Hi Nancy (you're my namesake & I'm yours !)
I personally would first, talk to the doctor you feel has the most understanding/knowledge of your MRI's, & ask her/him about the discrepancies; then get the MRI at the same place, with this doctor reading the films.
My pre surg MRI was done at Univ. of Miami. I had my 1 year post surg. MRI at the same place, had it sent to my otoneurology surgeon - he sent it to my neurosurgeon who accurately assessed it. (the radiologist saw a 'tumor' the same size as my pre-surg.- wrong , she didn't see my hx: post AN surg. What she thought was a tumor was the fat placed in the space left by the tumor. ps: Thanks again to those of you who, when I wrote in freaking out about having a 'tumor' that it was really the fat. You guys had experience, there you go! ).
This year I will have my MRI done at the same place, results sent to my PCP & my neurosurgeon - who gives me the answer via email !
Always good thoughts, Nancy