Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The right - sided Port - A - Cath and tracheostomy tube are overall unchanged in position . Lung volumes continue to be low . Compared to the radiograph from 6 days prior , the parenchymal opacity at the left lung base has decreased in extent , with better aeration of the left lower lung . No larger pleural effusions . No pneumothorax .
    OUTPUT:
    
Interval decrease in the extent of the left lower lung opacity . No new focal consolidation identified .