Old calcified foci in the lungs are usually not serious. If old calcified foci are found in the lungs, they may be calcified foci left after the cure of pneumonia or tuberculosis, or calcified foci caused by long-term exposure to dusty environment, which are usually not accompanied by clinical symptoms and are not serious, so there is no need for special treatment. From the imaging point of view, this kind of old calcified foci will exist for a long time, and should be rechecked regularly in the hospital, and any abnormal changes should be observed through examination. Therefore, if CT examination of the lungs reveals old calcified foci in the lungs, there is no need to worry too much, and it is sufficient to pay attention to follow-up observation. This is especially common in patients with a history of pneumonia and tuberculosis. If new calcified foci appear in the late stage, we should pay attention to it, and suggest that we go to the regular hospital as soon as possible to improve the sputum culture, bronchoscopy and other tests, so as to timely exclude the possibility of lung inflammation and infection or recurrence of tuberculosis.