MRI's, CAT's or PET's???
Me? I've found the PET's to be the most amazing diagnostic tool to come down the road since peanut butter! Expensive yes! Accurate to beyond a T? Absolutely! Saved ME from having a heap of 'exploratory' things done to me for different issues that crop up! And, I've had all three tests, first two with and without contrasts.... PETs get detail that the others simply don't!
My last PET caught three different med issues that everydoc was floundering on about... So? That one test saved me from having about 5 others!
As for testing every year? IF Pets? I'D go in a flash! They have got to be the easiest tests to take and get results on ever [in my opinion?] ! Essentially, you get either your whole body or part done and OVER. That's it till next time! Just don't try to fly and go thru airport screening for a few days afterwards? You mite just GLOW! [Not really, but you sort of feel that way!]
Yes, I've a bias, but it's also attached to peace of mind! I'm less than 6months from year FIVE of BC! Peace of MIND IS invaluable!
Hugs faith and HOPE in heaps! - j 's!!!!!!!!

Basic PET Info: http://en.wikipedia.org/wiki/Positro...ion_tomography - It's tech, but good to learn the 'tech talk'! It'll do you well to learn in the long run.