To date there is no effective way to objectively characterize and predict response to endoscopic dilation of luminal strictures of the GI tract. Endoscopic dilation allows effective remediation of benign esophageal and upper GI tract strictures. Stricture dilation is performed after the stricture diameter is crudely gauged by the endoscopist. Stricture characteristics are based on the severity of symptoms and appearance. A stricture may be graded as mild, moderate, severe and as to whether or not the endoscope is able to traverse the luminal narrowing. By precisely measuring the diameter and length of a stricture, the endoscopist can know exactly what type of dilation is necessary. Benign esophageal strictures may also be refractory to dilation and thus require multiple sessions, prior to achieving successful remediation. The purpose of this study is to investigate the use of a functional luminal imaging probe to characterize benign esophageal luminal strictures before and after dilation and identify predictors of response to therapy. Patients will be evaluated during endoscopy using functional luminal imaging (EndoFLIP; Crospon Medical Devices, Galway,
Ireland) to characterize the geometry of benign luminal esophageal narrowing before and after dilation. The study will include patients with strictures referred for endoscopic dilation for the following indications: radiation induced strictures, peptic strictures, RFA induced strictures, EMR induced strictures, eosinophilic esophagitis, Zenkers diverticulum, and strictures related to surgical anastomoses. In patients with benign refractory esophageal strictures referred for endoluminal prostheses EndoFLIP will be used to characterize the stricture prior to stent placement.