Planning from the detail
Specially wound coils, known as gradient coils, allow for the detailed depth imaging which creates slice-by-slice pictures. While the main superconducting magnet creates a very stable magnetic field, these gradient coils create variable magnetic fields during the scan. These fields mean that the magnetic strength within the patient can be altered in specific areas. Since the protons realign at different rates in different tissue types, the relationship between the strength of the field and the frequency of the emitted photons is different for various tissues. Detecting these differences allows for very detailed images.
It’s a matter of reading the alignment