Will titanium micro plates be an issue when passing through TSA screening?

In 2002, I had titanium micro plates attached to my skull to help keep it together. Since then, I have not had to pass through TSA screening at all, and will likely need to be traveling on either the AMTRAK or a commercial airline. Both will require screening, either to board or when exiting (AMTRAK). I am concerned about personal privacy violations if and when the titanium plates in my head set off metal detectors, and if there is some nature of form I can obtain from a Medical Doctor in advance that will indicate the existence of these plates?