Based off of Nuclear Magnetic Resonance (NMR)
- You body is mostly made up of water, and these water molecules are magnetic (because of hydrogen atoms)
- When you enter an MRI scanner, the strong magnetic field of the large electromagnet causes causes most of the water molecules in your body to align with it.
- Some water molecules dont align as easily Small coils produce varying radio frequencies
- These “tip” the aligned waters a bit for a brief moment, and when the waters realign with the main field, they emit a radio frequency that we can read
- different tissues relax at different rates which we can read and post process into an image To get slices the coils in the MRI are gradients of different magnetic fields, so we get different resonance at different frequencies, which we can use to map position to the readings we get.