Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral radiographs of the chest demonstrate intact median sternotomy wires . The lungs are clear . The cardiac contour is top normal . The mediastinal contour is normal aside from a slightly tortuous ascending aorta . Chronic elevation of the right hemidiaphragm is again noted . No pleural effusion or pneumothorax is seen .
    OUTPUT:
    
No evidence of pneumonia , pleural effusion or pneumothorax .