Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: In comparison to the chest radiographs obtained ___ , there is a decrease in the severity and extent of micronodular and interstitial opacities . No new lung opacities . Calcified granuloma in the left upper lung is unchanged since at least ___ . Heart size is top normal without pulmonary vascular congestion or pleural effusions . Median sternotomy wires are midline and intact . A dual chamber pacemaker is unchanged in the position with appropriately placed leads .
    OUTPUT:
    
Improved bilateral parenchymal opacities . It is unclear whether these opacities reflect chronic changes of pulmonary edema or amiodarone toxicity .