Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest were reviewed . Compared to the prior study , there has been rapid clearance of a left lower lobe opacity that was most likely due to atelectasis or uncomplicated aspiration . Bibasilar linear opacities likley represent minimal atelectasis . Normal heart , mediastinal and pleural surfaces .
    OUTPUT:
    
Rapid clearing of left lower lobe opacity , which ___ represented atelectasis or uncomplicated aspiration .