Conventional manometry and high resolution manometry with esophageal pressure topography

Manometry quantifies intraluminal esophageal and LES pressure during swallowing to detect abnormalities of peristalsis and sphincter relaxation. Conventional manometry achieved this with relatively few pressure sensors (red dots in schematic on the left and red lines in the center panel). Hence data from conventional manometry can only be accurately displayed as pressure versus time plots as in the center panel with large gaps in the esophageal lumen between pressure recording sites. High resolution manometry fills these gaps with a multitude of closely spaced pressure sensors (blue dots in the schematic on the left and white lines in the center panel). Alternatively, high resolution manometry can be displayed as a "Clouse plot" in esophageal pressure topography as in the right panel with pressure plotted as a continuum, interpolating values between the closely spaced sensors and displaying the pressure magnitude by color. When displayed in pressure topographic, stereotypic features of the topographic architecture of the peristaltic contraction become evident, labeled as the 1st, 2nd, 3rd, and 4th contractile segments and the proximal, middle, and distal pressure troughs. The 4th contractile segment is the LES. The onset of the swallow, timed by upper sphincter relaxation, is indicated by the vertical dotted line.