24-hour esophageal multichannel intraluminal impedance and pH monitoring

Monitoring of esophageal impedance is a technique for determining the physical characteris- tics (liquid, gas, or mixed) of refluxate, while impedance monitoring combined with pH recording makes it possible to assess the acidity of reflux(acid or non-acid). Assessment is usually performed by the total acid exposure time (%time pH4) and symptom-reflux asso- ciations including acidic and non-acidic reflux. This monitoring is quite useful for evaluation of proton pump inhibitor-resistant gastroesophageal reflux disease or non-erosive reflux disease. When normal acid exposure time and significant symptom-reflux associations are observed, a patient should be diagnosed as having hypersensitive esophagus. When normal acid exposure time and no significant symptom-reflux associations are observed, a patient should be diagnosed as having functional heartburn. Therefore, the result makes it possible to decide treatment strategy.