Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes remain low . The heart size remains moderately enlarged but unchanged . The mediastinal contours remain similar , with a markedly tortuous aorta again demonstrated . There is crowding of the bronchovascular structures , but without overt pulmonary edema demonstrated . Mild atelectatic changes are also noted at the lung bases . No pleural effusion , focal consolidation or pneumothorax is seen . There are moderate multilevel degenerative changes in the thoracic spine .
    OUTPUT:
    
Low lung volumes with mild bibasilar atelectasis .