Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are well expanded . The right lung is clear without focal opacities . The left lung demonstrates apical scarring with hilar traction unchanged from prior . The cardiomediastinal and hilar contours are unremarkable . There is no pleural effusion or pneumothorax . Air cavities noted in the anterior mediastinum in the lateral view were seen in the prior CT of the thorax and represent postop changes . Surgical clips are noted in the upper abdomen . Of note , aneurysmatic dilatation of the ascending aorta is better evaluated on CT .
    OUTPUT:
    
No evidence of acute intrapulmonary process . Left apical scarring and mediastinal air aerated cavities represent stable post treatment changes . Of note , aneurysmatic dilatation of the ascending aorta is better evaluated on CT .