Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is normal . The aortic knob is mildly calcified . The mediastinal and hilar contours are unremarkable . The pulmonary vascularity is normal and the lungs are clear without focal consolidation . No pleural effusion or pneumothorax is demonstrated . There are multilevel degenerative changes in the thoracic spine .
    OUTPUT:
    
No acute cardiopulmonary abnormality .