Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are well expanded . In the right cardiophrenic recess there is increase in linear opacities which may not be significantly changed compared with prior exam . Retrocardiac opacity and small linear opacity abutting the left heart border is noted . There is no pleural effusion or pneumothorax . Mild cardiomegaly is stable . Mediastinal and hilar contours are unremarkable .
    OUTPUT:
    
Linear opacities at the lung bases , potentially due to atelectasis or scarring but clinical correlation suggested rearding possibility of infection .