• Transnasal endoscopy;
  • unsedated endoscopy;
  • ultrathin endoscope;
  • gastroesophageal reflux disease;
  • Barrett's esophagus;
  • Level of Evidence: 4



Asymptomatic subjects volunteering for research studies are generally stratified as healthy based on a questionnaire, medical interviewing, and physical examination. The aim of this study was to evaluate the prevalence of upper gastrointestinal (GI) abnormalities in healthy asymptomatic volunteers using unsedated transnasal esophagogastroduodenoscopy (T-EGD) with an ultrathin endoscope as an additional screening tool.

Study Design:

A prospective study from one academic medical center with extensive experience in T-EGD.


Consecutive 150 subjects volunteering for research studies were initially screened by using a gastroesophageal reflux disease (GERD) questionnaire, interviewing, and examination. Based on these, they were stratified as healthy asymptomatic volunteers or with GERD. Unsedated T-EGD was then performed by a faculty member who was blinded to the results of the initial assessment.


On initial assessment using GERD questionnaire, medical interviewing, and physical examination, of the total 150 consecutive research volunteers, 83 (average age 33 ± 16 years; 46 females, 37 males) subjects were healthy asymptomatic volunteers and 67 (average age 36 ± 15 years; 35 females, 32 males) had symptoms of GERD. On T-EGD, GI pathology was found in 15 of 83 (18%) healthy asymptomatic volunteers as compared to 24 of 67 (36%) stratified as having GERD (P < .01). The esophageal abnormalities found in healthy asymptomatic volunteers were esophagitis (13.3%), Barrett's esophagus (2.4%), hiatus hernia (2.4%), and gastritis (2.4%).


A small but significant number of asymptomatic subjects have abnormal upper GI findings. Hence, transnasal unsedated endoscopy can be considered as a screening tool to stratify subjects as healthy, especially when considering them for research studies. Laryngoscope, 2012