Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low . The cardiac silhouette appears unchanged in size as are the mediastinal contours . Continued opacification of the left lung base likely reflects a combination of a small left pleural effusion and atelectasis . Size of the pleural effusion appears unchanged . Right lung is grossly clear . No pneumothorax is identified . No acute osseous abnormality is seen .
    OUTPUT:
    
Low lung volumes with persistent left basilar opacification compatible with a small left pleural effusion and associated left basilar atelectasis . No pneumothorax .