In a former article,1 we demonstrated the importance of roentgen examination, following a definite scheme, when there is a question of congenital hypertrophic stenosis of the pylorus. The purpose is to demonstrate the pyloric canal in its longest dimension, which in normal children averages only from 1 to 2 mm.
In order to determine the proper treatment it is also necessary to ascertain the retention of barium sulphate in the stomach. As retention can be entirely absent in one roentgen examination, in the presence of serious hypertrophy of the muscle, it is sometimes necessary to repeat the examination. In a recent publication Voss2 came to the same conclusion. Moreover, he pointed out the sharply marked outline of the pyloric canal in respect to the stomach and the bulbus duodeni. Peristalsis of the pyloric canal is absent, and the bulbus unfolds itself insufficiently. Voss took little account of the