The investigators are seeking healthy adult participants 18-60 years and healthy pregnant women in their 2nd trimester of pregnancy for a research study to assess a new imaging device. The Tearney Laboratory at the Wellman Center for Photomedicine at Massachusetts General Hospital is developing high-resolution imaging devices that can be used to improve diagnostics in gastrointestinal diseases.

The investigators have developed a device that can image the duodenum (the first part of the small intestine). The device consists of a thin, flexible tube with a small internal camera inside of it that takes high-resolution images of the gastrointestinal tract. The device will be introduced through the nose and then advanced into the stomach and duodenum. Participant tolerability, imaging quality and the optimal imaging technique will be evaluated. The results of this study will be used as the basis for a larger study to be conducted at the Aga Khan University Hospital in Pakistan where subjects with suspected or diagnosed EED will be imaged.

Inclusion Criteria:

• Healthy participants
• Participants who are in their 2nd trimester of pregnancy
• Participant must be 18-60 years of age
• Participant must be able to consent to the procedure.
• Participant must fast (no solid food) for at least 8 hours and have no liquids within 2 hours prior to the procedure.

Exclusion Criteria:

• Participants with a history of upper respiratory disease or surgery
• Pregnant women with high-risk pregnancies such as history of: hyperemesis gravidarum, HIV, severe anemia or any other high-risk pregnancy conditions at the discretion of the subject's physician and the PI
• Participants with a history of upper gastrointestinal surgery
• Pregnant women with Type 1 diabetes
• Pregnant women with Type 2 diabetes on medication and gestational diabetes requiring medication
• Pregnant women with gestational thrombocytopenia
• Participants with upper respiratory infection at least 7 days prior to the procedure
• Pariticipants with any contraindications to the placement of the NJ tube including deviated septum or any other anatomical abnormalities of the nasopharynx or upper gastrointestinal region, history of trans-sphenoidal surgery, facial or cranial trauma and fractures, chronic sinusitis, esophageal strictures, varices etc.
• Participants on medications that delay gastric emptying.
• Participants on drugs which impair clotting like anticoagulants and antiplatelet drugs, NSAIDS, history of bleeding disorders.
• Participants using nasal steroids or any steroids for environmental allergies.