Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Low lung volumes results in bronchovascular crowding . Minimal linear atelectasis at the left lung base is unchanged . There is no focal consolidation , pleural effusion or pneumothorax . Heart size is normal . Mediastinal silhouette and hilar contours are normal . No displaced rib fracture is identified .
    OUTPUT:
    
No pneumonia , edema , or effusion .