Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Previously seen ET tube and transesophageal tubes have been removed . Lung volume is low . Small opacity is identified in the left lung base , improved from before . There is no new consolidation , pneumothorax or large pleural effusion . Cardiomediastinal silhouette is normal size .
    OUTPUT:
    
No radiographic evidence of pneumonia . Left lower lobe atelectasis is improved .