I don't know if this will make you feel better or not...but they did see catch something on my c-spine .7 strength open MRIs.
The bad part was that the quality was so c rappy they didn't know what it was. To me that just translates into...your lesions have to be pretty prominent to be caught on that type of machine.
Do they react to very cold temperatures (changing colors as well) or is it just the warm water?