I would have been more comfortable with that diagnosis with a PET scan or MRI, nonetheless. If this happened to my husband I would insist on it before I could decide the next step.
I believe she did have PET scans, just not the MRI. I think the scan that Trinity_Tx has on her homepage is a PET from 1996. I know there is at least one other PET scan, which was probably from 2002 when she was re=examined at the request of the court.