Three-dimensional endoscopic ultrasonography of lesions of the upper gastrointestinal tract using a radial-linear switchable thin ultrasound probe

Background: The objective of three-dimensional (3-D) endoscopic ultrasonogr aphy (EUS) is to recognize lesions stereoscopically. Methods and Results: We investigated a total of 43 legions in the upper gas trointestinal (GI) tract by regenerating 3-D images in eight cases of oesop hageal cancer, two cases of oesophageal submucosal tumour, two oesophageal varices, two cases of achalasia, 27 gastric cancers, one gastric carcinoid, and one duodenal submucosal tumour. Using a prototype system (Fujinon, Omi ya, Japan), we reconstructed 3-D images from conventional EUS images taken by a thin ultrasound probe (Sonoprobe, SP-701, Fujinon) having a radial-lin ear scanning mode. The basic 3-D images could be obtained in a short period during EUS performed using the conventional thin-ultrasound probe. The acc eptable quality level of the reconstructed 3-D images was 37% (57% in the o esophagus, 25% in the: stomach and 100% in the duodenum). Deterioration of 3-D images was due to a wobbling of linear scanning mainly caused by perist alsis of the GI tract, cardiac impulses, and respiration. Conclusions: Our study has proved that the simple and speedy 3-D display sy stem built using the existing linear-radial switchable probe is easily appl icable to clinical cases. (C) 1999 Blackwell Science Asia Pry Ltd.