Can high resolution manometry parameters for achalasia be obtained by conventional manometry?

Abstract

High resolution manometry (HRM) is a new technology that made important contributions to the field of gastrointestinal physiology. HRM showed clear advantages over conventional manometry and it allowed the creation of different manometric parameters. On the other side, conventional manometry is still wild available. It must be better studied if the new technology made possible the creation and study of these parameters or if they were always there but the colorful intuitive panoramic view of the peristalsis from the pharynx to the stomach HRM allowed the human eyes to distinguish subtle parameters unknown or uncomprehend so far and if HRM parameters can be reliably obtained by conventional manometry and data from conventional manometry still can be accepted in achalasia studies. Conventional manometry relied solely on the residual pressure to evaluate lower esophageal sphincter (LES) relaxation while HRM can obtain the Integrated Relaxation Pressure. Esophageal body HRM parameters defines achalasia subtypes, the Chicago classification, based on esophageal pressurization after swallows. The characterization of each subtype is very intuitive by HRM but also easy by conventional manometry since only wave amplitudes need to be measured. In conclusion, conventional manometry is still valuable to classify achalasia according to the Chicago classification. HRM permits a better study of the LES.

Keywords: Achalasia; Chicago classification; Conventional manometry; Esophageal body; Esophagus; High resolution manometry; Lower esophageal sphincter.

Figure 1

Example of high resolution parameters identifiable at the conventional manometry. A: The peristaltic gap at transition zone (change from striated to smooth muscle in the proximal esophagus - arrow) has been fully explored with high resolution manometry[11] but it was well-known and identifiable as low amplitude waves at the proximal esophagus (arrow), although the clinical significance not comprehended, by conventional manometrists (B)[12]; C: The contractile deceleration point (CDP) represents the inflexion point in the contractile front propagation velocity in the distal esophagus representing the motility of the ampulla (arrow). Conventional manometry neglected time and privileged only amplitudes. A progressive latter onset of the distal wave (CDP) can be noticed from 3 to 1 cm above the lower esophageal sphincter upper border (D-F).

Figure 2

Chicago classification subtypes at the light of high resolution manometry (left) and conventional manometry (right). Type I (no distal pressurization), type II (panesophageal pressurization), and type III (premature spastic contractions).