An MRI scan is painless and noninvasive. Depending on the area being scanned, it may take between 15 minutes to an hour. You will be positioned comfortably on a padded table that moves into the machine with the help of your radiology technician, who may communicate with you during the exam.   Because MRI machines use a strong magnetic field, you must remove all metal objects or accessories from your person, which include hairpins, jewelry, coins, and electronic devices. In some cases, you may be allowed to bring someone into the room with you, although they must also be screened for any metal objects prior to entering.   After the MRI, your results will be reviewed by a board certified radiologist, and then sent to your doctor as a report.