initially Medicare would only cover MRI referred by specialists
GPs CAN refer for MRI in those over age 16yrs for a very restricted range of cases:
MRI brain - unexplained seizures or unexplained chronic headache with suspected intracranial pathology
MRI Cx spine - cervical radiculopathy or cervical spine trauma
MRI knee if aged under 50yrs and no more than 3 per year - acute knee injury with inability to extend knee and suspected meniscal injury, or suspected ACL injury
in Nov 2012, Medicare rebates for MRI were expanded to include MRI scans referred by GP's for children ages < 16yrs
in Nov 2013, some of these were to be expanded to all adults
MRI gadolinium contrast agents are multidentate organic compounds that tightly bind gadolinium, reducing the metal's toxicity and promoting its elimination
studies have shown that gadolinium can be detected in human urine and blood years after exposure, indicating prolonged retention
gadolinium-induced complications may arise from exposure and inter-individual differences in metabolite profiles
formation of gadolinium-rich nanoparticles in the presence of oxalic acid in multiple tissues (eg. skin, kidney and brain) from intravenous MRI contrast agents may be the initial step in rare earth metallosis1)
can cause acute kidney injury, gadolinium encephalopathy, skin plaques, and nephrogenic systemic fibrosis (part of the the scleroderma spectrum disorders, manifesting as pain, skin and muscle induration, joint contractures, and multi-organ involvement)