Question about MRIs

[ALA]

I was diagnosed with MS four years ago. I had two MRIs prior to being diagnosed. The first one was of the brain only. No contrast dye was used. The second MRI was of the brain and spine, and I had an IV of dye the whole time I was in the "tube". I was told that all subsequent MRI's for MS throughout my lifetime would require contrast dye.

This coming Saturday I will be having my third MRI, (brain and spine), and I was told by the MRI lab that they would not be using contrast dye. When I questioned them about it, they really didn't seem to have an answer.

Can anyone enlighten me about this? Is contrast dye always used for MS MRIs to show new lesions (when compared to the initial "non-dye" MRI)? Have they stopped using dye because of radioactivity or expense? Should I be concerned? I live in Canada, if that is pertinent.

Thanks.

[jimmylegs]

hi there, i'm in canada and have had mris with and without contrast. i don't know any reason why a patient would be told all future mris would be done with contrast. i'm far from being an mri expert. all i know is that you can see better with contrast. i understand it helps clarify whether a lesion is active or old/inactive. hope that helps!

[NHE]

I was diagnosed with MS four years ago. I had two MRIs prior to being diagnosed. The first one was of the brain only. No contrast dye was used. The second MRI was of the brain and spine, and I had an IV of dye the whole time I was in the "tube". I was told that all subsequent MRI's for MS throughout my lifetime would require contrast dye.

This coming Saturday I will be having my third MRI, (brain and spine), and I was told by the MRI lab that they would not be using contrast dye. When I questioned them about it, they really didn't seem to have an answer.

Can anyone enlighten me about this? Is contrast dye always used for MS MRIs to show new lesions (when compared to the initial "non-dye" MRI)? Have they stopped using dye because of radioactivity or expense? Should I be concerned? I live in Canada, if that is pertinent.

The contrast dye is typically gadolinium. It is a metal but it's not radioactive. One should drink extra fluids after an MRI scan with gadolinium in order to help your kidneys clear it out of your system. The contrast dye is used to help distinguish new/active lesions from old ones. Specifically, the contrast dye will cross the blood brain barrier at sites of active inflammation due to the immune cells also crossing the blood brain barrier.

NHE

[ALA]

Thanks for the replies. I do understand why contrast dye is used, i.e. to differentiate new lesions from old ones. My question is, then, why do an MRI without the dye, (unless it is your first one)?