MRI "light up" Please help

Ok so I ended up having a Breast MRI done after have 4 surgeries to remove chronic painful cysts and reoccuring nipple discharge. The MRI picked up a "light up" on the other side- not the side with the chronic issue.  The surgen then sent me for a follow up Mammo on the side with the "light up"  They did not see anything.  Here is my concern- I am only 34- I have had many mammo's and the mammo have NEVER seen anything, even the things we could feel and then had removed....why do we trust the mammo in this case...what makes it different? Please help me to understand!  THANKS

[japdip]

MRI is extremely sensitive and may "light up" at the slightest thing. I can't speak to Breast MRI personally but MRI for something else in my case "lit up" due to a tooth abscess that was present many years ago and long since cured. If your Dr.s trust the Mammograms then I believe I would also. MRI isn't the only type of imagery that will show false positives but it's always wise to ck. against other testing.    Regards ....