Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low . Bibasilar linear opacities likely represent atelectasis . There is mild pulmonary vascular prominence , which may be exaggerated by low lung volumes . Likely calcified nodule seen in the left upper lung . Heart and mediastinal contours are difficult to evaluate in the setting of low lung volumes . No pleural effusion or pneumothorax is detected .
    OUTPUT:
    
Low lung volumes with bibasilar atelectasis . Underlying infection is not completely excluded .