Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Left pleural pigtail catheter is in unchanged position . The left hydropneumothorax at the lung base has improved while the small apical pneumothorax as well as a tiny medial pneumothorax remain . Extensive opacities in both lung fields , left greater than right , are unchanged . A small right pleural effusion is unchanged . Severe background emphysema is unchanged . Visualized upper abdomen is unremarkable .
    OUTPUT:
    
1 . Interval decrease in the left hydro pneumothorax at the left lung base with persistent small left apical pneumothorax and tiny medial pneumothorax . 2 . Unchanged small right pleural effusion .