Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral chest radiograph demonstrates well - expanded lungs . The right lung is grossly clear with no focal consolidation or appreciable pleural effusion . There is a persistent left - sided pleural effusion and or pleural thickening . Unchanged left chest tube seen along the left hemidiaphram and spine . No appreciable pneumothorax is identified . The cardiomediastinal and hilar contours having normal postoperative appearance . Heart size is top normal . Median sternotomy wires are intact . Incidental note is made of pectus excavatum .
    OUTPUT:
    
When compared to chest radiograph dated ___ , there been no significant changes .