difference in intepreting an MRI result

[krysy8]

i wonder if-when you have an MRI done, if there woudl be a difference in the intepretation of the results with different radiologist. (or who ever types up the report)
it seems the doctors go off of the written report. What if the person looking at it misses something or misreads it. Is this possible? If a person was to take the IMAGES to someone else, would they be able to come up with info on it?
Also-how often should one have a MRI? if there has been no injury but still constant pain-how often should one be repeated?
Is an MRI enough? or should a CT scan be done as well, or nerve conductivity testing as well???
What are your thoughts/