Lung CT is a commonly used imaging method in clinical practice, and generally there is no need to worry about the detection of old lesions, tiny calcified foci, chronic inflammation, and thickened and disorganized lung texture. 1. Old lesions: If you find streaks in the lungs on lung CT, they are often diagnosed as old lesions. Old lesions are a kind of scar left over from previous tuberculosis or pneumonia, and this condition will not have any effect on the lungs. 2. Tiny calcified foci: This condition may be congenital or acquired. This kind of calcified foci is hard in texture, usually will not have any change, and will not cause any damage to the body. 3. Chronic inflammation: usually there is inflammation left in the lungs in the past, it does not indicate that there is currently an infection and does not require medication. 4. Lung texture thickening disorder, this situation is generally seen in long-term smoking or second-hand smoke inhalation of the population, if usually do not have any uncomfortable symptoms, do not need special treatment, only need to quit smoking and avoid inhaling second-hand smoke. If you have a cough or sputum, it may be caused by a respiratory infection. If you have any discomfort, you should go to the hospital in time to improve the relevant examination, and then carry out targeted treatment.