Welcome to your MRI - A Name [The P wave of the ECG represents which phase of the cardiac cycle?] Atrial systole Ventricular systole Ventricular diastole Atrial diastole None . [The liquids used to cool the wire in the main magnetic field of a superconducting magnet are known as _____.] Neon gases Plasma Cryogens None of the above None . [To minimize MRI contrast agent's toxicity, the agent should be _____.] Excreted intact by the kidneys Excreted intact by the gallbladder and intestines Released within the body Both A and B None . [With the parameters given, which protocol gives the highest signal to noise ratio?] Thick slice/Low TE/Large FOV Thin slice/High TE/Small FOV Thick slice/High TE/Small FOV Thin slice/Low TE/Small FOV None . [The difference in brightness between two regions of an image is known as _______.] Signal to noise Image contrast Spacial resolution None of the above None . [The process that uses mathematical conversions to calculate the amplitude of individual frequencies is known as _______.] Fast Fourier transfonnation Free induction decay Larmor equation None of the above None . [The artifact that is produced by overlapping radio frequency pulses in adjacent slices is known as ______.] Cross excitation artifact Aliasing artifact Truncation artifact Phase mismapping artifact None . [TOF MRA is most sensitive to blood flow that flows in what direction in relation to the slice?] Parallel Perpendicular None . [The method of MRI field containment that uses steel lining in the walls of the magnetic room is known as _____.] Active shimming Passive shielding Active shielding Passive shimming None . [Figure displays an example of what type of artifact?] Truncation Aliasing Cross excitation Chemical shift None Comment . [The effects of entry slice phenomenon are dependent upon which factor( s)?] Repetition time Slice thickness Velocity offlow All of the above None . [The gradient echo pulse sequence that is characterized by an echo time that is longer than its repetition time is known as ______.] Echo planar Steady state free precession Spin echo Fast spin echo None . [The precessional frequency of hydrogen nuclei that experience increased magnetic field strength due to gradient coils ______.] Increases Decreases Stays the same None . [The amplitude of the phase and frequency encoding gradients determines the dimension of what parameter?] FOV TR TE NEX None . [The magnitude of time of flight phenomenon effects is dependent upon which factor(s)?] Velocity of flow TE Slice thickness All of the above None . [10,000 gauss is equal to _______.] 1.0 amp 1.0 ohm 1.0 tesla 10 tesla None . [The gradient that is turned on during the application of the 90 degree excitation pulse and the 180 degree RF pulse is known as ______.] Slice selection gradient Phase encoding gradient Frequency encoding gradient None of the above None . [Blood flow that has high velocities in the center of the vessel but spirals near walls of a vessel due to a stricture is known as what type of flow?] Turbulent flow Laminar flow Vortex flow Stagnant flow None . [The number of 180 degree rephasing pulses performed in a fast spin echo pulse sequence is known as its ______. ] Turbo factor Inversion factor Echo train length Both A and C None . [The time that both fat and water are in phase with each other is known as ______.] Periodicity Repetition time Inversion time None of the above None . Time's up
