Deglutitive upper esophageal sphincter relaxation: a study of 75 volunteer subjects using solid-state high-resolution manometry

Abstract

. Deglutitive upper esophageal sphincter relaxation: a study of 75 volunteer subjects using solid-state high-resolution manometry. Am J Physiol Gastrointest Liver Physiol 291: G525-G531, 2006. First published April 27, 2006 doi:10.1152/ajpgi.00081.2006.-This study aimed to use a novel high-resolution manometry (HRM) system to establish normative values for deglutitive upper esophageal sphincter (UES) relaxation. Seventy-five asymptomatic controls were studied. A solid-state HRM assembly with 36 circumferential sensors spaced 1 cm apart was positioned to record from the hypopharynx to the stomach. Subjects performed ten 5-ml water swallows and one each of 1-, 10-, and 20-ml volume swallows. Pressure profiles across the UES were analyzed using customized computational algorithms that measured 1) the relaxation interval (RI), 2) the median intrabolus pressure (mIBP) during the RI, and 3) the deglutitive sphincter resistance (DSR) defined as mIBP/RI. The automated analysis succeeded in confirming bolus volume modulation of both the RI and the mIBP with the mean RI ranging from 0.32 to 0.50 s and mIBP ranging from 5.93 to 13.80 mmHg for 1-and 20-ml swallows, respectively. DSR was relatively independent of bolus volume. Peak pharyngeal contraction during the return to the resting state postswallow was almost 300 mmHg, again independent of bolus volume. We performed a detailed analysis of deglutitive UES relaxation with a novel HRM system and customized software. The enhanced spatial resolution of HRM allows for the accurate, automated assessment of UES relaxation and intrabolus pressure characteristics, in both cases confirming the volume-dependent effects and absolute values of these parameters previously demonstrated by detailed analysis of concurrent manometry/fluoroscopy data. Normative values were established to aid in future clinical and investigative studies. deglutitive sphincter resistance; relaxation interval; intrabolus pressure IT IS SOMEWHAT IRONIC that although the upper esophageal sphincter (UES) is the most accessible structure of the esophagus, it is in many ways the least well-understood. Several reflex pathways have been described linking the UES to the esophagus and pharynx (15,20,21,23,24) as have age-related changes in contractile vigor (2,7,22,25,31); however, with the exception of belch-related dysfunction (14, 15), none of these observations have yet been linked to pathological conditions. With respect to pathological conditions, the only clear dysfunction of the UES relates to alterations in its response during swallowing, specifically impaired UES opening during swallowing and impaired relaxation during swallow. Impaired opening, manifest as either stenosis with a cricopharyngeal bar or Zenker's diverticulum (5,8,26), is a recognized cause of dysphagia. Impaired relaxation is probably less common but can be related to neurological dysfunction, best characterized in the case of Parkinson's disease (1, 29). Thus, from a clinical perspective, the functional evaluation of the UES must, first an...

Modulation of Upper Esophageal Sphincter (UES) Relaxation and Opening During Volume Swallowing

“…Maximum axial UES pressure during the swallow was measured within the limits of UES area of interest over time. The location of maximum axial pressure was used to track the superior and inferior movement of the UES based on the method of Ghosh and colleagues [23]. Consecutive pressure and admittance values mapped to the corresponding position of the UES over time were used to derive an optimal profile of pressure and admittance during the swallow that could be correlated with CP-EMG and SM-EMG recordings.…”

Pressure-Flow Analysis for the Assessment of Pediatric Oropharyngeal Dysphagia

“…Additionally, we measured the UES nadir impedance (UESNI) as a marker of UES opening diameter (13), and the UES Resistance (UESRES) defined by UES intrabolus pressures over the relaxation period (14). The post-swallow impedance ratio (PSIR) is an integrated ratio that relates post-swallow impedance to the impedance during pharyngeal bolus passage.…”

“…The swallow risk index (SRI) is a separate composite score derived from four key swallow metrics previously found to differ in relation to aspiration risk (14). The SRI validation studies used simultaneous VFSS and HRIM with AIMplot analysis and showed a significantly higher SRI in patients with penetration-aspiration compared to patients without penetration or aspiration (13,14).…”

“…The SRI validation studies used simultaneous VFSS and HRIM with AIMplot analysis and showed a significantly higher SRI in patients with penetration-aspiration compared to patients without penetration or aspiration (13,14). Therefore, the SRI aims to quantify the overall level of swallowing dysfunction potentially predisposing to aspiration risk.…”

Effect of Bolus Volume and Viscosity on Pharyngeal Automated Impedance Manometry Variables Derived for Broad Dysphagia Patients

“…UES relaxation characteristics were measured using the established method of Ghosh et al, 2006 (11) which objectively calculated UES relaxation interval (UES RI), the UES nadir relaxation pressure (NadUESP), the median intrabolus pressure (UES IBP) and the UES resistance (calculated as UES IBP/UES RI).…”