Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is mildly enlarged . The aorta remains tortuous . The mediastinal and hilar contours are stable . The pulmonary vascularity is not engorged . There is no focal consolidation , pleural effusion or pneumothorax . Atelectatic changes are noted at the lung bases . Multilevel moderate to severe degenerative changes are noted within the thoracolumbar spine .
    OUTPUT:
    
Minimal bibasilar atelectasis .