Abstract
Endoscopic ultrasonography (EUS) was examined in 80 patients with pancreatic and biliary diseases including 33 cases of tumorous lesions, and the diagnostic accuracy of the method was examined especially in the small lesions of the pancreato-biliary tract. Ultrasonic scanning was made through the wall of the digestive tract using an echo-endoscope (Sector type, Olympus and Aloka Co. Ltd.) mainly with a balloon attached to the end of the scanner (balloon method). The head of the pancreas and the biliary tract were scanned via the postbulbar region or the descending portion of the duodenum, and the body and tail of the pancreas via the posterior wall of the gastric body. Clear ultrasonographic images of the lesions were obtained in all 33 patients with pancreatic and biliary tumors including 13 small lesions with diameters of 30 mm or less (10 of them with diameters of 20 mm or less). These small lesions included 11 malignant tumors (4 in the pancreas, 4 in the biliary tract, and in the papilla vater) and 2 benign tumors (a focal pancreatitis and an adenoma in the common bile duct). The high demonstrability of EUS was recognized by comparison with other body imaging diagnostics such as US, ERCP, CT and angiography. With improvement of the scope and establishment of appropriate scanning technique, this method is expected to be effective in the diagnosis of small pancreatic and biliary tumors.
