Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The intrathoracic aorta is tortuous and there is mild widening of the mediastinum which is likely due to a combination of difference in technique compared to the prior study as well as increased mediastinal fat pad versus prominence of the brachiocephalic vessels . Lung volumes are low with streaky bibasilar opacities particularly at the right cardiophrenic angle which likely represent atelectasis or vascular crowding due to low lung volumes , however , infection can not be excluded . There is no pleural effusion or pneumothorax .
    OUTPUT:
    
Low lung volumes with bibasilar atelectasis . Streaky opacification at the right cardiophrenic angle is most likely vascular crowding due to low lung volumes , however , infection can not be excluded given the appropriate clinical circumstance .