Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Cardiac , mediastinal and hilar contours are normal . Pulmonary vasculature is normal . Patchy opacity in the left lower lobe is concerning for pneumonia . Right lung is clear . No pleural effusion or pneumothorax is seen . Right subdiaphragmatic free air is compatible with recent surgery . Clips are seen in the right upper quadrant of the abdomen .
    OUTPUT:
    
Left lower lobe patchy opacity concerning for pneumonia . Followup radiographs after treatment are recommended to ensure resolution of this finding . Subdiaphragmatic free air is compatible with recent surgery .