During routine esophagogastroduodenoscopy (EGD), consented study participants will have a series of three (3) custom mucosal impedance (MI) catheters with an axial array of sensors positioned along the mucosal wall to directly measure mucosal impedance at various intervals. Each catheter will be manually guided by the physician through the working channel of the endoscope until the sensored tip is visible through the scope camera. The physician will place the sensored rings directly on the mucosa along the lumen. To obtain evaluable data, the sensors must remain in contact with the mucosa at each point for 5 seconds after a stable impedance reading has been captured. This process will be repeated for each of the three prototype catheters in each consented patient in order to determine the optimal catheter/sensor design. The catheters will be attached to a channeled feed that will record measurements on a dedicated computer.
