Hi,

I have a PhD in MRI physics and still work in MRI research, but I'm not a clinician. You should discuss your scan and any concerns with the radiographer and, if necessary, ask to speak to a doctor.

I have been scanned for many 10's of research projects; you should experience no adverse effects from the scan. I've never had a contrast injection, and, as stated by others, you may or may not need one depending on what the scan is for. The contrast agent used in routine MRI (gadolinium based) is different from that used in x-ray (iodine) and is safe in people with adequate kidney function. Many MRI units will check your kidney function before administering contrast agent.

In fact, the greatest risk is from metallic objects and implants, which can become projectiles in the strong magnetic field. Metallic implants can heat up during the scan or move in the magnetic field. However, many modern implants have been tested and certified as safe.

The scan will be very noisy and you must keep still. You could be in the scanner between 20 minutes and 2 hours, but 30 - 60 minutes is fairly typical.