Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Streaky opacification at the left lung base corresponding to the left lower lobe on the lateral view is stable over multiple prior studies and most likely represents chronic atelectasis . There is no new focal opacity concerning for pneumonia . No significant pleural effusion or pneumothorax was detected . The pulmonary vasculature is not engorged . The cardiomediastinal silhouette is within normal limits and stable . There is no free air beneath the right hemidiaphragm . The trachea is midline .
    OUTPUT:
    
Stable chronic atelectasis of the left lower lobe without focal consolidation concerning for pneumonia .