ABSTRACT
Virtual endoscopy (VE), three-dimensional endoscopic ultrasonography(3-DEUS) and three-dimensional ultrasonography(3D-US) have been utilized for three-dimensional medical images of upper gastrointestinal lesions. VE images are similar to endoscopic images. But because the detection rate of early gastric cancers is from 39.6% to 78%, it is difficult to use for the screening of gastric lesions now. 3-DEUS has been used for assessment of depth of cancerous invasion or treatment for esophageal and gastric cancer. Accuracy of cancerous invasion has been improved by 3-DEUS because both radial images and lineal images are able to be observed simultaneously. One of benefit in 3D-US is not invasive. These methods are thought to be improved and to be popularized.