Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is borderline enlarged though this is likely accentuated due to low lung volumes . The mediastinal contour is unremarkable . There is crowding of the bronchovascular structures , without overt pulmonary edema demonstrated . Streaky opacities are noted in both lung bases . No pleural effusion or pneumothorax is present . A VP shunt catheter is partially imaged , projecting over the right chest .
    OUTPUT:
    
Low lung volumes with streaky bibasilar opacities , likely atelectasis , but infection can not be completely excluded .