Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Cardiac silhouette size is normal . Mediastinal and hilar contours are unchanged . Pulmonary vasculature is not engorged . Minimal patchy left lower lobe opacity could reflect atelectasis , but infection is not excluded in the correct clinical setting . Right lung is clear . No pleural effusion or pneumothorax is present . Mild degenerative changes are noted in the thoracic spine . Bowel loops within the left upper quadrant the abdomen are distended with gas .
    OUTPUT:
    
Patchy left lower lobe opacity could reflect atelectasis , but infection is not excluded in the correct clinical setting .