Welcome to your MRI - A Name [The gradient that is turned on just before the 180 degree rephasing pulse is known as the ______.] Slice selection gradient Phase encoding gradient Frequency encoding gradient None of the above None . [Within a perfect magnetic field all protons rotate at _______.] Different frequencies The same frequency Undetermined frequencies None of the above None . [The process during the prescan that determines the amount of signal that is received is known as _____.] Center frequency adjustment Transmit gain adjustment Receive attenuation adjustment Impedance matching None . [The method of MRI field containment that uses additional magnets outside the cryogenic area of the magnet is known as _____.] Active shimming Passive shielding Active shielding Passive shimming None . [The Z gradient alters the magnetic field strength along which axis?] Horizontal axis Vertical axis Long axis Short axis None . [In a T2 weighted image, a long TE is used to ______.] Maximize T2 effects Minimize T2 effects Maximize TI effects Minimize TI effects None . [Which of the following is a disadvantage of fast spin echo pulse sequences?] Increased effects of flow motion Bright fat on T2 weighted images Increased resolution Both A and B None . [On a TI weighted image of the knee, cortical bone appears ______ to all other tissues.] Hyperintense Hypointense Isointense None . [Which of the following is the conventional technique used to produce a black appearance in vascular structures?] Short TE, Short TR, Pre-saturation pulse Long TE, Short TR, Gradient moment nulling Long TE, Long TR, Respiratory compensation None of the above None . [Which of the following is a possible side effect of gadopentetate dimeglumine?] Mild, temporary headaches Nausea Vomiting All of the above None . [Chemical shift artifact occurs in which direction of the MR image?] Phase encoding direction Frequency encoding direction Slice selection direction None of the above None . [Which of the following people won the 1952 Nobel Prize for their NMR research?] Felix Bloch I.I. Rabi Edward Purcell Both A and C None . [In plane pixel size can be determined by which of the following methods?] Dividing the FOV by the number phase and frequency steps Dividing the NEX by the FOV Dividing the TR by the NEX Dividing the TR by the slice thickness None . [The diffusion of fluid thorough a semipeITI1eable membrane such as the wall of a living cell is known as _____.] Hydrosis Ionization Osmosis None of the above None . [The area of K space that is filled with the steepest phase encoding gradient slopes is known as _______.] Central lines Outer lines Positive lines only None of the above None . [Magnetic susceptibility artifact can be used to help diagnose what pathology?] Tom meniscus Herniated nucleus pulposis Pituitary adenoma Hemorrhage None . [The type of spin echo pulse sequence that begins with a 180 degree inversion RF pulse and is followed by a 90 degree excitation pulse is known as ______. ] Echo planar Gradient echo Inversion recovery Gradient reversal None . [In a T2 weighted image, tissues with short T2 relaxation times appear ______.] Hyperintense Hypointense Isointense None of the above None . [Noise that generally degrades overall quality of an MRI image is known as _______.] Inherent noise interference Random noise interference Discrete noise interference None of the above None . [The type of RF coil configuration that uses a series of independent coils to create one image is known as a _____.] Surface coil Phased array coil Quadrature coil Gradient coil None . Time's up
