The purpose of this research is to test the feasibility, sensitivity, and specificity of the marking Optical Frequency Domain Imaging (OFDI) capsule for diagnosing Barrett's Esophagus (BE).

A total of 130 participants scheduled to undergo esophagogastroduodenoscopy (EGD) will be asked to swallow the OFDI capsule while being unsedated. The capsule is attached to a tether that allows the capsule operator to navigate the capsule as it progresses down the esophagus using natural propulsion called peristalsis as well as to bring it back up to pulled out of the mouth when the procedure is done.

OFDI real-time images will be used for targeting of the region to be marked. Once in position, two cautery marks will be made to only the superficial layers of the esophageal mucosa. Following cautery marking, the capsule will be lowered in the esophagus and marked regions of interest will be reimaged for confirmation of the placement of potential cautery marks.

Immediately following the completion of the experimental procedure, the standard of care with the performance of the surveillance endoscopy will be performed. Images obtained by the OFDI capsule will be compared to the images obtained by the clinical endoscopy and histology.

Inclusion Criteria:

• Patients must be undergoing an EGD.
• Patients must be over the age of 18.
• Patients must be able to give informed consent.

Exclusion Criteria:

• Patients who are on anti-platelet medications or anti-coagulation medications, and NSAIDS at the time of procedure.
• OR patients with a history of hemostasis disorders.
• OR patients with esophageal strictures.