Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest . A large retrocardiac opacity is again seen , consistent with a known large hiatal hernia containing segments of bowel . Blunting of the left costophrenic angle is similar to prior . There is bilateral lung base atelectasis and biapical scarring . Heart borders are obscured but appear unchanged . Calcified left hilar node and thoracic dextroscoliosis are stable .
    OUTPUT:
    
Bowel - containing hiatal hernia , similar to prior , with bibasilar atelectasis . Superimposed retrocardiac consolidation can neither be excluded nor confirmed on this exam .