In order to undergo an MRI, a patient must get on a table and be sent into the magnet. This is like going into a narrow tunnel. It is not uncommon to have an uncomfortable feeling while within the magnet. Most MRI studies take about 30 minutes to an hour to complete, including time for a few short breaks in between imaging sequences. While the imaging is going on, it is important not to move and to breathe regularly.
Most patients can overcome any claustrophobia and cooperate.
Some may need mild sedation. Many scanners are equipped with special devices that enable the patient to listen to music during the study. As the gradients change during an imaging sequence, they make a rhythmic banging noise which I personally find to induce sleep. Unfortunately, the image quality of these scanners, in general, is not as good as regular magnets. Most life support systems are not usable in the MRI suite.