The Capability of Three Dimensional Display during Endoscopic Ultrasonography

Abstract: Endoscopic ultrasonography (EUS) has been found to be useful in determining the depth of invasion of gastric cancer, the diagnosis of submucosal tumors and extramural compressions. A problem with this procedure is that it is difficult to determine stereoscopically the relative position of the lesion as a whole, even though EUS may be an excellent diagnostic tool for determining tomographies. In this paper, we made three-dimensional displays of EUS images using a personal computer to facilitate understanding of the relative anatomical positions of the lesions. During EUS examination, the distance from the incisors was acccurately measured, and the EUS image was recorded on U-matic tape. To measure the distance from the incisors, we devised a new instrument for measuring the endoscopic insertion length. The recorded tape was edited for input into the computer. The soft-ware for the three-dimensional display program was made by Photoron. Inc. A patient with esophageal cancer, a patient with a common bile duct stone and a patient with pancreatic cancer are presented as examples for definition of the relationship with the surrounding organs. A patient with a gastric ulcer is used as an example to clarify the pathological structure of the lesions. Using our method on these patients, it was easy to obtain a stereograph and to obtain complete images of the lesions. EUS was available for three -dimensional displays of the lesions in the gastrointestinal tract and in the surrounding area, and this has clinical significance.