Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Relatively low lung volumes are seen . Retrocardiac opacity is identified Elsewhere the lungs are clear of consolidation or effusion . The cardiomediastinal silhouette is within normal limits . Median sternotomy wires are noted . No acute osseous abnormalities detected .
    OUTPUT:
    
Left lower lobe consolidation may be secondary to atelectasis although infection is also possible .