Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes related low . Bibasilar opacities are likely due to atelectasis , but superimposed infection can not be excluded . Heart size appears normal , and there is no pulmonary vascular congestion . Chronic left rib deformities , as seen on the prior CT and radiograph , are unchanged .
    OUTPUT:
    
1 . No evidence of pulmonary vascular congestion . 2 . Basilar opacities are likely due to atelectasis , however in the correct clinical setting , superimposed infection can not be excluded .