[Endoscopic ultrasonography of the digestive tract].

Endoscopic ultrasonography of the digestive tract provides for a precise ultrasonic study of the accessible gastrointestinal walls (oesophagus, stomach, duodenum, rectum) and, through these walls, of the adjacent organs (lymph node clusters, posterior mediastinum, pancreas, extrahepatic biliary ducts and perirectal environment). This method is better than computerized tomography to evaluate the local and regional extension of oesophageal and cardial carcinomas producing little or no stenosis and of rectal carcinomas. It is the examination of choice to detect a perianastomotic recurrence of these cancers and to evaluate submucosal tumours of the digestive tract and thick fold stomach diseases. Its use in the aetiological diagnosis of obstacles in the biliary tract and in the pretherapeutic assessment of pancreatic and biliary tract cancers seems to be very promising.