[Esophageal manometry: methods of investigation and interpretation of results]

Standard manometry is still today the method of choice for investigating motor disorders of the esophagus. Fundamental elements in executing the test are suitable equipment, an execution technique following well established protocols and the adoption of univocal criteria for interpreting the results. In fact it is essential to use low compliance pneumo-hydraulic pumps and to perform the test in distinct steps to separately evaluate the features of the sphincter and the peristaltic activity of the esophageal body. Newly introduced technology (computerized analysis) authorizes an objective analysis of the tracing and the measurement of novel parameters, making it necessary however to re-evaluate the parameters of normalcy in the asymptomatic population. The manometric features of the lower esophageal sphincter, which define its competence (mean pressure at the point of respiratory inversion, abdominal length, total length), are probably better expressed by the mean pressure of the entire LES, by the area under the curve and by the Vector Volume. As far as motility of the esophageal body is concerned, computerized manometry provides for a more precise definition of the maximum amplitude of the esophageal contractions and an objective measure of their duration.