Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral radiographs of the chest were acquired . There are low lung volumes . The lungs are clear , however . The heart size is within normal limits . The mediastinal contours are normal . There are no pleural effusions . No pneumothorax is seen . Mild elevation of the left hemidiaphragm is not significantly changed . Multilevel degenerative changes of the thoracic spine are redemonstrated .
    OUTPUT:
    
Low lung volumes . No acute cardiac or pulmonary process .