What does "mild bilateral posterior pleural thickening is stable" mean. i'm scared i just looked at my ct report and saw that but my dr never called!?

No worries: Translation: "mild thickening of the lining of the back side of both lungs has not changed since your previous ct scan." diffuse thickening of the pleura usually results from intense inflammation, such as that which occurs during infection. I don't know what your clinical history is or why you have this finding, but your ct scan shows that it has not progressed since your last study.