Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is normal . The mediastinal and hilar contours are unremarkable . The pulmonary vasculature is not engorged . Patchy opacities are noted within the lung bases , findings which could reflect atelectasis , however infection is not completely excluded in the correct clinical setting . There is no focal consolidation , pleural effusion or pneumothorax . No acute osseous abnormality is visualized .
    OUTPUT:
    
Minimal patchy opacities in the lung bases may reflect atelectasis , but infection can not be excluded in the correct clinical setting .