Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Posterior left basilar opacity may be due to atelectasis versus early consolidation . The right lung is clear . There is no pleural effusion or pneumothorax . The cardiac and mediastinal silhouettes are unremarkable .
    OUTPUT:
    
Posterior left basilar opacity may be due to atelectasis versus early / mild consolidation .