Optical coherence tomography of the esophagus and proximal stomach in health and disease

OBJECTIVE: Surveillance of Barrett's esophagus is problematic, as high-grad e dysplasia cannot be recognized endoscopically. Endoscopic ultrasound lack s the resolution to detect high-grade dysplasia. Optical coherence tomograp hy (OCT) employs infrared light reflectance to provide in vivo tissue image s at resolution far superior to endoscopic ultrasound, nearly at the level of histology. We have developed a catheter-based system well suited for stu dy of the GI tract. The purpose of this study was to test this catheter-bas ed OCT system and characterize the OCT appearance of normal squamous mucosa , gastric cardia, Barrett's esophagus, and carcinoma. METHODS: The OCT catheter was passed through the operating channel of the e ndoscope and placed in contact with the esophageal mucosa. Image acquisitio n occurred in apt, proximately 3 s. OCT images were correlated with biopsy and/or resection specimens. RESULTS: OCT was used to construct 477 images of the esophagus and stomach in 69 patients. There were unique, distinct OCT appearances of squamous muc osa, gastric cardia, Barrett's esophagus, and carcinoma. Further, these OCT images were accurately recognized by observers unaware of their site of or igin. CONCLUSIONS: OCT provides a highly detailed view of the GI wall, with clear delineation of a multiple layered structure. It is able to distinguish squ amous mucosa, gastric cardia, Barrett's esophagus, and cancer. This techniq ue holds great potential as an adjunct to the surveillance of patients with Barrett's esophagus, ulcerative pancolitis, and other premalignant conditi ons. (Am J Gastroenterol 2001; 96:2633-2639. (C) 2001 by Am. Coll. of Gastr oenterology).