The main mechanism that contributes to T1 relaxation is:
A. ) molecular motion.
B. ) transverse dephasing.
C. ) changes in the applied field strength.
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Spin-spin relaxation is the irreversible dephasing of transverse spin vectors:
A. ) through magnetic field inhomogeneity.
B. ) through changes in echo times.
C. ) through interactions between individual spins.
The MRI signal originates:
A. ) from the emission of energy as the spins relax from the high energy state to the low energy state
B. ) from current induced in the receive coil by net magnetization precessing in the transverse plane
C. ) from current induced in the receive coil by magnetization relaxing along the Z-axis
At an applied field strength of 1.5 Tesla, the water proton Larmor frequency is approximately 63 MHz. At 7 Tesla, the proton Larmor frequency would be:
A. ) the same, 63 MHz
B. ) 294 MHz
C. ) 13.5 MHz
Which imaging modality uses Huntsfield units (HU)?
A. Ultrasound imaging
B. Optical imaging
Computed tomography
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