Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is at the upper limits of normal size . The mediastinal and hilar contours appear stable . Incidental note is made of an azygos fissure , which is a normal variant . Right basilar opacity suggesting atelectasis has cleared . Vague retrocardiac opacity probably referring the left lower lobe persists but has improved . The lungs appear otherwise clear . A right - sided pleural effusion has resolved . A PICC line is been removed . Surgical clips again project over each axilla .
    OUTPUT:
    
Resolution of right pleural effusion and minor associated atelectasis . Improvement in retrocardiac opacity , the latter possibly due to pneumonia versus atelectasis or lower airway inflammation .