Endoscopic Congo red test during proximal gastric vagotomy.

Although proximal gastric vagotomy is widely performed as an elective treatment for duodenal ulcer, the incidence of recurrent ulcer is troublesome. There are several theories to explain recurrent ulcers, and important technical steps should be considered when performing proximal gastric vagotomy. The use of an intraoperative test may allow more accurate performance of the operation and more complete vagotomy of the parietal cell mass. This report describes the use of the endoscopic Congo red test in patients during proximal gastric vagotomy. The test allows rapid and accurate mapping of areas of the stomach with intact vagus and secretory nerves after operative vagotomy, and can be repeated several times if necessary to verify completion of the vagotomy. The use of universally available equipment and the potential for intraoperative and postoperative use are other attractive features of the test. Use of the endoscopic Congo red test provides physiologic evidence that vagus secretory nerve fibers traverse the right and left gastroepiploic nerves, leading us to believe that the gastroepiploic nerves should be routinely divided during proximal gastric vagotomy. In patients with recurrent duodenal ulcer requiring reoperation, the endoscopic Congo red test allows preoperative demonstration of the site of the intact vagal nerve trunks. The endoscopic Congo red test deserves further investigation and wider application during operations for chronic duodenal ulcer.