Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are markedly low , which accentuates bronchovascular markings and enlarges the cardiac silhouette . Given that , the heart is enlarged . The course of the aorta is irregular consistent with a known large thoracic aortic dissection . Calcification along the thoracic aorta is demonstrated . Subtle basal opacities likely represent atelectasis . No overt pulmonary edema . Of note , soft tissue density overlying the left apex is most likely related to overlying soft tissue .
    OUTPUT:
    
Markedly low lung volumes and bibasilar opacities suggest atelectasis however infection should be considered in the appropriate setting . Markedly widened mediastinum is related to a large known aortic dissection .