Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is normal . The mediastinal and hilar contours are unremarkable . Chain sutures are demonstrated within the left upper lobe with architectural distortion and linear opacities reflective of scarring from prior surgery . Linear opacity within the left lung base likely reflects atelectasis , and overall there is volume loss within the left hemithorax . Blunting of the left costophrenic angle is compatible with a small left pleural effusion . There is no pulmonary vascular engorgement . The right lung is clear . No pneumothorax or focal consolidation concerning for pneumonia is demonstrated . Left rib cage deformity is compatible with prior surgery .
    OUTPUT:
    
Postsurgical changes in the left upper lobe and chest wall . Small left pleural effusion . No radiographic evidence for pneumonia .