Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compared with the prior chest radiograph , there has been slight improvement in the previously described middle and lower lobe parenchymal opacity concerning for pneumonia . No other significant changes are noted . No larger pleural effusions or pneumothorax . Median sternotomy wires are intact . No change in the right pectoral pacemaker position .
    OUTPUT:
    
Slight interval improvement in the previously described middle and lower lobe parenchymal opacity concerning for pneumonia .