Endoscopic ultrasonography: preliminary experience.

Endoscopic ultrasonography was performed in 30 patients using the prototype ultrasound fiberoptic endoscope (Model GF- UM1 , Olympus Corporation) with the objective of developing technique, assessing instrument performance, and familiarization with the capabilities of endoscopic ultrasonography. Insertion of the instrument was accomplished in all patients. There were no complications. Some difficulty was encountered in maneuvering the instrument through relatively narrow areas of the gastrointestinal tract including the pylorus and apex of the duodenal bulb. Diagnostic upper gastrointestinal endoscopy was performed prior to endoscopic ultrasonography using standard forward viewing endoscopes. A variety of normal anatomic structures were noted. Examinations required from 30 to 45 minutes. Images obtained were sharp and clear, although there was some decrease in resolution with depth of display. The advantages and indications for the procedure are not yet established. The procedure might be considered for special purposes such as examination of the pancreas.