Читать книгу The Esophagus - Группа авторов - Страница 131

Secondary peristalsis originates in the esophagus in response to local sensory stimulation, such as from retained food not cleared by the primary wave or from refluxed acid. This peristaltic wave is similar to primary peristalsis but begins in the esophagus at or above the level of the stimulus. However, distention high in the esophagus may at times initiate the process at the pharyngeal stage [184].

Figure 5.10 Esophageal peristalsis: relationship between videofluoroscopic, manometric, impedance, and topographic representations. (A) Depiction of intraluminal manometry/impedance measurement with five sensors at 4 cm intervals, and a sleeve sensor in the lower esophageal sphincter (LES). (B) Representation by overlaying manometry and impedance measurements with the videofluoroscopic appearance of a 5 mL swallowed barium bolus. The pressure scale for the thick, dark line is on the left, and the impedance scale for the light, thin line is on the right. The arrows point to the distribution of the bolus at the times indicated. As the bolus enters the esophagus, there is a slight increase in pressure at most sites, the “bolus pressure.” As the contraction reaches each site, the pressure increases and the impedance decreases. As the lumen closes and the upstroke of the pressure wave occurs, the tail of the barium bolus is evident. (C) Comparison of conventional manometric pressure tracing at five sites and the LES, as positioned in A, with the pressure profile obtained with high‐fidelity (high‐resolution) manometry and displayed topographically as an isocontour plot. The overlay places the two representations at similar locations. In the isocontour plot, deepening shades of gray indicate higher pressures. There are three pressure troughs: at the junction of the striated and smooth muscle esophagus; in the mid‐portion of the smooth muscle portion; and at the end of the peristaltic segment just before the LES. The troughs separate four different pressure segments, the last fronting the contraction closing the LES. The end of the LES relaxation measured with conventional manometry coincides with arrival of the contraction at the start of the fourth pressure segment and the LES.

Source: Pandolfino et al. [90] with permissions of Elsevier.