Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is normal . Mediastinal and hilar contours are unchanged , with mild atherosclerotic calcification of the aortic knob noted . The pulmonary vasculature is normal . The lungs are hyperinflated . Linear opacities within the left lung base are compatible with subsegmental atelectasis . No focal consolidation , pleural effusion or pneumothorax is demonstrated . Moderate degenerative changes are seen at multiple levels in the thoracic spine .
    OUTPUT:
    
No acute cardiopulmonary process .