How MRI Works: Magnetic Fields, Radio Waves & Image Formation

MRI Physics – Simplified

1. Strong magnetic field aligns protons in body water molecules.
2. Radiofrequency (RF) pulses knock protons out of alignment.
3. Signal emission: As protons realign, they release RF energy.
4. Detection & processing: Scanner receives signals; computer reconstructs 3D images based on proton density and relaxation times (T1, T2).
5. Contrast agents (optional): Gadolinium‑based dyes alter tissue magnetism for enhanced visibility of vessels, tumors, inflammation.

MRI provides detailed cross‑sectional images without ionizing radiation, enabling diagnosis of neurological, musculoskeletal, cardiovascular, and oncologic conditions.