Esophagogastric Junction Opening Research Articles

Restoration of Normal Distensive Characteristics of the Esophagogastric Junction After Fundoplication

To study the mechanical characteristics of the esophagogastric junction (EGJ) of postfundoplication patients and compare them with previously reported data on normal subjects and GERD patients. Eight normal subjects, 9 GERD patients, and 8 fundoplication patients were studied with concurrent manometry, fluoroscopy, and stepwise controlled barostat distention of the EGJ. The minimal barostat pressure required to open the EGJ during the interswallow period was determined. Thereafter, barium swallows were imaged in 5-mm Hg increments of intrabag pressure. EGJ diameter and length were measured at each pressure during deglutitive relaxation. EGJ opening diameter during deglutitive relaxation was on average 0.5 cm greater in GERD patients compared with normal subjects and fundoplication patients (P < 0.05). EGJ opening pressure and opening diameter were comparable between normal subjects and fundoplication patients; however, the EGJ length was 32% longer in fundoplication patients. Fundoplication restores distensibility of the EGJ to a level similar to normal subjects. Since trans-EGJ flow is related to EGJ length and EGJ diameter, these findings suggest that retrograde flow through the EGJ would be decreased by both a reduction in diameter and an increase in length of the EGJ.

A Novel Technique in Measuring Esophagogastric Junction (EGJ) Compliance with Catheter-Based Ultrasound: Dual Plane Reconstruction (DPR)

Background: Increased EGJ compliance can increase gastroesophageal reflux by creating wider EGJ opening dimensions during a reflux event or lowering the threshold for EGJ opening. The assessment of distensibility (defined as EGJ diameter vs. intraluminal pressure) of the EGJ using a barostat/fluoroscopy technique was previously described (Am J Physiol Gastrointest 2002). This technique required radiation exposure and only provided a single measurement of EGJ diameter and not cross-sectional area (CSA).

Measuring EGJ opening patterns using high resolution intraluminal impedance

The aim of this study was to adapt impedance methodology to study esophagogastric junction (EGJ) sphincter opening and compare opening patterns of the EGJ during deglutitive LES relaxation (dLESR) and transient LES relaxation (tLESR). We studied eight healthy subjects with a novel 12-lumen combined impedance/manometry catheter, the main element of which was a 6 cm sleeve sensor with six side hole sensors and six impedance rings spaced at 1 cm increments along its length. Subjects underwent an air infusion protocol after standard assessment and data tracings and isocontour plots were analysed to assess opening characteristics of the EGJ during dLESRs and tLESRs. Our results revealed that during dLESR the opening pattern was top to bottom, occurred in 0-2.7 s and in 29 of 35 (83%) cases the leading edge of the bolus was liquid. Opening during tLESR began between -7.8 and +8.6 s relative to the onset of nadir LES relaxation. The opening pattern during tLESR was bottom to top, occurred in 0-7.7 s, and in 22 of 29 (76%) the leading edge was liquid. These results support that impedance monitoring can be adapted to identify sphincter opening, to distinguish sphincter opening from sphincter relaxation, and to determine luminal contents during the opening period.

Esophagogastric junction opening during relaxation distinguishes nonhernia reflux patients, hernia patients, and normal subjects

Background & Aims : Flow across the esophagogastric junction (EGJ) is strongly related to opening dimensions. This study aimed to determine whether opening of the relaxed EGJ was altered in patients with gastroesophageal reflux disease (GERD). Methods : Seven normal subjects (NL), 9 GERD patients without hiatus hernia (NHH), and 7 with hiatus hernia (HH) were studied. Cross-sectional area (CSA) of the relaxed EGJ was measured during low-pressure distention using a modified barostat technique that resulted in filling a compliant bag straddling the EGJ with renograffin to the set pressure. Swallows were imaged fluoroscopically at distensive pressures of 2–12 mm Hg. The diameter of the narrowest point of the EGJ in PA and lateral projections was measured from digitized images. CSA was determined as a function of intrabag pressure. Results : The minimal EGJ opening aperture occurred at the diaphragmatic hiatus in all subjects. At pressures ≤0 mm Hg, EGJ opening was observed only in HH patients, making it plausible for these patients to reflux during deglutitive relaxation. At pressures >0 mm Hg, there were significant increases in EGJ CSA both for HH and NHH compared with NL ( P < 0.001) and for HH compared with NHH ( P < 0.005). This difference may explain the diminished air/water discrimination seen during transient lower esophageal sphincter (LES) relaxation-associated reflux in GERD patients. Conclusions : Anatomic degradation of the EGJ distinguishes GERD patients from normal subjects, and these changes may impact on both the observed mechanisms of reflux and the constituents of reflux during transient LES relaxation. Therapy focused on EGJ compliance may benefit GERD patients.

Esophagogastric junction opening: Does it explain the difference between normal subjects and patients with reflux disease?

Esophagogastric junction opening: Does it explain the difference between normal subjects and patients with reflux disease?

Esophagogastric junction distensibility: a factor contributing to sphincter incompetence

To quantify the effect of hiatus hernia (HH) on esophagogastric junction (EGJ) distensibility, eight normal subjects and nine gastroesophageal reflux disease (GERD) patients with HH were studied with concurrent manometry, fluoroscopy, and stepwise controlled barostatic distention of the EGJ. The minimal barostatic pressure required to open the EGJ during the interswallow period was determined. Thereafter, barium swallows were imaged in 5-mmHg increments of intrabag pressure. EGJ diameter and length were measured at each pressure during deglutitive relaxation. The EGJ opening diameter was greater in hernia patients compared with normal subjects during deglutitive relaxation at all pressures, and EGJ length was 23% shorter. EGJ opening pressure among hernia patients was lower than normal subjects during the interswallow period. In conclusion, the EGJ of GERD patients with HH was more distensible and shorter than normal subjects. These findings partially explain why HH patients are predisposed to reflux by mechanisms other than transient lower esophageal sphincter relaxations, sustain greater volumes of refluxate, and have a reduced ability to discriminate gas from liquid reflux.

Impact of fundoplication on bolus transit across esophagogastric junction.

This study analyzed the effect of fundoplication on the mechanics of liquid and solid bolus transit across the esophagogastric junction (EGJ). The squamocolumnar junction was endoscopically clipped in seven controls, seven hiatal hernia patients, and seven patients after laparoscopic Nissen fundoplication. Concurrent manometry and fluoroscopy were done during swallows of liquid barium and a 13-mm-diameter marshmallow. The EGJ opening, pressure gradients, transit efficacy, and axial motion were measured. The axial motion of the EGJ was reduced in the fundoplication and hiatal hernia patients. The opening dimensions at the squamocolumnar junction were similar among groups, but in each case the constriction limiting flow to the stomach was at the hiatus and this was substantially narrowed with fundoplication. As a result, liquid intrabolus pressure was increased and marshmallow transit frequently required multiple swallows. We conclude that fundoplication limits the axial mobility of the EGJ and leads to a restricted hiatal opening. These alterations decrease the efficacy of solid and liquid transit into the stomach and are potential causes of dysphagia in this population.