WHATEVER Procedure you do have
MAKE SURE THE OPERATORS OF THE MRI (open or closed) KNOW THAT YOU ARE A CLAUSTROPHOBIC
that way they will be prepared for anything, and will know if they need to stop the procedure prematurely in order to assist you if you do have a panic attack
they can even sedate you beforehand so long as it does-not interfere with the region of interest (depending if it is an f-MRI or not, which measures activity in the brain and responses to music/light/etc.... that would be affected by sedatives) normal (non-functional) MRI just measures the tissues involved, looking for abnormal anatomical features, in comparison to measuring neurological responses
I know for instance that it is the normal procedure in Australia that all children are sedated beforehand, but most f-MRI stuff is not used in kids anyway due to its research functions... etc.
