Experimental investigations into the possibility of differentiating early from invasive carcinoma of the stomach by means of ultrasound.

Using high-resolution ultrasound such as is employed, for example, in endoscopic ultrasonography, the walls of hollow organs are visualized as layered structures. The correlation of these "acoustic layers" with the histological layers, is of particular interest for the staging of early malignant lesions. Both clinically and experimentally, we made an attempt to determine the extent to which, at a transducer frequency of 7 MHz, such a correlation is possible. Our investigations show that, although reflection phenomena can mimic and "overlap" anatomical layers, the important boundary between the submucosa and the muscularis propria is principially identifiable.