? The incidence of adinocarcinoma of the distal esophagus has risen dramatically in the U.S. in the past 40 years. Most of these cases are thought to have arisen from a potentially premalignent condition; Barrett's Esophagus (BE). Various endoscopic techniques for ablating the esophageal mucosa have been explored in both humans and animal models. So far none of these techniques has emerged as fully satisfactory. Complications such as stricture, perforation, incomplete ablation, or the requirement for exceptional endoscopic surgical skills have plagued these techniques. Water-jet surgical scalpels are well known for their selective resection of various tissues while conserving underlying vasculature. Unfortunately, these devices are rigid with relatively large cross sections that are not compatible with endoscopic procedures. We propose an approach based on endoscopically deployed high pressure liquid-jet technology that is preferentially selective for columnar esophageal mucosa. Previously conducted ex-vivo experiments have demonstrated that liquid-jet cathers can eliminate mucousal linings in animal gall bladder and small intestine without significant injury to the underlying collagen rich submucosal layer. Similar results are anticipated in this investigation. The proposed research outlines the design, development, and testing of a high-pressure, liquid-jet catheter on human esophagestomy tissue with BE. In a second portion of the study; endoscopic mucosal ablation using the water-jet in an anatomical environment similar to the human esophagus (swine model) will be attempted. ? ? ?