Airway obstruction in achalasia

A man with a mediastinal mass shadow detected on chest roentgenogram was diagnosed as having achalasia by barium swallowing study. Megaesophagus caused by achalasia produced airway obstruction. Maximum expiratory-inspiratory flow volume curve identified that peak flow rate decreased in early expiration, and the ratio of expired to inspired flow at 50 percent of vital capacity was below 0.9, aggravated by 250 ml water intake. Deformation of the tracheal shape was proved easily.