The goal of this study is to test the feasibility and acceptability of tethered capsule Optical Coherence Tomography (OCT) endomicroscopy as a device for population-based screening in the primary care practice environment.

60 healthy volunteers scheduled for a routine primary care visit will be recruited and asked to swallow the OCT capsule while being awake and unsedated. The capsule is attached to a tether which allows the operator to control as well as navigate the capsule as it progresses down the esophagus using natural propulsive force called peristalsis.

As the capsule progresses through the esophagus, multiple images of the esophagus are acquired and later analyzed.

Inclusion Criteria:

• Subjects must be scheduled for non-urgent appointment at primary care practice including annual wellness visits and routine follow-up appointments.
• Subjects must be over the age of 18
• Subjects must be able to give informed consent
• Subjects must have no solid food for 4 hours prior to the procedure, and only clear liquids for 2 hours prior to the procedure.

Exclusion Criteria:

• Subjects with current symptoms of dysphagia
• Subjects with any history of intestinal strictures, prior GI surgery, or history of intestinal Crohn's disease.
• Subjects with current symptoms of fever, nausea or sore throat at the time of the appointment.
• Pregnancy

During the procedure and 10 minutes after

The adverse events were collected systematically for this study. The definition of adverse events is the same as clinicaltrials.gov definition.