So I get an annual CT scan with contrast at the University of Minnesota Minneapolis. I go to the same imaging center and get in the same machine every year for the past nine years. I think it really helps to compare apples to apples in terms of using the same diagnostic imaging center and the same Technology consistently. The problem of course is that you get individual radiologists and technicians who do things a little differently each time and so your results are going to be a little bit different. The most important part is to get consistent scans and not panic if they vary by one or 2 mm. That’s been pretty typical in my experience. Initially I got scans every six months for the first five years after I dissected. There were constant differences and the variability comes from 1 million different things that you can’t wrack your brain over. The fact that you’re getting scans consistently is important, but try to get them scheduled with the same docs in the same Location using the same technology if that’s implicated. Good luck, and I understand your frustration. Recognize that it comes from your desire to control something that you can’t control other than to keep your blood pressure down, keep your heart rate down, and keep your stress down.. Trust your medical team. Peace.