Moreover, the apparatus is definitely less noisy. Most make-ups containing metal components, it is recommended not to make up before an examination of the head or neck. Any dental device should be removed if possible, as well as hearing aids. A friend or a parent may stay with you during your examination if you like. If you think you could be pregnant, it is safer to postpone your examination until next period.
Complete immobility is required during the sequences.
The repetitive noise you hear is normal, it is due to fast current inversions in the gradient coils. If this noise bothers you, just ask for ear plugs. Pulsed radio waves of short duration are then locally applicated to modify proton orientation. However, magnetic field interacts with metallic objects, resulting in image degradation. As any iron oject is strongly attracted by the magnet, some security precautions are mentioned.