Endoscopic sonography is a new approach to visualizing upper gastroint
estinal lesions, The sonographic device, which incorporates a sonograp
hic transducer mounted on a standard fiberoptic endoscope, makes it po
ssible to obtain high-resolution images of mucosal and mural lesions o
f the gastrointestinal tract, as well as of adjacent masses. This tech
nique has substantially improved preoperative staging of esophageal an
d gastric cancers. In addition, high-resolution sonographs of the panc
reas can be obtained without degradation by overlying bowel gas, makin
g identification of small, previously occult lesions of the pancreatic
head possible,We have used endoscopic sonography in staging esophagea
l, gastric, and pancreatic cancers in more than 200 patients, This ess
ay illustrates our experience with this new technique.