Related Experiment Video
Updated: Mar 16, 2026

Simultaneous Laryngopharyngeal and Conventional Esophageal pH Monitoring
Published on: December 14, 2020
Esophageal Mucosal Impedance Pattern is Distinct in Patients With Extraesophageal Reflux Symptoms and Pathologic Acid
Robert T Kavitt1, Pooja Lal2, Elif Saritas Yuksel3
1Section of Gastroenterology, Hepatology, and Nutrition, University of Chicago, Chicago, Illinois.
Objectives/Study Design:
Current diagnostic tests for gastroesophageal reflux disease (GERD) do not consistently measure chronicity of reflux. Mucosal impedance (MI) is a minimally invasive measurement to assess esophageal conductivity changes due to GERD. We aimed to investigate MI pattern in patients with symptoms of extraesophageal reflux (EER) in a prospective longitudinal cohort study.
Methods:
Patients with potential symptoms of EER undergoing esophagogastroduodenoscopy (EGD) with wireless pH monitoring were studied. Participants included those with erosive esophagitis (E+), normal EGD/abnormal pH (E-/pH+), and normal EGD/normal pH (E-/pH-). MI was measured from the site of injury in patients with E+, as well as at 2, 5, and 10 cm above the squamocolumnar junction (SCJ) in all participants.
Results:
Forty-one patients with symptoms of EER were studied. MI measurements at 2 cm above the SCJ were significantly (P = 0.04) different among the three groups, with MI lowest for E+ and greatest for E-/pH- patients. Although not statistically significant, there is a graded increase in median (interquartile range) MI axially along the esophagus at 5 cm (P = 0.20) and at 10 cm (P = 0.27) above the SCJ, with those with reflux (E+ and E-/pH+) having a lower MI than those without.
Conclusions:
Patients with symptoms of EER and evidence of acid reflux have an MI lower than those without at 2 cm above the SCJ, with a trend at 5 cm and 10 cm as well. MI may be a tool to assess presence of GERD in patients presenting with EER symptoms.
Related Concept Videos
Gastroesophageal Reflux Disease I: Meaning and Pathophysiology
Gastroesophageal Reflux Disease II: Clinical Features and Management
Clinical Manifestations
GERD presents itself in a multitude of ways, with symptoms varying from person to person. The hallmark symptoms are...
Barrett Esophagus-II: Clinical Manifestations and Management
To diagnose Barrett's esophagus, healthcare providers often recommend an endoscopy for those showing symptoms of acid reflux. The procedure...
Barrett Esophagus-I: Introduction
This constant acid exposure transforms the esophagus's pink mucosal lining (stratified squamous epithelium) into a type of lining more...
Esophageal Strictures-II: Clinical Features and Management
Healthcare providers should gather a comprehensive medical history and conduct a physical examination for diagnosis. If esophageal stricture is...
Esophageal Strictures-I: Introduction
Etiology
The primary cause of esophageal strictures is long-standing gastroesophageal reflux disease (GERD), accounting for about 70 to 80% of adult cases. Chronic acid reflux can lead to injury and scarring of the esophageal lining, culminating in...

