What are the limitations of chest X-ray?

While chest X-ray examination is of great value in the diagnosis of respiratory diseases, it should also be understood that it has certain limitations: in the early stage of some lesions, although there are certain changes in the pathology, but due to the lesions are relatively small or too subtle, the X-ray can not be shown, such as early stage of lung cancer, lobar pneumonia, congestive stage, etc. The X-ray examination can be used as a diagnostic tool for the diagnosis of respiratory diseases. Some lesions are not characterized by X-ray, and when the clinical manifestations are not obvious, it is more difficult to establish a definite diagnosis. Some lesions are hidden, not easy to be found by general examination, and need special examination (such as CT, MRI, etc.) or imaging examination to confirm the diagnosis, such as tumors in the bronchial tubes.