Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are persistently low . Heart size remains mildly enlarged . Mediastinal and hilar contours are similar . Pulmonary vasculature is not engorged . Patchy opacities in the left lung base likely reflect atelectasis . Right lung is clear . No focal consolidation , pleural effusion or pneumothorax is present . No acute osseous abnormalities detected .
    OUTPUT:
    
Patchy left basilar opacity , likely atelectasis . Infection can not be excluded in the correct clinical setting .