Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is top normal . Mediastinal and hilar contours are unchanged . Pulmonary vascularity is normal . Lung volumes are slightly low . There is minimal atelectasis in the lung bases , but no focal consolidation . No pleural effusion or pneumothorax is identified . No acute osseous abnormalities are detected . Clips in the right upper quadrant of the abdomen are compatible with prior cholecystectomy . A right - sided VP shunt catheter is noted .
    OUTPUT:
    
Low lung volumes with mild bibasilar atelectasis .