Esophageal function tests in clinical practice: a review

Diseases of esophagus are common in gastroenterology practice. Improvement in diagnosis and better understanding in pathophysiology of these diseases have been possible recently of due to advancement in technology. Advancement made in the field of computer softwares is another key development aiding further improvement in these instruments. In this article, we review techniques, interpretation and clinical utility of various tests of esophageal function with special reference to manometry, ambulatory pH and impedance monitoring. Esophageal manometry is simple to perform. Recent, availability of commercial user-friendly software has made analysis of recorded data easy. High resolution spatio-temporal manometry is advancement over conventional manometry. Manometry is a useful tool for diagnosis, followup and research in esophageal motility disorders. Ambulatory 24-h pH metry and impedance monitoring are also easily analyzed by commercially available software. 24-h impedance combined with pH-metry is currently considered as the gold standard for diagnosis of gastroesophageal reflux disease (GERD). All patients with GERD may not require these investigations, but those with atypical symptoms, those refractory to medical treatment and requiring surgery do. Esophageal transit study is useful in understanding functional correlates of abnormalities in manometry and is particularly useful during follow up studies and in research.