WHILE gastroscopy is one of the oldest methods of examination of the stomach, its limitations were so great that it was of little clinical help until the advent of the flexible gastroscope, with the pioneering work of Schindler. In the hands of one skilled in the use of such an instrument, gastroscopic examination now has become an important addition to the armamentarium of the gastroenterologist and of every one interested in gastric lesions.
In spite of its proved value, however, gastroscopy still possesses two definite defects. One is that a small but sometimes important area of the stomach cannot be visualized by the gastroscope, and the other is that diagnosis is almost completely established by topographic observation only. For many fairly well advanced lesions, such topographic observation is adequate to establish a diagnosis; as a matter of fact, in many such cases gastroscopic examination is hardly necessary for an understanding