Use of multichannel intraluminal impedance to document proximal esophageal and pharyngeal nonacidic reflux episodes

Recent studies in adults and children suggest that combined multichannel intraluminal impedance and pH measurement (MII-pH) has the potential to become the new “gold standard” for gastroesophageal reflux testing. In combined MII-pH, reflux is detected by changes in resistance to alternating current induced by the presence of intraluminal materials with different conductivities, and is characterized as acid or nonacid reflux based on concomitant pH measurements. Proximal distribution and duration of nonacid reflux events, predominantly in postprandial periods and during acid-suppressive therapy, can now be quantified. The ability to associate symptoms with nonacid reflux events will help guide therapy in select groups of patients, such as patients with ongoing symptoms on acid-suppressive therapy as well as in the pediatric population.