Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Evaluation is slightly limited due to lordotic positioning . Moderate enlargement of the cardiac silhouette is unchanged . Mediastinal and hilar contours are within normal limits . Previous pattern of pulmonary edema has improved with only minimal residual vascular congestion noted . Retrocardiac patchy opacity may reflect atelectasis . No large pleural effusion or pneumothorax is visualized . There are no acute osseous abnormalities .
    OUTPUT:
    
Patchy retrocardiac opacification may reflect atelectasis . Mild pulmonary vascular congestion , improved from the prior exam .