Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Left basilar opacity silhouetting the hemidiaphragm is most suggestive of a layering effusion as on prior . Elsewhere , the lungs are clear . The cardiomediastinal silhouette is within normal limits for technique . Atherosclerotic calcifications are noted . Previously seen left central venous catheter is no longer visualized . Tracheostomy tube is also no longer seen .
    OUTPUT:
    
Persistent left - sided pleural effusion without superimposed acute cardiopulmonary process .