Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest were provided . Lung volumes are low with probable bibasilar atelectasis . The heart size appears top normal . No signs of pulmonary edema . Mediastinal contour appears normal . No effusion or pneumothorax . Bony structures are intact .
    OUTPUT:
    
Mild bibasilar atelectasis . No convincing signs of pneumonia .