Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Previously visualized scarring in the left lung base has remained stable . Otherwise , the lungs are clear with no evidence of a consolidation , effusion , or pneumothorax . The cardiomediastinal silhouette remains stable . Visualized osseous structures are normal . Calcifications of the aortic knob are again noted .
    OUTPUT:
    
No acute cardiopulmonary process .