Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Left basilar opacity silhouetting the hemidiaphragm similar compared to prior . Left lower lobe rounded opacity posteriorly is again noted likely rounded atelectasis . Superiorly the left lung and right lung remain clear . The cardiomediastinal silhouette is unchanged . No acute osseous abnormalities .
    OUTPUT:
    
No significant change . Left - sided pleural effusion and rounded atelectasis similar to prior . Known paramediastinal soft tissue density is not clearly delineated on this exam .