Garry: You are right. It's more like a CT scan will show if the MAC is evolving, tree in bud, etc. but it will not diagnose MAC. In fact, when I first had a CT scan they diagnosed me with severe asthma, Luckily a savvy doc did a bronch, and sputum tests and I learned what I had but by then I was coughing up blood. 2 years of the big 3 drugs left me with tinnitus, glaucoma, really messed up bowels, stomach cramps, wierd skin rashes, heart palps, loooow blood pressure, and way under weight. Mom died at 94, dad died at 104, neither took any pills for anything!!!, the pills demolished me. Just had a CT scan yesterday so will see the progression after 2 years no drugs. i actually feel pretty good now, tired but I move well and enjoy life. Learn as MUCH as you can, you'll find you know more than some docs. Keep on top of new research. xo