ULTRASONIC ESOPHAGOPROBE (PROTOTYPE-1)

Endosonography (ES), which allows the precise differentiation of the layers of the gastrointestinal tract as well as recognition of regional lymph nodes, has taken a central role in the pre-operative TNM staging of gastrointestinal tumors. The accuracy of ES in the locoregional staging of esophageal and gastric carcinomas is in the order of 80 to 90%.^ However, the assessment of stenosing carcinomas has been hitherto limited by the relatively large outer diameter (11 to 13 mm) of conventional echoendoscopes with oblique optics. Such cases require extensive dilation (usually to a minimum of 45 French), which is not always feasible and may lead to perforation. The risk of perforation is further augmented by the practically blind insertion of the echoendoscope with its blunt, rigid tip. Stenosing carcinomas involving the cervical esophagus are particularly problematic. To reduce the procedural risk and increase the number of cases amenable to echoendoscopic evaluation, we devised a new thin-diameter echoendoscope with a tapered tip analogous to a bougie. © 1992, American Society for Gastrointestinal Endoscopy. All rights reserved.