382 Esophageal Mucosal Impedance Measurement During Endoscopy: A New Approach to Diagnosis and Confirmation of Complete Remission of Intestinal Metaplasia Following Radiofrequency Ablation in Barrett’s Esophagus

Abstract

INTRODUCTION: Mucosal impedance (MI), measured with a specialized balloon catheter at the time of upper endoscopy reveals a distinct pattern within the esophagus in patients with eosinophilic esophagitis and GERD. This novel technology may also be able to identify a unique profile in Barrett’s esophagus (BE) and confirm Endoscopic Complete Remission of Intestinal Metaplasia (ECRIM) following Radiofrequency energy ablation (RFA). AIM: Explore utility of MI in identification of BE and confirmation of ECRIM following RFA. METHODS: Patients (pts) with endoscopic and biopsy proven BE, most dysplasia undergoing RFA were prospectively enrolled. All were maintained on BID PPI. EGD noted top of gastric folds, SCJ, Prague criteria, hernia size and presence of nodules. Pts with nodular disease were excluded. RFA was performed per standard protocol and repeated until ECRIM achieved. Measurements were obtained with an MI balloon (Diversatek Healthcare, CO) 10 cm x 5 mm with two axial arrays of 10 sensors, throughout the entire BE segment and 5 cm above at pre-ablation EGD and following achieving ECRIM. At ECRIM endoscopic surveillance biopsies (q 1 cm; 4 quadrant) and WATS brushings were obtained to confirm CRIM. RESULTS: 16 pts 11M/5F, ages 26-71 years, all Caucasian were enrolled. BE length from 1-15 cm. (adenoca 1, LGD 5, HGD 5, indefinite1, Non dysplastic 4. To date, 7 pts have been studied prior to the initial RFA ablation and at ECRIM. 2 pts were studied only at end of RFA with ECRIM. 7 are in active treatment. MI measured within the BE segment ranged from 350-980 ohms pre RFA. (Normal >2500, EoE, GERD >1000). Post RFA MI measurements ranged from 1800- >5000 ohms. 5/7 pts that achieved ECRIM had normalization of the MI pattern visualized (all values >2500). The 2 pts that did not achieve normalization of the MI pattern demonstrated MI values consistent with inflammation in squamous tissue but no values suggestive of BE. Pathology confirmed absence of IM in all 9 pts. CONCLUSION/SUMMARY: 1) BE exhibits MI consistently < 500 ohms and always below 1000 ohms, a unique MI profile not evident in GERD or EoE. 2) In pts who achieved ECRIM and biopsy and WATS proven CRIM following RFA ablation, the neosquamous esophageal mucosa exhibits a MI pattern similar to normal native squamous epithelium. Balloon catheter MI measurements can reliably identify BE epithelium and may be a valuable tool in assessment of post-RFA reversion to neosquamous epithielium and therefore successful BE ablation.