Solid nodular proliferative foci in the lungs are usually seen in the case of previous tuberculosis infection, and proliferative nodules appear in the lungs due to incomplete absorption in the course of tuberculosis treatment. This kind of nodule is generally considered to be caused by tuberculosis, but this kind of nodule is not contagious, and does not need to be given anti-tuberculosis drugs again, only need to dynamically follow up the chest high-resolution CT, to observe whether the nodule is stable or not. Another situation, solid nodules in the lungs can also be seen in the formation of chronic pneumonia inflammatory pseudotumor, inflammatory pseudotumor mainly refers to the imaging foci of the lungs below 3cm solid nodules, this nodule is mostly formed by granuloma, CT can be judged to be proliferative nodules.