Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The patient is status post median sternotomy and CABG . The cardiomediastinal and hilar contours are within normal limits . Lung volumes are slightly low . There is a trace right pleural effusion and a small left pleural effusion . There is a small opacity at the base of the left lung which may represent compressive atelectasis . Slightly increased opacity involving the right lower lobe is improved from the prior examination on ___ . No pneumothorax is detected . There is no evidence of pulmonary edema .
    OUTPUT:
    
Compared to previous postoperative radiograph of ___ , bilateral pleural effusions have decreased in size and a right PICC basilar focus of atelectasis has essentially resolved . Left lower lobe opacity has decreased in extent and may reflect slowly resolving atelectasis or potentially a focus of pneumonia in the appropriate clinical setting .