Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Low lung volumes . Heart size is mildly enlarged , as before . The aorta is calcified , indicating atherosclerosis . The mediastinal and hilar contours are normal . The pulmonary vasculature is normal . Lungs are likely clear , allowing for low lung volumes . No pleural effusion or pneumothorax is seen . There are no acute osseous abnormalities . Multilevel degenerative changes of the visualized thoracolumbar spine . There are degenerative changes of the bilateral acromioclavicular joints .
    OUTPUT:
    
Mild cardiomegaly . Lungs are likely clear , allowing for low lung volumes .