Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is normal . The mediastinal and hilar contours are unremarkable . Rounded opacity within the posterior left aspect of the left lung base corresponds to a fat containing diaphragmatic hernia ( Bochdalek hernia ) , as seen on the prior CT abdomen and pelvis from ___ . Apart from a linear opacity in the right middle lobe which likely reflects scarring , lungs are clear . No pulmonary vascular congestion , pleural effusion or pneumothorax is seen . There are no acute osseous abnormalities .
    OUTPUT:
    
No acute cardiopulmonary process .