Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is within normal limits . The mediastinal and hilar contours are normal . Thre is a nodular opacity projecting over the left lower lung . There is no obvious pleural effusion or pneumothorax in light of the patient 's supine positioning . No obvious displaced rib fracture is seen .
    OUTPUT:
    
No acute cardiopulmonary process ; no displaced rib fracture . Nodular density projecting over the left lower lung ; correlation with chest CT suggested .