Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is normal . The median sternotomy wires are normal . There is a small decrease in the left lung base lucency , of uncertain clinical relevance given the absence of prior imaging . The right lung is clear . There is no pneumothorax or pleural effusions . The hilar and mediastinal contours are otherwise unremarkable . The median sternotomy wires appear intact .
    OUTPUT:
    
Small decrease in the left lung base lucency , which in the absence of prior imaging may be secondary to progressive consolidation or resolution of a previously seen consolidation . If prior imaging is available , an addendum could be issued . No other focal consolidations suggestive of pneumonia is identified .