High Definition White Light Endoscopy and Narrow Band Imaging for the Assessment of Barrett's Disease After Endoscopic Therapy

Inclusion Criteria:

* Age 18 years and older
* Patients with Barrett's esophagus (BE) dysplasia as the original indication for treatment
* Undergoing any type of endoscopic BE resection or ablation treatment including RFA, cryotherapy, photodynamic therapy, or EMR, or combinations of these.
* \<1cm of circumferential, peninsular, or island-type BE on prior endoscopy or ablation
* Ability to provide written, informed consent

Deferral Criteria: This category is for patients in two specific situations, 1) Erosive esophagitis, and, 2) presence of a nodule suspicious for the presence of neoplasia.

1. Erosive esophagitis: patients found to have erosive esophagitis, will be deferred for up to 3 months from their Index study procedure, to permit more aggressive medical therapy to heal the erosive esophagitis. After healing, the Index study procedure will be performed up to 3 months later, and the follow-up endoscopy (and study closure) performed 3 to 6 months after that (total of no more than 9 months).
2. Presence of nodule suspicious for neoplasia: for patients found to have such nodular lesions, the Index study procedure will be deferred for 3 months, while Endoscopic Mucosal Resection is performed and subsequently heals.

Note: Only one deferral per patient is permitted, and this one deferral is allowed only for these specific criteria. The end of the study will be defined by the time of follow-up of the last patient who was not deferred; any deferred patients who have not completed follow-up procedures by that time, may miss their follow-up visit as part of the study. (This is to prevent the possibility of delaying the close of the study due to deferral of a procedure late in the study.)

Exclusion Criteria:

* Current participation in another clinical study
* Complete eradication of BE documented by biopsies in 3 or more previous endoscopic procedures performed after resection/ablation
* Inability to obtain biopsies due to anticoagulation, varices, etc.
* Pregnancy
* Worse than Grade C erosive esophagitis
* Less than 3 weeks from previous endoscopy with biopsy or 6 weeks from previous endoscopic therapy (ablation or resection).