Subject: Can the myelin sheath be damaged over time from radioactive isotopes?

I was recently told by a lay-person, that the dye used in tests such as 
mylograms some twenty years ago, can eventually cause damage to the myelin 
sheath, I had three mylograms twenty two years ago and am aware through a 
recent MRI, that there is still dye in my body, is it possible that this dye 
could cause a problem?

Re: Can the myelin sheath be damaged over time from radioactive isotopes?