Bilateral pulmonary cornu foci are a morphologic description of a pathology found in the lungs by imaging. There are very different causes, and it is common to have clinically disseminated tuberculosis with hematogenous dissemination and metastatic tumors in the lungs, such as extra-pulmonary bone cancer metastasizing to the lungs. Patients will have different degrees of clinical manifestations, such as irritating cough, hemoptysis, which may be accompanied by chest pain, chest tightness, shortness of breath, and a series of symptoms such as low fever, night sweats, emaciation, and weakness. X-ray, CT or MRI of both lungs can reveal the extent and severity of the lesion. Blood tests as well as sputum smears and PPD tests can be performed. Biopsies of both lung cornea lesions can also be obtained by bronchial fiber endoscopy or by puncture for pathological examination to clarify the possible causes of the above mentioned lesions.