Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Opacification at the lung bases may represent atelectasis . Low lung volumes . The cardiac , hilar and mediastinal contours are normal . No pleural abnormality is seen . Elevation of the left hemidiaphragm is a function of gas distended loops of bowel in the left upper quadrant . There is no pneumoperitoneum .
    OUTPUT:
    
Gas distended loops of bowel in the left upper quadrant elevating the left hemidiaphragm . Lung base opacification may represent atelectasis . No pneumoperitoneum .