['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.', '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.', 'Forty-one patients with symptoms of EER were studied. MI measurements at 2\u2009cm above the SCJ were significantly (P\u2009=\u20090.04) 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\u2009cm (P\u2009=\u20090.20) and at 10\u2009cm (P\u2009=\u20090.27) above the SCJ, with those with reflux (E+ and E-/pH+) having a lower MI than those without.'] Is esophageal Mucosal Impedance Pattern Distinct in Patients With Extraesophageal Reflux Symptoms and Pathologic Acid Reflux?