This study therefore aims to assess current treatment recommended by scientific societies [ 6-13 ] , brain MRI with injection of contrast for the diagnosis and monitoring of brain metastases . The recommended dose of this examination gadolinium is from 0.1 to 0.3 mmol / kg [ 14 ] . Sequences infusion different from one center to the other made : some use the infusion T1, other infusion T2 * . No recommendation establishes whether it is preferable to use one or the other of these sequences.