MRI working & Hydrogen atoms in human body
Q. Human body is composed of oxygen, carbon,hydrogen, nitrogen, calcium and phosphorus. Which of these element is useful for creating image using MRI technique?- Published on 30 Oct 15a. Carbon
b. Hydrogen
c. Oxygen
d. All
ANSWER: Hydrogen
- The hydrogen atoms have a strong magnetic moment, so they line up in the direction of magnetic field
- When the body is exposed to a strong magnetic field, the nuclei of the hydrogen atoms are directed into order – stand "at attention".
- When submitted to pulses of radio waves, the energy content of the nuclei changes. After the pulse, a resonance wave is emitted when the nuclei return to their previous state.
- The small differences in the oscillations of the nuclei are detected.
- By advanced computer processing, it is possible to build up a three -dimensional image that reflects the chemical structure of the tissue, including differences in the water content and in movements of the water molecules.
