MRSE EXAM QUESTIONS WITH CORRECT SOLVED SOLUTIONS
1. Formula for temperature change in a patient: dTp/dt = SAR/C, where C = 4186 J/kg, Tp = temperature
2. How much does liquid helium expand when transitioning to gaseous heli- um?: >700x
3. Electric field density ( JE) formula: JE = Conductivity x electric field strength x B0 x V where V = velocity?
4. What is the most accurate way to measure energy dose to the patient?: B1 + rms
5. Kinetic stability: The rate at which a gadolinium agent dissociates
6. Thermodynamic stability: the change that a gadolinium agent will transmetallate
7. Diamagnetic: Very small negative magnetic susceptibility (X), two electrons in an orbital
8. Paramagnetic: Very small positive magnetic susceptibility (X), one electron in an orbital
9. Ferromagnetic: very large positive magnetic susceptibility (X), domains of directional magnetism that can align with an external field, retains magnetism
after being removed from field
10. RF Pulse power (heating) formula: Power = Flip Angle ^2 x (Tp / Tr) where Tp = pulse duration, Tr =
11. Slew rate formula: Maximum Gradient Strength (mT/m) / Rise Time (ms)
,12. What parameters can be changed to reduce Peripheral Nerve Stimulation (PNS)?: Increase rise time (reduces slew
rate), decrease matrix/phase encoding (reduces slope of gradient), increasing slice thickness (shallower slice selection gradient), increase FOV (shallower frequency
encoding gradient), phase noise-canceling (opposite frequency to noise), increase echo time TE
13. Nitinol is (paramagnetic/diamagnet/ferromagnetic): paramagnetic
14. What quantitative property of the gradient coils is responsible for Periph- eral Nerve Stimulation
(PNS)?: slew rate
15. What contrast agents are the most stable?: macrocyclic, ionic
16. What is a common dose of gadolinium?: 0.1 mmol/kg
17. In what direction relative to the magnetic flux will the strongest Lenz's force be produced?: antiparallel
18. What is the ASTM duration of time defined for heating effects?: 15 mins continuous scanning
19. Where is translational force at a maximum?: edge of bore
20. Where is translational force at a minimum?: isocenter
21. Where is rotational force at a maximum?: isocenter
22. Where are gradient fields at their maximum?: inner periphery of bore
, 23. Do gradient fields extend outside the bore?: yes
24. Do RF fields extend outside the bore?: no
25. What kind of stainless steel is NOT ferritic?: 316L austenitic stainless steel
26. Cobalt is (paramagnetic/diamagnetic/ferromagnetic): ferromagnetic
27. MP35N alloy is (ferrous/not ferrous): not ferrous
28. How much risk does a temporary epicardial pacing wire pose?: minimal risk because the wires are usually not
ferrous and have a very short length that will not create much heating
29. What is the minimum type and amount of padding to reduce a proximity or loop burn?: 1 cm foam pad
(thick enough, not impacted by sweat)
30. In which zones will a patient change for a fixed and mobile MRI?: fixed: Zone 2. mobile: Zone 3
31. Who is allowed to bring a patient into zone 4?: Only level 2 MR personnel
32. Who is allowed to bring a patient into zone 3?: Level 1 and 2 MR personnel
33. Force product formula: Bo x gm [T^2/m], where Bo = static magnetic field and gm = magnetic spatial gradient (dB/dx)
1. Formula for temperature change in a patient: dTp/dt = SAR/C, where C = 4186 J/kg, Tp = temperature
2. How much does liquid helium expand when transitioning to gaseous heli- um?: >700x
3. Electric field density ( JE) formula: JE = Conductivity x electric field strength x B0 x V where V = velocity?
4. What is the most accurate way to measure energy dose to the patient?: B1 + rms
5. Kinetic stability: The rate at which a gadolinium agent dissociates
6. Thermodynamic stability: the change that a gadolinium agent will transmetallate
7. Diamagnetic: Very small negative magnetic susceptibility (X), two electrons in an orbital
8. Paramagnetic: Very small positive magnetic susceptibility (X), one electron in an orbital
9. Ferromagnetic: very large positive magnetic susceptibility (X), domains of directional magnetism that can align with an external field, retains magnetism
after being removed from field
10. RF Pulse power (heating) formula: Power = Flip Angle ^2 x (Tp / Tr) where Tp = pulse duration, Tr =
11. Slew rate formula: Maximum Gradient Strength (mT/m) / Rise Time (ms)
,12. What parameters can be changed to reduce Peripheral Nerve Stimulation (PNS)?: Increase rise time (reduces slew
rate), decrease matrix/phase encoding (reduces slope of gradient), increasing slice thickness (shallower slice selection gradient), increase FOV (shallower frequency
encoding gradient), phase noise-canceling (opposite frequency to noise), increase echo time TE
13. Nitinol is (paramagnetic/diamagnet/ferromagnetic): paramagnetic
14. What quantitative property of the gradient coils is responsible for Periph- eral Nerve Stimulation
(PNS)?: slew rate
15. What contrast agents are the most stable?: macrocyclic, ionic
16. What is a common dose of gadolinium?: 0.1 mmol/kg
17. In what direction relative to the magnetic flux will the strongest Lenz's force be produced?: antiparallel
18. What is the ASTM duration of time defined for heating effects?: 15 mins continuous scanning
19. Where is translational force at a maximum?: edge of bore
20. Where is translational force at a minimum?: isocenter
21. Where is rotational force at a maximum?: isocenter
22. Where are gradient fields at their maximum?: inner periphery of bore
, 23. Do gradient fields extend outside the bore?: yes
24. Do RF fields extend outside the bore?: no
25. What kind of stainless steel is NOT ferritic?: 316L austenitic stainless steel
26. Cobalt is (paramagnetic/diamagnetic/ferromagnetic): ferromagnetic
27. MP35N alloy is (ferrous/not ferrous): not ferrous
28. How much risk does a temporary epicardial pacing wire pose?: minimal risk because the wires are usually not
ferrous and have a very short length that will not create much heating
29. What is the minimum type and amount of padding to reduce a proximity or loop burn?: 1 cm foam pad
(thick enough, not impacted by sweat)
30. In which zones will a patient change for a fixed and mobile MRI?: fixed: Zone 2. mobile: Zone 3
31. Who is allowed to bring a patient into zone 4?: Only level 2 MR personnel
32. Who is allowed to bring a patient into zone 3?: Level 1 and 2 MR personnel
33. Force product formula: Bo x gm [T^2/m], where Bo = static magnetic field and gm = magnetic spatial gradient (dB/dx)
