Concept explainers
BIO Magnetic resonance imaging In magnetic resonance imaging (MRI). a patient lies in a strong uniform constant magnetic field
(like the energy needed to turn a compass needle from north to south).
The pulse of an alternating magnetic field of frequency several tens of MHz irradiates the patient's body in the region to be imaged When this alternating field is tuned correctly so that its energy equals the
The MRI imago of an internal body part is made by adjusting an auxiliary magnetic field which varies the external B field over the region being examined so that the probe field energy equals the flipping energy
Why might a herniated disc projecting slightly out from between two vertebrae look different in an MRI image than a nonherniated disc? a The vertebrae adjacent to a herniated disc are closer than vertebrae beside a nonherniated disc.
b. There is a different concentration of hydrogen atoms in bone and in discs.
c. Protons in the herniation produce an image that can be seen.
d. b and c
e. a, b, and c
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