Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Cardiomediastinal contours are stable . Multifocal predominately linear atelectasis is present in both lower lungs . A more focal patchy opacity in the left retrocardiac region may reflect more extensive atelectasis , but differential diagnosis includes aspiration and developing infectious pneumonia . Small pleural effusions are also noted .
    OUTPUT:
    
Patchy left retrocardiac opacity , which may reflect atelectasis , aspiration or early pneumonia . Short - term followup radiographs may be helpful in this regard . Bibasilar linear atelectasis .