Narrow Band Imaging Useful for Diagnosing Nonerosive Reflux Disease

African American doctor talking to patient in office
Researchers assessed the accuracy of narrow band imaging for patients with nonerosive reflux disease vs control individuals.

Ridge-villous patterns on narrow band imaging (NBI) correlated with exposure time to acid and improved following proton pump inhibitor (PPI) treatment in patients with nonerosive reflux disease (NERD), according to study findings published in Gastrointestinal Endoscopy.

Researchers conducted an 8-week randomized, placebo-controlled trial ( Identifier: NCT02081404) at the Kansas City Veteran’s Affairs Medical Center in the United States and Nottingham University Hospital in the United Kingdom.

Following esophagogastroduodenoscopy (EGD) and biopsy screening, the researchers included 21 patients with NERD compared with 21 control participants who answered negatively to reflux questions on the Gastroesophageal Reflux Disorder Questionnaire (GERDQ). The investigators subdivided the 21 patients with NERD — 10 receiving 40 mg of esomeprazole daily and 11 receiving a placebo.

Prior to PPI treatment, NBI frequently identified ridge-villous patterns, micro-erosions, increased vascularity at the squamocolumnar junction (SCJ), and intrapapillary capillary loop (IPCL) tortuosity and dilation in patients with NERD.

Ridge-villous patterns demonstrated a 62% sensitivity and 81% specificity for NERD. Micro-erosions maintained the highest specificity of 95%, despite a low sensitivity of 29%. Increased vascularity at SCJ had a 90% specificity and 38% sensitivity, and IPCL tortuosity and dilation both demonstrated specificities of 86% and sensitivities of 79%.

Combining the features of IPCL tortuosity, ridge-villous patterns, and micro-erosions resulted in the highest specificity of 86% with a moderate sensitivity of 60% for NERD diagnosis.

Following PPI treatment, the most distinctive NBI finding was the resolution of micro-erosions in 66% of patients with NERD compared with 0% in the placebo group (P =.047). Ridge-villous patterns also significantly resolved on NBI after treatment (P =.02).

All 10 patients in the PPI treatment group expressed symptom improvements on their GERDQ scores compared with 7 of 11 patients in the placebo group (P =.034). Improvements in NBI for ridge-villous patterns did not correlate with improved GERDQ scores (P =.67), while micro-erosions moderately correlated (P =.02). Concurrent ridge-villous patterns and micro-erosions did not correlate with changes in GERDQ scores (P =.74).

Acid exposure time averaged 11.3% in the NERD group and 2.88% in the control group. Of the many NBI features indicative of NERD, only ridge-villous patterns correlated with abnormal acid exposure times (P =.004), suggesting a potential use for this imaging result as a marker for NERD diagnosis.

“NBI at initial endoscopy can identify NERD subjects with high specificity that can obviate the need for additional investigations and reduce unnecessary drug costs,” the study authors noted. “In particular, the ridge-villous pattern feature can be used as a surrogate marker for acid reflux testing for diagnosis of NERD. Narrow band imaging has a positive role in diagnosing nonerosive reflux disease and identify[ing] subjects who would benefit from acid suppression therapy.”

Small sample size and subjectivity of GERDQ scores potentially contributed to lack of correlation between mucosal changes and GERDQ scores at baseline and following treatment. Another study limitation included the short trial duration, considering that patients with GERD typically experience a longer duration of symptoms (>8 weeks).


Desai M, Srinivasan S, Sundaram S, et al. Narrow band imaging for diagnosis of non-erosive reflux disease: An international, multicenter, randomized controlled trial. Gastrointest Endosc. Published online April 26, 2022. doi:10.1016/j.gie.2022.04.020