DIAGNOSIS OF ESOPHAGEAL DISEASES THROUGH ELETRONIC LINEAR ARRAY ENDOSCOPIC ULTRASONOGRAPHY

Abstract

Under supervision of Machida Seisakusho Company and Toshiba Medical Company, an improvement of endoscopic ultrasonography was achieved and its usefulness in the esophageal diseases was also assessed. In fundamental studies, seven layers in the esophageal wall were visualized in the surgical specimen placed in air-free water. A clear correspondence was observed among the seven layers and the layers of the esophageal wall, as follows : mucosa-first and second layers ; submucosa- third layer ; muscularis propria-from the fourth to the sixth layer and, adventitia-seventh layer. Besides, the visualization of lymphnodes about 5 mm in the largest diameter became also possible : However, it was difficult to identify whether lymphnodes were metastatic or not. In the clinical cases a diagnostic rate of the depth of invasion of esophageal cancer was 83.3%. An improvement of the visualization rate of lymphnode over 5 mm in the largest diameter was made from 27.6% in the early period to 57.9% in the late period. Moreover, the diagnostic rate of existence of lymphnodes over 5 mm in the largest diameter was improved from 52.6% in the early period to 79.1% in the late period. Furthermore, this performance was extremely useful in the differential diagnosis among the submucosal tumors as well as the external compressions of the esophagus. It is concluded that endoscopic ultrasonography would become a helpful and inevitable diagnostic method in the near future.