M. P. van Wijk

Development of pharyngo‐esophageal physiology during swallowing in the preterm infant

Background  Poor feeding is a common cause of prolonged hospitalization of preterm infants. Pharyngeal and upper esophageal sphincter (UES) function of preterm infants has been technically difficult to assess and is therefore poorly characterized. The aim of this study was to assess the development of pharyngeal motility, UES function, and their coordination during nutritive swallowing in preterm infants.

Esophageal impedance baselines in infants before and after placebo and proton pump inhibitor therapy

Background  Esophageal impedance monitoring records changes in conductivity. During esophageal rest, impedance baseline values may represent mucosal integrity. The aim of this study was to assess the influence of acid suppression on impedance baselines in a placebo‐controlled setting.

Applying the Chicago Classification criteria of esophageal motility to a pediatric cohort: effects of patient age and size

Applying the 2012 Chicago Classification (CC) of esophageal motility disorders to pediatric patients is problematic as it relies upon adult‐derived criteria. As shorter esophageal length and smaller esophago‐gastric junction (EGJ) diameter may influence CC metrics, we explored the potential for age‐ and size‐adjustment of diagnostic criteria.

Effect of lateral positioning on gastroesophageal reflux (GER) and underlying mechanisms in GER disease (GERD) patients and healthy controls.

Background  Posture has been shown to influence the number of transient lower esophageal sphincter relaxation (TLESRs) and gastroesophageal reflux (GER), however, the physiology explaining the influence of right lateral position (RLP), and left lateral position (LLP) is not clear. The aim of this study was to determine the influence of RLP and LLP on TLESRs and GERD after a meal in GER disease (GERD) patients and healthy controls (HC) while monitoring gastric distension and emptying.

Characterization of intraluminal impedance patterns associated with gas reflux in healthy volunteers

Abstract  Multichannel intraluminal impedance (MII) recording allows assessment of flow through the oesophagus and differentiation between liquid and gas contents. Existing MII criteria for recognition of gas gastro‐oesophageal reflux (GOR) have not been validated during known gas GOR in humans. Aims: (i) Characterize MII patterns of known gas GOR and optimize criteria. (ii) Clarify interrelationships between magnitude of maximal impedance change, luminal diameter and electrode‐mucosa contact. Ten healthy volunteers (six male, 21–37 years) were studied using an oesophageal MII‐manometry catheter. After catheter placement, subjects were asked to drink 600 mL of carbonated soft drink. Recordings were made for 20 min and the protocol repeated. Reported belches confirmed manometrically (triggered by transient lower oesophageal sphincter relaxations) were included for analysis. Those episodes were compared against commonly used criteria. Another five subjects (three male, 26–52 years) underwent simultaneous MII and videofluoroscopy using the same protocol. Videofluoroscopic images were analyzed for luminal diameter and the presence of electrode–mucosa contact. All analyzed gas GOR episodes (n = 88) were associated with a pattern of impedance rise which was either retrograde (62.5%), synchronous (19.3%) or antegrade (18.2%). Depending on the exact criteria used, sensitivity ranged from 33% to 75%. A multivariate regression model including luminal diameter and the presence of electrode‐mucosa contact as independent factors accounted for 53% of all variation in impedance changes. In conclusion, a significant number of gas GOR episodes does not meet criteria for their recognition. New criteria are proposed to include specific antegrade patterns of impedance rise. Luminal diameter and the extent of contact between the oesophageal mucosa and MII‐electrodes influence the magnitude and patterning of impedance change.

An expert panel-based study on recognition of gastro-esophageal reflux in difficult esophageal pH-impedance tracings.

Despite existing criteria for scoring gastro‐esophageal reflux (GER) in esophageal multichannel pH‐impedance measurement (pH‐I) tracings, inter‐ and intra‐rater variability is large and agreement with automated analysis is poor. To identify parameters of difficult to analyze pH‐I patterns and combine these into a statistical model that can identify GER episodes with an international consensus as gold standard.

Objectively diagnosing rumination syndrome in children using esophageal pH-impedance and manometry

Rumination syndrome is characterized by recurrent regurgitation of recently ingested food into the mouth. Differentiation with other diagnoses and gastroesophageal reflux disease (GERD) in particular, is difficult. Recently, objective pH‐impedance (pH‐MII) and manometry criteria were proposed for adults. The aim of this study was to determine diagnostic ambulatory pH‐MII and manometry criteria for rumination syndrome in children.

Intra- and interrater reliability of the Chicago Classification of achalasia subtypes in pediatric high-resolution esophageal manometry (HRM) recordings

Subtyping achalasia by high‐resolution manometry (HRM) is clinically relevant as response to therapy and prognosis have shown to vary accordingly. The aim of this study was to assess inter‐ and intrarater reliability of diagnosing achalasia and achalasia subtyping in children using the Chicago Classification (CC) V3.0.

Reflux monitoring in children

Recently, multichannel intraluminal impedance (MII) monitoring was added to the repertoire of tests to evaluate the (patho)physiology of gastroesophageal reflux (GER) in children. Its advantage above the sole monitoring of the esophageal pH lies in the ability of the detection of both acid and nonacid GER and to discern between liquid and gas GER. Currently, combined 24 h pH‐MII monitoring is recommended for evaluation of gastro‐esophageal reflux disease (GERD) and its relation to symptoms in infants and children, despite the lack of reference values in these age groups. There is new evidence in the current issue of this Journal supporting the role of pH‐MII monitoring for the evaluation of children presenting with gastrointestinal symptoms suggestive of GERD and the prediction of the presence of reflux esophagitis. However, several issues should be taken into account when performing pH‐MII clinically.

New Insights in Gastroesophageal Reflux, Esophageal Function and Gastric Emptying in Relation to Dysphagia Before and After Anti-Reflux Surgery in Children

In children with gastroesophageal reflux (GER) disease refractory to pharmacological therapies, anti-reflux surgery (fundoplication) may be a treatment of last resort. The applicability of fundoplication has been hampered by the inability to predict which patient may benefit from surgery and which patient is likely to develop post-operative dysphagia. pH impedance measurement and conventional manometry are unable to predict dysphagia, while the role of gastric emptying remains poorly understood. Recent data suggest that the selection of patients who will benefit from surgery might be enhanced by automated impedance manometry pressure-flow analysis (AIM) analysis, which relates bolus movement and pressure generation within the esophageal lumen.