Endoscopic sonography of the upper gastrointestinal tract.

Endoscopic sonography was used to examine the upper gastrointestinal tract of 550 patients referred for evaluation of abnormal findings seen on conventional endoscopy, upper gastrointestinal series, and CT. This essay illustrates the potential uses and limitations of this technique. Special emphasis has been given to the use of landmarks to facilitate orientation of the transducer in both the esophagus and stomach. Specific examples demonstrate involvement of individual layers of the bowel wall in both benign and malignant processes. It is stressed that this is a combined procedure requiring both an endoscopist and a radiologist. Endoscopic sonography is a valuable new technology with substantial potential in the evaluation of the upper gastrointestinal tract.