There are many reasons for the spindle-shaped shadow in the lungs, and the common ones are pneumonia, tuberculosis, lung cancer, and so on. 1. Pneumonia: it is categorized into bacterial pneumonia, viral pneumonia, chlamydia pneumonia, etc. According to the severity of the infection, the size and shape of the shadow of the lungs are different, which can appear as shuttle shadow in the lungs, and at the same time the patient is accompanied by symptoms of coughing, coughing up sputum and fever. 2. Tuberculosis: it is caused by Mycobacterium tuberculosis infection, and there are flaky, shuttle-shaped shadows on chest radiograph or chest CT, mostly located in the upper lobe of the lungs, and the shadows of some patients with more serious conditions are all over the lung field, accompanied by symptoms of coughing, coughing up sputum, hemoptysis, low-grade fever and night sweating. 3. Lung cancer: there may be no obvious symptoms in the early stage, but as the disease progresses, pike-shaped shadow may appear in the upper lobe of the lungs, and irritating cough, chest pain, accompanied by hemoptysis, in addition to weight loss in a short period of time, suggesting the possibility of malignant disease. The appearance of shuttle-shaped shadow in the lungs, must be further examination, close follow-up to clarify the cause of the disease, timely treatment, so as not to delay the condition.