Clients with bad backs clutch onto their MRI scans . Often they are of no value. There is little correlation with  disc degeneration and pain. Most people have  a bit of disc degeneration.
MRI’s are often ordered by doctors for patients as placebo’s
But for those who  want a bit more insight into  MRI magic, here is the best lay persons description I can find. Focus on slides  61-63.
As this slide show says, “ask specific questions”