Lung nodular shadows are dense shadows that are higher than the density of the lung tissue found on a chest CT or chest X-ray. During a chest CT or chest X-ray, the lung tissue contains a large amount of alveoli and gas, and it appears as a low-density image, i.e., a darker and darker image. When the lung tissue is diseased, etc., and the lung tissue is localized, the density of the lesion is higher than that of the surrounding normal lung tissue, and the image shows high density, i.e., it is whitish and bright. Lung nodules may be caused by pneumonia, tuberculosis, lung scarring, lung cancer, etc. The edges of lung nodules may be clear or unclear, and the shape of lung nodules may be round or irregular, and the diameter of lung nodules may be less than or equal to 3cm, which can be categorized as benign or malignant nodules. When you find the shadow of lung nodule, it is recommended to follow the guidance and advice of professional doctors and arrange the treatment plan reasonably.