Hi Kel. An mra is looking at blood vessels. They can do a time of flow, using a programme on the scanner or a time of flow using contrast, which I think they call a dynamic mra.
I had one when they thought my problem was arterial flow causing the cramping.
I had one because a cardiologist could detect no pulses in my legs, I thought that was weird. I had the scan and just as I thought, I had wonderful arterial and venous flow.........another dead end!
I wouldn't go down that path unless you had evidence of blood flow issues. I just had too much fat to feel my pulses? Lost the weight now