MRI. I was in the middle of a migraine each time. It was very painful bc of how loud it was and my noise tolerance during my migraine. I have also had cat scans done, once at an ER visit, and once during a neurological work up for my migraines. I've been suffering from migraines for over 40 years. I've been to the ER quite a few times for more intense migraines or ones where I can't get them to stop.