VERIFIED ANSWERS GRADED A+ FOR
GUARANTEED PASS
◉As the number of phase encodings is increased from 256 to 512, SNR
(signal to noise ratio):
A. Increases
B. Decreases
C. Doubles
D. Does not change
E. Quadruples . Answer: Decreases
◉A magnetic vector possesses attributes of both __________ and
_____________.
A. Strength; magnitude
B. Direction; purpose
C. Strength; flow
D. Magnitude; direction . Answer: Magnitude; direction
◉What element in the body is the principal nucleus utilized in clinical
MR imaging?
,A. Helium
B. Hydrogen
C. Oxygen
D. Calcium . Answer: Hydrogen
◉Which of the following best describes an IR sequence?
A. A 180° pulse followed by a 90°/180° combination
B. A 90° pulse followed by a 180° pulse
C. A train of gradient echoes
D. A train of spin echoes . Answer: A 180° pulse followed by a 90°/180°
combination
◉Gradient echo sequences requiring high signal from fluid are known as
all of the following EXCEPT:
A. T2* gradient echo
B. Steady-state gradient echo
C. Coherent gradient echo
D. Incoherent gradient echo . Answer: Incoherent gradient echo
◉The medial and lateral rectus muscles are located in the:
A. Ears
B. Posterior pelvic region
,C. Proximal calves
D. Eyes
E. Superior shoulder regions
F. Soft tissues of the neck . Answer: Eyes
◉Reducing the number of lines filled in k-space will produce an image:
A. With a decrease in spatial resolution
B. With a increase in spatial resolution
C. With an decrease in overall SNR
D. With an increase in overall SNR
E. With a reduced overall scan time
F. B, C and E only
G. A, D and E only . Answer: A, D and E only
Reducing the number of lines filled in k-space reduces the number of
phase encoding steps, resulting in shorter scan time, an increase in
overall SNR, but a decrease in spatial resolution.
◉The smallest object that can be resolved in an image acquired with a
24cm FOV and a 272 x 272 matrix is _________ mm.
A. 0.76mm
B. 0.88mm
, C. 0.93mm
D. 1.13mm
E. 1.24mm . Answer: 0.88mm
◉To produce an image based on differences in T1, the time interval
between 90° excitation pulses should be:
A. Long
B. Short
C. Refocussed
D. Inverted . Answer: Short
◉The energy used to form MRI images is ____________ the patient's
tissues.
A. Emitted from
B. Attenuated by
C. Amplified from
D. Reflected off . Answer: Emitted from
◉Referencing the Centers for Disease Control and Prevention (CDC),
what type of isolation precautions should be used for HIV-positive
patients in the MRI suite?
A. Respiratory
B. Droplet