Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A subtle opacity in the left lung base could reflect a developing pneumonia . There is no pneumothorax . There is no vascular congestion or pulmonary edema . Mild blunting of the right costophrenic angle suggests a small effusion . Heart size is bordelrine and aorta is slightly tortuous . Cardiomediastinal and hilar contours are within normal limits .
    OUTPUT:
    
1 . Subtle left basilar opacity , possibly a developing pneumonia . 2 . Blunting of right costophrenic angle -- ? small effusion vs pleural thickening .