Stale foci in the lungs are mainly due to the healing of the disease, resulting in the development of fibrosis, calcification of the lung tissue. For example, patients with pneumoconiosis, pulmonary embolism, silicosis, tuberculosis, lung injury caused by pneumonia, the gradual healing of these diseases, the emergence of scars, lung tissue fibrosis, or calcification, these lesions are called intrapulmonary old foci. If the lesions are small, they will not affect your health and usually do not require special treatment, as long as you have regular checkups. If the lesions are more extensive and cause obvious symptoms, affect respiratory function, or even lead to progressive dyspnea, it is necessary to treat them in a timely manner in order to avoid the impact on the body.