Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is normal . The aorta is mildly unfolded . Mediastinal and hilar contours are otherwise unremarkable . The pulmonary vascularity is normal . Patchy opacity in the left lower lobe is concerning for pneumonia . No pleural effusion or pneumothorax is identified . There are no acute osseous abnormalities .
    OUTPUT:
    
Patchy left lower lobe opacity is concerning for pneumonia . Followup radiographs after treatment are recommended to ensure resolution of this finding .