 180 degree RF
22. dephasing and relaxation independent of eachother
happen at the same time
but are
23. relaxation the process in which hydrogen lose energy (occurs after RF excitation
pulse is switched off)
24. dephasing is caused by field inhomogeneities in the B0 field and interactions between spins
and tissue
25. why is it called FID (free spins FREEly precess influenced only by B0, signal DECAYs with time,
induction decay) and magnetic moments of the spins INDUCE a current in receiver coil
26. when RF excitation pulse dephase and produce a FID
is removed, the mag mo-
ments of all spins ____
and ______
27. TR (repetition time) time from application of one RF excitation pulse to the application of
the next one
determines how much longitudinal relaxation occurs (T1 weighting)
28. TE (echo time) time from application of RF excitation pulse to the peak of the signal
induced in the receiver coil
determines how much decay of transverse magnetization occurs (T2
weighting)
, ARRT MRI exam review
Study online at https://quizlet.com/_hbpvp0
29. TR controls how much T1 relaxation occurs, recovery of longitudinal magnetiza-
tion
30. TE controls how much T2 decay occurs, decaying signal of transverse magnetiza-
tion
31. give examples of intrin- - T1 recovery time
sic contrast parameters - T2 decay time
(things that cannot be - Proton density
changed because they - Flow
are inherent to body's tis- - Apparent diffusion coefficient
sues)
32. give examples of ex- - TR
trinsic contrast parame- - TE
ters (those that can be - Flip angle
changed because they - TI
are under our control) - turbo factor (ETL)
- b value
33. describe the process of - B1 field is turned off
relaxation - hydrogen nuclei return to their low-energy state
- magnetic moments dephase
- NMV returns to B0
34. relaxation therefore re- recovery and decay
sults in the _______ lon-
gitudinal magnetization
and the _____ of trans-
verse magnetization
35. which is faster decay or decay
recovery?
