What is the name of the gradient coil used to produce sagittal and coronal images?
a. Transverse coil
b. Golay coil
c. Maxwell coil
d. Receiver coil -
... [Show More] b. Golay coil ("saddle coil")
Which of the following is able to handle the most RF heating?
a. elderly
b. adult
c. obese adult
d. neonate - d. neonate
Which of the following techniques can be used to increase the echo spacing? Select all that apply.
a. Increase the TR
b. Decrease receiving bandwidth
c. Increase receiving bandwidth
d. Use a receive only coil
e. Increase field of view
f. Increase flip angle - b, e
Decreasing the receiving bandwidth will be lengthening the sample time. This may force us to increase our TE as well as the TR. Increasing the field of view will also allow for longer echo spacing.
The differences in magnetic field strength as you approach the MRI unit is termed what?
a. Spatial magnetic gradient
b. Gauss line
c. RF energy
d. Gradient coils - a. Spatial magnetic gradient
Measured in dB/dx
Which of the following produce the greatest chance for peripheral nerve stimulation?
a. Conventional spin echo
b. Fast spin echo
c. Gradient echo
d. EPI - d. EPI
A deflection of 45 degrees in a tested implant indicates that it deflects at a force equal to what?
a. 0.5 gravity force
b. 2 gravity force
c. 0.25 gravity force
d. 1 gravity force - d. 1 gravity force
4T/m is equal to what?
a. 4000 G/cm
b. 4G/cm
c. 40 G/cm
d. 400 G/cm - d. 400 G/cm
1T = 10,000 G
1m = 100 cm
Therefore, 1 T/m=10,000G/100cm
This means that 1 T/m=100 G/cm
How do we calculate the maximal spatial gradient?
a. dB/dx * B
b. dB/dt * W/kg
c. W/kg
d. B - a. dB/dx * B
What group issued the ACR white paper MRI safety?
a. ACR Blue Ribbon Panel on MR safety
b. FDA
c. OSHA
d. EPA - a. ACR Blue Ribbon Panel on MR safety
Which of the following is true of a gad contrast osmolarity?
a. Less than blood
b. Greater than blood
c. Less than water
d. Equal to blood - b. Greater than blood (and greater than water)
Which of the following is true if we increase the field of view from 200mm to 400mm?
a. We reduce patient heating
b. We use a stronger time-varying gradient magnetic field
c. We use a weak time-varying gradient magnetic field
d. We increase the patient heating - c. We use a weak time-varying magnetic field.
Larger field of views will produce lower resolution exams. The size of the field of view is dependent on the frequency encoding gradient coil. When we increase the field of view, we decrease the amplitude of our gradient coil.
When a T1 weighted image is taken of a vial of gad contrast, it will appear how?
a. Bright
b. Dark
c. Gray
d. Blue - b. Dark
Active shield is performed how?
a. Nothing is used with active shielding
b. A magnetically conductive material surrounds the MR unit and this shapes and contains the magnetic field
c. Bricks of permanent magnets are stacked around the MR unit to contain the fringe field
d. A coil of wire in the MR unit has a current running through it which produces a magnetic field opposing the B0 - d. A coil of wire in the MR unit has a current running through it which produces a magnetic field opposing the B0.
A coil of wire is used with a current of wire running through it to produce a magnetic field. This is placed opposing the vector of the static magnetic field. This will cancel out some of the magnetic field felt outside of the gantry.
Which of the following is the most common symptom post-gad contrast injection?
a. Hives
b. Swelling
c. Emesis
d. Headache - d. Headache
Which of the following are considered anaphylactoid reactions?
a. Tachycardia
b. Hives
c. Difficulty breathing
d. Abdominal pain - a, c [Show Less]