Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP chest radiograph . Post - surgical changes are noted in the mid trachea consistent with known prior surgery . Widened mediastinum has improved . The lungs are clear . The cardiomediastinal silhouette is normal . There is mild levoscoliosis . There is no pleural effusion or pneumothorax .
    OUTPUT:
    
No acute cardiopulmonary process .