Week 4 Quiz Flashcards
The area that is bright on the DWI and dark on the ADC map indicates:
a. multiple sclerosis
b. neoplasm
c. Alzheimer’s
d. stroke
d. stroke
due to the restricted diffusion, where water becomes trapped inside cells.
Which feature is only present on the thoracic vertebrae?
a. transverse process
b. vertebral foramen
c. lamina
d. costal facets
d. costal facets
they serve as articulation points for ribs
Negligence is defined as:
A. A legal or civil wrong committed by one person against the person or property of another
B. An obligation not to inflict harm intentionally
C. Professional misconduct, improper discharge of professional duties, or a failure to meet the standard of care by a professional that results in harm to another
D. A failure to exercise the appropriate/reasonable level of care expected to be exercised by professionals in a given circumstance
D. A failure to exercise the appropriate/reasonable level of care expected to be exercised by professionals in a given circumstance
The normal rate of respirations for an adult is:
a. 4-6 breaths per minute
b. 8-12 breaths per minute
c. 12-20 breaths per minute
d. 20-30 breaths per minute
c. 12-20 breaths per minute
The abbreviation “HIPAA” stands for:
Select one:
a. Health Information Protection and Accessibility Act
b. Health Insurance Portability and Accountability Act
c. Health Insurance Protection and Accessibility Act
d. Heart Information Protection and Accountability Act
b. Health Insurance Portability and Accountability Act
To double the flip angle, a ______________ in RF power is required.
Select one:
a. 10% increase
b. no change
c. four-fold increase
d. 2 fold increase
c. four-fold increase
The MR signal is produced by magnetization _________________.
Select one:
a. in the longitudinal direction
b. in the transverse plane
c. out of phase
d. decaying
b. in the transverse plane
At any given time in the magnetic field, there will be a slight majority of proton spins in ___________.
Select one:
a. the neutral state
b. the low energy state
c. enhanced state
d. the high-energy state
b. the low energy state
less protons occupy the high-energy state because it requires more energy to oppose B0
In a spin echo sequence, the time between the middle of the 90-degree pulse and the middle of the 180-degree pulse is ___________.
Select one:
a. TI
b. TE
c. TAU
d. TR
c. TAU
TAU = 1/2 TE, where TE is the time from the 90 RF pulse to the peak of the SE signal
During systole, blood flows in the normal antegrade direction. During diastole, however, pressure in the vessel is reduced, and the blood flows backward (retrograde).
Select one:
a. Laminar flow
b. Vortex flow
c. Triphasic flow
d. Turbulent flow
c. triphasic flow
high-resistance arteries, like peripheral arteries.
3 phases of triphasic flow
- systole
- early diastole
- late diastole
systole
blood moves forward (antegrade) due to ventricular contraction
early diastole
blood momentarily reverses (retrograde) due to elastic recoil and reduced pressure
late diastole
forward flow resumes due to vascular compliance and recoil
What best describes laminar flow?
a. Smooth, parallel layers
b. Chaotic movement
c. Flow reversal
d. Swirling pattern
a. smooth, parallel layers
Vortex flow is:
a. Smooth and steady
b. A swirling pattern
c. Completely random
d. Found only in veins
b. a swirling pattern
Turbulent flow is common in:
a. Normal veins
b. Narrowed vessels
c. Capillaries
d. Large arteries only
b. narrowed vessels
Which is TRUE about turbulent flow?
a. Occurs with high velocity
b. Always present in veins
c. Same as laminar flow
d. Found only in small vessels
a. Occurs with high velocity
Contrast-to-noise ratio is:
Select one:
a. how bright the image is
b. the difference in the SNR between two adjacent areas
c. a measurement of the effectiveness of gating
d. the difference between T1, T2, and proton density times
b. the difference in the SNR between two adjacent areas
Which of the following statements about spatial resolution are correct?
Select one:
a. increasing the FOV increases resolution
b. increasing the slice thickness increases resolution
c. increasing the matrix increases resolution
d. a & c
e. none of the above
c. increasing the matrix increases resolution
The formula for determining precessional frequency is:
Select one:
a. NEX x TR x # phase encoding steps
b. B0 *Y= W0
c. V=IR
d. SNR = SI/SD
b. B0 *Y= W0
What positioning landmark is associated with the level of C4?
Select one:
a. Vertebral prominens
b. Sternal notch
c. Thyroid cartilage
d. Glabella
c. Thyroid cartilage
Narrowing the receive bandwidth of the sequence results in:
Select one:
a. increased SNR
b. decreased SNR
c. decreased chemical shift artifact
d. all of the above
a. increased SNR
The top portion of k-space is a mirror image of the _________________.
Select one:
a. bottom
b. right side
c. top
d. left side
a. bottom
The Technologist should center at the ____________ when imaging the brain.
Select one:
a. Nose
b. Glabella
c. Chin
d. AML
b. glabella
The flip angle that produces the maximum signal for a given tissue at a given TR is known as the ____________.
Select one:
a. 90° flip angle
b. 180° flip angle
c. Fourier angle
d. Ernst angle
d. Ernst angle
If a phase resolution of 256 is desired, then the TR must be repeated ___________ times (for 1 NSA).
Select one:
a. 256
b. 512
c. 192
d. twice
a. 256
phase resolution determines how many times TR must be repeated for a given NSA
____________ minimizes cardiac motion by acquiring images only when the heart is at rest during mid-diastole.
a. Respiratory gating
b. Prospective gating
c. Retrospective gating
d. Peripheral gating
b. Prospective gating
What is the primary function of respiratory gating in MRI?
a. To synchronize image acquisition with the patient’s breathing cycle
b. To minimize cardiac motion artifacts
c. To enhance contrast in images
d. To reduce noise in the imaging process
a. To synchronize image acquisition with the patient’s breathing cycle
Retrospective gating in MRI allows for:
a. Acquiring images only during the most stable part of the cardiac cycle
b. Acquiring data throughout the cardiac cycle and selecting the best images afterward
c. Synchronizing the MRI scan with respiratory phases
d. Minimizing motion artifacts caused by the limbs
b. Acquiring data throughout the cardiac cycle and selecting the best images afterward
Peripheral gating is typically used to synchronize MRI with:
a. Cardiac cycles
b. Respiratory cycles
c. Limb movements or peripheral body part motion
d. Brain activity
c. Limb movements or peripheral body part motion
Which of the following statements is true about gadolinium in its refined state?
A) It is a non-magnetic element.
B) It has paired electrons that cancel out.
C) It is a paramagnetic substance with unpaired electrons.
D) It only exhibits ferromagnetic properties at temperatures above 200°C.
C) It is a paramagnetic substance with unpaired electrons
What is the primary characteristic of gadolinium that makes it paramagnetic?
A) It has paired electrons that cancel out.
B) It has 7 unpaired electrons in its outermost shell.
C) It is made from a rare earth metal.
D) It is ferromagnetic at human body temperature.
B) It has 7 unpaired electrons in its outermost shell.
What is the effect of gadolinium on T1 and T2 relaxation times of tissue?
A) It shortens only T1 relaxation time.
B) It shortens both T1 and T2 relaxation times of tissue.
C) It lengthens both T1 and T2 relaxation times.
D) It has no effect on relaxation times.
B) It shortens both T1 and T2 relaxation times of tissue.
Why does gadolinium have a large magnetic moment?
A) Because it has paired electrons in its outermost shell.
B) Due to its rapid molecular tumbling in solution at Larmor frequency.
C) Because it is a non-ferromagnetic substance.
D) Due to its low relaxation rates.
B) Due to its rapid molecular tumbling in solution at Larmor frequency.
Which relaxation time does gadolinium predominantly affect in tissues?
A) T2 relaxation time.
B) T1 relaxation time.
C) Both T1 and T2 relaxation times equally.
D) None of the above.
B) T1 relaxation time.
What is the primary function of a chelating agent in reducing toxicity?
A. To increase the absorption of toxic metals in the body
B. To bind to toxic metal ions and facilitate their removal from the body
C. To neutralize the effects of toxic metals without removing them
D. To block the entrance of toxic metals into the bloodstream
B. To bind to toxic metal ions and facilitate their removal from the body
Which of the following symptoms or reactions typically resolves without specific treatment after the administration of contrast medium?
A. Anaphylactic-like reaction
B. Headache, nausea, and dizziness
C. Contrast extravasation
D. Urticarial skin rashes
B. Headache, nausea, and dizziness
Which of the following contrast agents is associated with a much lower chance of causing Nephrogenic Systemic Fibrosis (NSF), especially in patients with poor kidney function?
A. Gadavist
B. Magnevist
C. Omniscan
D. Visipaque
A. Gadavist
Which of the following is one of the main functions of the blood-brain barrier (BBB)?
A. To allow unrestricted flow of nutrients to the brain
B. To protect the brain from harmful substances circulating in the blood
C. To enhance the flow of waste products from the brain to the blood
D. To regulate blood pressure in the brain
B. To protect the brain from harmful substances circulating in the blood
Which of the following structures are NOT protected by the blood-brain barrier (BBB)?
A. Pituitary gland
B. Choroid Plexus
C. Hypothalamus
D. Pineal Gland
A, B, and D
Which of the following is the most severe adverse reaction to contrast agents?
A. Hives
B. Respiratory distress
C. Anaphylactic shock
D. Mild nausea
C. Anaphylactic shock
