I would not attempt to litigate this. No lawyer would take the case.

There is no real evidence that MRI is damaging. However, no one should undertake the test if they have risk aversion. It is a risk/benefit ratio. Same as with drug usage. Everything has risk. Do you use a cell phone, a stove, a car? Everything in life poses risk.

MRI causing PN? That is looking for a needle in a haystack.