Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest are obtained . There is significant interval improvement in lung aeration . Vague reticular opacities persist in the perihilar regions , possibly representing residual pneumonia . No definite signs of CHF , pleural effusion , or pneumothorax . Heart and mediastinal contours appear normal . Interval removal of the endotracheal and nasogastric tubes . Bony structures are intact .
    OUTPUT:
    
Significant improvement in pulmonary aeration with persistent reticular perihilar markings , possibly representing residua of recent pulmonary infection .