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Physics MRI!! PLEASE help.

A

Ali31a

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Someone please explain me the MRI procedure in simpler terms for a better understanding, here is the MS for MRI:

large / strong (constant) magnetic field B1
nuclei rotate about direction of field / precess (1)
radio frequency / r.f. pulse B1
causes resonance in nuclei , nuclei absorb energy (1)
(pulse) is at the Larmor frequency (1)
on relaxation / nuclei de-excite emit (pulse of) r.f. B1
detected and processed B1
non-uniform field (superimposed) B1
allows for position of nuclei to be determined B1
and for location of detection to be changed (1)
(B6 plus any two extra details, 1 each, max 2) B2 [8]
 
earthling

earthling

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The magnetic field causes all the hydrogen nuclei within the person to precess with the same Larmor frequency.
In order that the hydrogen nuclei in only one small part of the body may be detected, a non-uniform magnetic field is also applied across the patient.
Radio-frequency (RF) pulses are produced in coils near the patient. The nuclei absorb this energy and then ...during the relaxation time, de-excite and emit the RF electromagnetic radiation. This is then amplified, detected, and processed.
 
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