Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Cardiac silhouette size remains mildly enlarged . The aorta is diffusely calcified . Bilateral paramediastinal and opacities are compatible with post radiation changes . Mediastinal contour is similar , and known subcarinal mass as well as mediastinal lymphadenopathy is better assessed on the previous CT . Pulmonary vasculature is normal . Streaky atelectasis is seen in the left lung base . No focal consolidation , pleural effusion or pneumothorax is present . There are no acute osseous abnormalities . Previously noted left upper lobe pulmonary nodule is better demonstrated on CT .
    OUTPUT:
    
Minimal atelectasis in the left lung base . Otherwise unchanged exam .