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Microcombs, essential for various applications, benefit from tailored spectral shaping. Leveraging inverse design, we demonstrate versatile ”meta” dispersion control via multimode hybridization in photonic crystal ring resonators, offering promising avenues for advanced microcomb engineering.

We identify, via numerical simulations, the regime of enhanced frequency chirp during nonlinear propagation in multipass cell. This regime - used before the dawn of chirped pulse amplification to generate ultrashort pulses - paves the way for the generation of temporally clean few-cycle pulses. Here, we demonstrate numerically that the spectra of pulses from an Yb-based laser system can be broadened into a flat supercontinuum with a smooth spectral phase compatible with a clean few-cycle pulse with temporal secondary structures with peak intensity below 0.5% that of the main peak.

BACKGROUND: The racemic mixture, RS-(+/-)-alpha-lipoic acid (rac-LA) has been utilized clinically and in a variety of disease models. Rac-LA and the natural form, R-lipoic acid (RLA), are widely available as nutritional supplements, marketed as antioxidants. Rac-LA sodium salt (NaLA) or rac-LA potassium salt (KLA) has been used to improve the aqueous solubility of LA. STUDY RATIONALE: Several in vitro and animal models of aging and age-related diseases have demonstrated efficacy for the oral solutions of LA salts in normalizing age-related changes to those of young animals. Other models and studies have demonstrated the superiority of RLA, the naturally occurring isomer over rac-LA. Despite this, RLA pharmacokinetics (PK) is not fully characterized in humans, and it is unknown whether the concentrations utilized in animal models can be achieved in vivo. Due to its tendency to polymerize, RLA is relatively unstable and suffers poor aqueous solubility, leading to poor absorption and low bioavailability. A preliminary study demonstrated the stability and bioavailability were improved by converting RLA to its sodium salt (NaRLA) and pre-dissolving it in water. The current study extends earlier findings from this laboratory and presents PK data for the 600-mg oral dosing of 12 healthy adult subjects given NaRLA. In addition, the effect of three consecutive doses was tested on a single subject relative to a one-time dosing in the same subject to determine whether plasma maximum concentration (Cmax) and the area under the plasma concentration versus time curve (AUC) values were comparable to those in animal studies and those achievable via intravenous infusions in humans. METHODS: Plasma RLA was separated from protein by a modification of a published method. Standard curves were generated from spiking known concentrations of RLA dissolved in ethanol and diluted in a phosphate-buffered saline (PBS) into each individual's baseline plasma to account for inter-individual differences in protein binding and to prevent denaturing of plasma proteins. Plasma RLA content was determined by the percent recovery using high-performance liquid chromatography (electrochemical/coulometric detection) (HPLC/ECD). RESULTS: As anticipated from the preliminary study, NaRLA is less prone to polymerization, completely soluble in water, and displays significantly higher Cmax and AUC values and decreased time to maximum concentration (Tmax) and T1/2 values than RLA or rac-LA. In order to significantly extend Cmax and AUC, it is possible to administer three 600-mg RLA doses (as NaRLA) at 15-minute intervals to achieve plasma concentrations similar to those from a slow (20-minute) infusion of LA. This is the first study to report negligible unbound RLA even at the highest achievable plasma concentrations. [ABSTRACT FROM AUTHOR]

The Laboratory Accreditation Program (LAP) of the College of American Pathologists (CAP) is an ongoing activity to improve the quality of clinical laboratory services through voluntary participation, peer review, education, and compliance with established performance standards.From the outset, the LAP has been focused on improvement, and has always viewed its inspections as a consultative and collaborative relationship between the inspector and the laboratory. [ABSTRACT FROM AUTHOR]

Abstract Background Swine is an important agricultural commodity and biomedical model. Manipulation of the pig genome provides opportunity to improve production efficiency, enhance disease resistance, and add value to swine products. Genetic engineering can also expand the utility of pigs for modeling human disease, developing clinical treatment methodologies, or donating tissues for xenotransplantation. Realizing the full potential of pig genetic engineering requires translation of the complete repertoire of genetic tools currently employed in smaller model organisms to practical use in pigs. Results Application of transposon and recombinase technologies for manipulation of the swine genome requires characterization of their activity in pig cells. We tested four transposon systems- Sleeping Beauty, Tol2, piggyBac, and Passport in cultured porcine cells. Transposons increased the efficiency of DNA integration up to 28-fold above background and provided for precise delivery of 1 to 15 transgenes per cell. Both Cre and Flp recombinase were functional in pig cells as measured by their ability to remove a positive-negative selection cassette from 16 independent clones and over 20 independent genomic locations. We also demonstrated a Cre-dependent genetic switch capable of eliminating an intervening positive-negative selection cassette and activating GFP expression from episomal and genome-resident transposons. Conclusion We have demonstrated for the first time that transposons and recombinases are capable of mobilizing DNA into and out of the porcine genome in a precise and efficient manner. This study provides the basis for developing transposon and recombinase based tools for genetic engineering of the swine genome.

Background: Functional lumen imaging probe (FLIP) panometry assesses esophageal motility in response to controlled volumetric distension. This study aimed to describe the physiomechanical states of the lower esophageal sphincter (LES) in response to serial filling/emptying regimes for esophageal motility disorders., Methods: Fourty-five patients with absent contractile response on FLIP and diagnoses of normal motility (n = 6), ineffective esophageal motility (IEM; n = 8), scleroderma (SSc; n = 10), or nonspastic achalasia (n = 21) were included, as were 20 patient controls with normal motility on FLIP and manometry. LES diameter and pressure were measured after stepwise FLIP filling at 60 mL, 70 mL, and emptying to 60 mL with relative changes used to define physiomechanical states., Key Results: Passive dilatation after FLIP filling occurred in 63/65 (97%) patients among all diagnoses. After FLIP emptying, passive shortening occurred in 12/14 (86%) normal motility/IEM, 10/10 (100%) SSc, 9/21(43%) achalasia, and 16/20 (80%) controls, with auxotonic relaxation seen in 2/14 (14%) normal motility/IEM, 12/21 (57%) achalasia, and 4/20 (20%) controls. After achalasia treatment (LES myotomy), 21/21 (100%) achalasia had passive shortening after FLIP emptying., Conclusions & Inferences: Physiomechanical states of the LES can be determined via response to FLIP filling and emptying regimes. While passive shortening was the general response to FLIP emptying, auxotonic relaxation was observed in achalasia, which was disrupted by LES myotomy. Further investigation is warranted into the clinical impact on diagnosis and treatment of esophageal motility disorders., (© 2024 The Author(s). Neurogastroenterology & Motility published by John Wiley & Sons Ltd.)

Introduction: Four-dimensional high-resolution impedance manometry (4D HRM) uses impedance to estimate esophageal luminal cross-sectional area and track nadir impedance to measure intrabolus pressure (IBP). We aimed to determine whether 4D HRM metrics could define abnormal esophagogastric junction (EGJ) opening between Chicago Classification version 4.0 motility disorders and compare 4D HRM with functional lumen imaging probe (FLIP) metrics., Methods: Symptomatic adult patients who completed high-resolution impedance manometry and FLIP were included and compared with an asymptomatic control group. 4D HRM analysis used custom-built software to measure IBP, maximum EGJ diameter, and distensibility index on supine test swallows. 4D HRM metrics were compared with FLIP EGJ metrics., Results: Ninety patients (31 normal motility, 16 ineffective esophageal manometry, 9 absent contractility, 8 conclusive EGJ outflow obstruction [EGJOO], 12 type I achalasia, 14 type II achalasia, 12 type III achalasia, and 34 asymptomatic controls) were included. Phase 2 and 3 IBP was higher in type II and III achalasia compared with controls and normal motility groups ( P < 0.03). Maximum EGJ diameter and EGJ-distensibility index in the conclusive EGJOO and achalasia groups were significantly lower than in controls and normal motility groups ( P < 0.03). 4D HRM identified 37 of 44 (84%) subjects with normal EGJ opening and 29 of 39 (74%) subjects with reduced EGJ opening on FLIP., Discussion: 4D HRM metrics correlated with expected clinical observations across a spectrum of esophageal motility disorders and defined EGJ obstruction. 4D HRM metrics may have value in defining EGJ obstruction in equivocal cases related to EGJOO or absent peristalsis., (Copyright © 2024 by The American College of Gastroenterology.)

Introduction: We explored if a score derived from parameters from esophageal testing could increase confidence in diagnosing conclusive gastroesophageal reflux disease and in predicting outcome., Methods: A prediction score was developed using metrics based on Lyon Consensus 2.0 thresholds extracted from endoscopy and pH-impedance monitoring. The Lyon score was the sum of weighted scores derived from a logistic regression model. The outcome was response to antireflux therapy, defined as 50% reduction in global symptoms on validated questionnaires. An existing database of endoscopy-negative patients with typical reflux symptoms undergoing esophageal testing from 2 centers (Europe and the United States) constituted the developmental cohort, while 2 separate cohorts (Europe and Asia) served as validation cohorts. Receiver operating characteristics analysis determined performance of the Lyon score in predicting treatment response., Results: In 281 developmental cohort patients (median age 53 years, 57.7% female), the Lyon score demonstrated an area under the curve (AUC) of 0.819 in predicting 50% symptom improvement ( P < 0.001) on receiver operating characteristics, with an optimal threshold of 6.25 (sensitivity 81.2%, specificity 73.4%). Of the individual components, only acid exposure time (AUC 0.799, P < 0.001), mean nocturnal baseline impedance (AUC 0.785, P < 0.001), and reflux episodes (AUC 0.764, P < 0.001) approached the Lyon score performance. The Lyon score segregated treatment response in both the European (AUC 0.908, P < 0.001) and Asian validation cohorts (AUC 0.637, P < 0.001) and outperformed the DeMeester score in sensitivity for predicting outcome in the developmental and Asian validation cohorts., Discussion: The novel Lyon score segregates reflux phenotypes and identifies likelihood of symptom response from antireflux therapy., (Copyright © 2024 by The American College of Gastroenterology.)

Background and Aims: The diagnosis of achalasia is associated with an average delay of 2 years. Endoscopic features may prompt an earlier diagnosis. We aimed to develop and test a novel endoscopic score, CARS, for the prediction of achalasia., Methods: Part 1: Twenty endoscopic videos were taken from patients undergoing endoscopy for dysphagia or reflux. A survey with videos and endoscopic criteria options was distributed to 6 esophagologists and 6 general gastroenterologists. Inter-rater reliability (IRR) was measured and logistic regression was used to evaluate predictive performance. Three rounds of review were conducted to select the final score of 4 components. Part 2: A retrospective review was conducted for consecutive patients who had comprehensive esophageal testing. Each patient had a CARS endoscopic score calculated based on findings reported at endoscopy., Results: From a video review and analysis of score components, IRR ranged from 0.23 to 0.57 for score components. The final CARS score was selected based on the following 4 components: Contents, Anatomy, Resistance, and Stasis. In a mixed-effects model, the mean score across raters was higher for achalasia compared with nonachalasia subjects (4.44 vs 0.87; P < .01). In part 2 of the study, achalasia patients had a higher mean CARS score compared with those with no or ineffective motility disorder (mean 4.1 vs 1.3; P < .01)., Conclusions: We developed a CARS score based on reliability performance in a video-based survey and tested the score in a clinical setting. The CARS score performed well in predicting achalasia., Competing Interests: Disclosure The following authors disclosed financial relationships: D. A. Carlson: Consulting for Braintree and Medpace. R. F. Souza: consultant for Ironwood Pharmaceuticals, Castle Biosiences, Phathom Pharmaceuticals, IsoThrive, CDx, and AstraZeneca; research support from Phathom Pharmaceuticals and Sanofi. S. J. Spechler: Consultant for Takeda Pharmaceuticals, Interpace Diagnostics, Ironwood Pharmaceuticals, IsoThrive, Phathom Pharmaceuticals, and Castle Biosciences. J. F. Pandolfino: speaker, consultant, and advisory board member for Ethicon, Endogastric Solutions, Medtronic, and Diversatek; patent for FLIP panometry. V. J. A. Konda: honoraria from Medtronic; consultant for Castle Biosciences, Exact Sciences, Sebela, and Ambu. The other authors disclosed no financial relationships., (Copyright © 2024 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.)

There has been a sea of change in our understanding of the contribution of food to both our well-being and disease states. When one addresses "food as medicine," the concept of oxidative stress needs to be included. This review interconnects the basic science findings of oxidative stress and redox balance with the medicinal use of food, emphasizing optimization of the redox balance. To better illustrate the impacts of oxidative stress, the concept of the "triple oxidant sink" is introduced as a theoretical gauge of redox balance. Utilizing the concept, the true importance of dietary and lifestyle factors can be emphasized, including the limitations of supplements or a handful of "superfoods," if the remainder of the factors are pro-oxidant. The effects of a whole plant food diet compared with those of dietary supplements, processed foods, animal based nutrients, or additional lifestyle factors can be visually demonstrated with this concept. This paper provides an overview of the process, acknowledging that food is not the only mechanism for balancing the redox status, but one that can be strategically used to dramatically improve the oxidative state, and thus should be used as medicine., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Carlson, True and Wilson.)

Background: Esophageal motility disorders can be diagnosed by either high-resolution manometry (HRM) or the functional lumen imaging probe (FLIP) but there is no systematic approach to synergize the measurements of these modalities or to improve the diagnostic metrics that have been developed to analyze them. This work aimed to devise a formal approach to bridge the gap between diagnoses inferred from HRM and FLIP measurements using deep learning and mechanics., Methods: The "mechanical health" of the esophagus was analyzed in 740 subjects including a spectrum of motility disorder patients and normal subjects. The mechanical health was quantified through a set of parameters including wall stiffness, active relaxation, and contraction pattern. These parameters were used by a variational autoencoder to generate a parameter space called virtual disease landscape (VDL). Finally, probabilities were assigned to each point (subject) on the VDL through linear discriminant analysis (LDA), which in turn was used to compare with FLIP and HRM diagnoses., Results: Subjects clustered into different regions of the VDL with their location relative to each other (and normal) defined by the type and severity of dysfunction. The two major categories that separated best on the VDL were subjects with normal esophagogastric junction (EGJ) opening and those with EGJ obstruction. Both HRM and FLIP diagnoses correlated well within these two groups., Conclusion: Mechanics-based parameters effectively estimated esophageal health using FLIP measurements to position subjects in a 3-D VDL that segregated subjects in good alignment with motility diagnoses gleaned from HRM and FLIP studies., (© 2024 The Author(s). Neurogastroenterology & Motility published by John Wiley & Sons Ltd.)

Esophagogastroduodenoscopy (EGD) is recommended in patients with typical gastroesophageal reflux disease (GERD) symptoms (heartburn, regurgitation, chest pain) in the setting of proton pump inhibitor (PPI) nonresponse. EGD evaluates for erosive disease, assesses antireflux barrier integrity, excludes non-GERD conditions, and, in the absence of erosive findings, is followed by reflux testing. 1,2 The diagnostic utility of EGD is less clear in the evaluation for laryngopharyngeal reflux (LPR), and the current reference standard is ambulatory reflux monitoring. 1,3,4 This study of patients referred for evaluation of chronic laryngeal symptoms had the following aims: (1) to characterize endoscopic findings, (2) to discern whether findings differed between patients with or without concomitant esophageal reflux symptoms, and (3) to measure the association between endoscopic findings and objective GERD on ambulatory reflux monitoring., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background/aims: Cholecystokinin (CCK) administration has been shown to reduce lower esophageal sphincter (LES) pressure in normal subjects in manometric studies. Functional luminal imaging probe (FLIP) panometry offers a method to assess esophageal motility in response to sustained distension though mechanisms related to this response remain unexplored. The aim of this study is to evaluate the effect of CCK-8 on the esophageal response to distension in asymptomatic volunteers using FLIP., Methods: Esophageal response to distension was studied in 7 asymptomatic volunteers (mean age ± SD [27 ± 2]; 86% female) before and after CCK-8 administration in a crossover study design. During sedated endoscopy, FLIP was performed twice with CCK-8 administered via intravenous push in one of 2 protocols: during filling (n = 4) or during emptying (n = 3). Esophagogastric junction distensibility index (EGJ-DI) at 60 mL fill volume and esophageal body contractile response patterns were analyzed., Results: During the baseline FLIP study, all subjects had a contractile response with repetitive antegrade contractions both before and after CCK-8 administration. However, a sustained LES contraction or a sustained occluding contraction with esophageal shortening was observed in all subjects in the filling protocol, but in none during the emptying protocol. EGJ-DI was similar before and after CCK-8 during both filling (4.7 ± 1.9 mm 2 /mmHg vs 4.3 ± 1.8 mm 2 /mmHg) and emptying protocol (7.5 ± 1.4 mm 2 /mmHg vs 6.9 ± 0.6 mm 2 /mmHg)., Conclusion: While EGJ-DI appeared unaffected by CCK-8 administration in asymptomatic volunteers, CCK induced spastic-reactive contractions of the LES during distention suggesting that exogenous CCK interferes with normal LES relaxation during secondary peristalsis.

Background: Eosinophilic esophagitis (EoE) is a chronic T helper type 2 (Th2)-associated inflammatory disorder triggered by food allergens, resulting in esophageal dysfunction through edema, fibrosis, and tissue remodeling. The role of epithelial remodeling in EoE pathogenesis is critical but not fully understood., Objective: To investigate the role of epithelial IKKβ/NFκB signaling in EoE pathogenesis using a mouse model with conditional Ikk β knockout in esophageal epithelial cells ( Ikk β EEC-KO )., Methods: EoE was induced in Ikkβ EEC-KO mice through skin sensitization with MC903/Ovalbumin (OVA) followed by intraesophageal OVA challenge. Histological and transcriptional analyses were performed to assess EoE features. Single-cell RNA sequencing (scRNA-seq) was used to profile esophageal mucosal cell populations and gene expression changes., Results: Ikkβ EEC-KO /EoE mice exhibited hallmark EoE features, including eosinophil infiltration, intraepithelial eosinophils, microabscesses, basal cell hyperplasia, and lamina propria remodeling. RNA-seq revealed significant alterations in IKKβ/NFκB signaling pathways, with decreased expression of RELA and increased expression of IKKβ negative regulators. scRNA- seq analyses identified disrupted epithelial differentiation and barrier integrity, alongside increased type 2 immune responses and peptidase activity., Conclusion: Our study demonstrates that loss of epithelial IKKβ signaling exacerbates EoE pathogenesis, highlighting the critical role of this pathway in maintaining epithelial homeostasis and preventing allergic inflammation. The Ikkβ EEC-KO /EoE mouse model closely mirrors human EoE, providing a valuable tool for investigating disease mechanisms and therapeutic targets. This model can facilitate the development of strategies to prevent chronic inflammation and tissue remodeling in EoE., Key Messages: Critical Role of Epithelial IKKβ/NFκB Signaling: Loss of this signaling exacerbates EoE, causing eosinophil infiltration, basal cell hyperplasia, and tissue remodeling, highlighting its importance in esophageal health.Molecular Insights and Therapeutic Targets: scRNA-seq identified disrupted epithelial differentiation, barrier integrity, and enhanced type 2 immune responses, suggesting potential therapeutic targets for EoE. Relevance of the Ikkβ EEC-KO /EoE Mouse Model: This model replicates human EoE features, making it a valuable tool for studying EoE mechanisms and testing treatments, which can drive the development of effective therapies., Capsule Summary: This study reveals the crucial role of epithelial IKKβ/NFκB signaling in EoE, providing insights into disease mechanisms and potential therapeutic targets, highly relevant for advancing clinical management of EoE.

Background: The objective measurement for esophageal bolus volume and bolus clearance could classify abnormal high-resolution manometry (HRM) beyond the current Chicago classification. We aimed to compare the novel four-dimensional impedance manometry (4D HRM) volume metrics with timed barium esophagram (TBE)., Methods: Adults with esophageal symptoms undergoing HRM and TBE were included. A custom-built program for 4D HRM analysis measured esophageal luminal cross-sectional area (CSA) from impedance and subsequently derived esophageal bolus volume and clearance. 4D HRM volume metrics included pre-swallow residual volume, maximal volume, retention volume, and clearance ratio defined as 1.0-retention volume divided by the maximal volume. An abnormal TBE was defined as a column height >5 cm at 1 min or 5 min., Key Results: A total of 95 patients (normal motility: 33%; ineffective esophageal motility: 12%; absent contractility: 10%; esophagogastric junction outflow obstruction: 30%; type I achalasia: 5%; type II achalasia: 12%) were categorized into normal TBE (58%), abnormal TBE at 1 min (17%), and abnormal TBE at 5 min (25%). The AUROC demonstrated that, among all 4D HRM volume metrics, the clearance ratio had the best performance in predicting abnormal TBE at 5 min (AUROC, 95% confidence interval: 0.89, 0.82-0.96), and exhibited a strong negative correlation with TBE at 5 min (r = -0.65; p < 0.001)., Conclusions & Inferences: Novel 4D HRM volume metrics provide objective measurement of esophageal bolus volume and bolus clearance. The clearance ratio has a strong correlation with TBE and could potentially serve as a substitute for TBE to measure esophageal retention., (© 2024 The Authors. Neurogastroenterology & Motility published by John Wiley & Sons Ltd.)

Background: Functional lumen imaging probe (FLIP) panometry evaluates esophageal motility, including the contractile response to distension, that is, secondary peristalsis. Impaired/disordered contractile response (IDCR) is an abnormal, but nonspecific contractile response that can represent either hypomotility or spastic motor disorders on high-resolution manometry (HRM). We hypothesized that FLIP pressure could be incorporated to clarify IDCR and aimed to determine its utility in a cohort of symptomatic esophageal motility patients., Methods: 173 adult patients that had IDCR on FLIP panometry and HRM with a conclusive Chicago Classification v4.0 (CCv4.0) diagnosis were included and analyzed as development (n = 118) and validation (n = 55) cohorts. FLIP pressure values were assessed for prediction of either hypomotility or spasm, defined on HRM/CCv4.0., Key Results: HRM/CCv4.0 diagnoses were normal motility in 48 patients (28%), "hypomotility" (ineffective esophageal motility, absent contractility, or Type I or II achalasia) in 89 (51%), and "spasm" (Type III achalasia, distal esophageal spasm, or hypercontractile esophagus) in 36 (21%). The pressure at esophagogastric junction-distensibility index (DI) (60 mL) was lower in hypomotility (median [interquartile range] 34 [28-42] mmHg) than in spasm (49 [40-62] mmHg; p < 0.001) and had an area under the receiver operating characteristic curve of 0.80 (95% CI 0.73-0.88) for hypomotility and 0.76 (0.69-0.83) for spasm. For "spasm" on HRM, a threshold FLIP pressure of >35 mmHg provided 90% sensitivity (47% specificity) while >55 mmHg provided 93% specificity (40% sensitivity)., Conclusion & Inferences: Pressure on FLIP panometry can help clarify the significance of IDCR, with low-pressure IDCR associated with hypomotility and high-pressure IDCR suggestive of spastic motor disorders., (© 2024 The Authors. Neurogastroenterology & Motility published by John Wiley & Sons Ltd.)

Age-related changes in esophageal function involve increased rates of dysmotility with advancing age (sometimes described as presbyesophagus). 1-4 Specifically, advanced age has been associated with increased lower esophageal sphincter (LES) pressure and decreased peristaltic vigor. 1-4 However, the mechanisms underlying these changes, including the relative relationship of primary peristalsis and secondary peristalsis over the lifespan, remain incompletely understood. Current approaches assess primary peristalsis using high-resolution manometry (HRM), with esophageal motility disorders defined using the Chicago Classification version 4.0 (CCv4.0), and secondary peristalsis using functional lumen imaging probe (FLIP) panometry. 5,6 Although HRM and FLIP panometry motility diagnoses are often analogous, they can sometimes differ. For example, abnormal secondary peristalsis can occur when primary peristalsis is normal, which has been associated with reflux and non-obstructive dysphagia. 7,8 This study aimed to examine the effect of age on primary peristalsis and secondary peristalsis., (Copyright © 2024 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Background: Despite the established efficacy of achalasia treatments on symptomatic outcomes, there are limited data evaluating the treatment effect on esophageal dilatation. This study aimed to assess the effect achalasia treatment on esophageal dilatation and the effect of esophageal width reduction ("recoil") on clinical outcomes., Methods: Patients with type I or type II achalasia that completed high-resolution manometry (HRM), functional lumen imaging probe (FLIP), and timed barium esophagram (TBE) pre and post treatment were included. Esophageal width was measured using TBE. Focused subgroup analysis was performed on patients with normal posttreatment EGJ opening on FLIP. Good clinical outcomes were defined as barium column height of <5 cm at 5 min and Eckardt Score ≤3., Key Results: Sixty-nine patients (41% type I and 59% type II) were included. Esophageal width decreased from pre to post treatment mean (SD) 4.2 (1.3) cm-2.8 (1.2) cm; p < 0.01. In the normal post treatment EGJ opening subgroup, esophageal width was less in patients with good TBE outcome compared to poor outcome mean (SD) 2.2 (0.7) cm versus 3.2 (1.4) cm (p < 0.01), but did not differ in good versus poor symptomatic outcome groups. Esophageal width recoil >25% posttreatment was associated with a greater rate of good TBE outcome (71% vs. 50%, p = 0.04) and good symptomatic outcome (88% vs. 50%; p = 0.04)., Conclusions and Inferences: Esophageal recoil was associated with good achalasia treatment outcome in patients without posttreatment EGJ obstruction. This suggests that mechanical properties of the esophageal wall, likely associated with tissue remodeling, play a role in clinical outcomes following achalasia treatment., (© 2024 The Authors. Neurogastroenterology & Motility published by John Wiley & Sons Ltd.)

Background & Aims: Discerning whether laryngeal symptoms result from gastroesophageal reflux is clinically challenging and a reliable tool to stratify patients is needed. We aimed to develop and validate a model to predict the likelihood of gastroesophageal reflux disease (GERD) among patients with chronic laryngeal symptoms., Methods: This multicenter international study collected data from adults with chronic laryngeal symptoms who underwent objective testing (upper gastrointestinal endoscopy and/or ambulatory reflux monitoring) between March 2018 and May 2023. The training phase identified a model with optimal receiver operating characteristic curves, and β coefficients informed a weighted model. The validation phase assessed performance characteristics of the weighted model., Results: A total of 856 adults, 304 in the training cohort and 552 in the validation cohort, were included. In the training phase, the optimal predictive model (area under the curve, 0.68; 95% CI, 0.62-0.74), was the Cough, Overweight/obesity, Globus, Hiatal Hernia, Regurgitation, and male seX (COuGH RefluX) score, with a lower threshold of 2.5 and an upper threshold of 5.0 to predict proven GERD. In the validation phase, the COuGH RefluX score had an area under the curve of 0.67 (95% CI, 0.62-0.71), with 79% sensitivity and 81% specificity for proven GERD., Conclusions: The externally validated COuGH RefluX score is a clinically practical model to predict the likelihood of proven GERD. The score classifies most patients with chronic laryngeal symptoms as low/high likelihood of proven GERD, with only 38% remaining as indeterminate. Thus, the COuGH RefluX score can guide diagnostic strategies and reduce inappropriate proton pump inhibitor use or testing for patients referred for evaluation of chronic laryngeal symptoms., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: The impact of esophageal dysmotility among patients with post-fundoplication esophageal symptoms is not fully understood. This study aimed to investigate secondary peristalsis and esophagogastric junction (EGJ) opening biomechanics using functional lumen imaging probe (FLIP) panometry in symptomatic post-fundoplication patients., Methods: Eighty-seven adult patients post-fundoplication who completed FLIP for symptomatic esophageal evaluation were included. Secondary peristaltic contractile response (CR) patterns and EGJ opening metrics (EGJ distensibility index (EGJ-DI) and maximum EGJ diameter) were evaluated on FLIP panometry and analyzed against high-resolution manometry (HRM), patient-reported outcomes, and fundoplication condition seen on esophagram and/or endoscopy., Key Results: FLIP CR patterns included 14 (16%) normal CR, 30 (34%) borderline CR, 28 (32%) impaired/disordered CR, 13 (15%) absent CR, and 2 (2%) spastic reactive CR. Compared with normal and borderline CRs (i.e., CR patterns with distinct, antegrade peristalsis), patients with impaired/disordered and absent CRs demonstrated significantly greater time since fundoplication (2.4 (0.6-6.8) vs. 8.9 (2.6-14.5) years; p = 0.002), greater esophageal body width on esophagram (n = 50; 2.3 (2.0-2.8) vs. 2.9 (2.4-3.6) cm; p = 0.013), and lower EGJ-DI (4.3 (2.7-5.4) vs. 2.6 (1.7-3.7) mm 2 /mmHg; p = 0.001). Intact fundoplications had significantly higher rates of normal CRs compared to anatomically abnormal (i.e., tight, disrupted, slipped, herniated) fundoplications (9 (28%) vs. 5 (9%); p = 0.032), but there were no differences in EGJ-DI or EGJ maximum diameter., Conclusions & Inferences: Symptomatic post-fundoplication patients were characterized by frequent abnormal secondary peristalsis after fundoplication, potentially worsening with time after fundoplication or related to EGJ outflow resistance., (© 2024 The Authors. Neurogastroenterology & Motility published by John Wiley & Sons Ltd.)

Background and Aims: The evaluation provided by functional lumen imaging probe (FLIP) panometry includes esophageal distensibility/compliance (mechanics) of the esophageal body and esophagogastric junction (EGJ) and esophageal motility (secondary peristalsis). We developed a composite score using these parameters to characterize physiomechanical function in patients with eosinophilic esophagitis (EoE)., Methods: Two hundred fifteen adult patients with EoE who completed FLIP panometry during sedated endoscopy with esophageal biopsy sampling were included. FLIP metrics of esophageal body Compliance, Contractile response, Distensibility plateau, and maximum EGJ Diameter (C2D2) were scored as 0 for normal versus 1 or 2 for increasing degree of abnormality. Scores were summed to calculate the composite C2D2 score., Results: The C2D2 score had a significant positive correlation with mucosal eosinophil count (ρ = .241) and total Endoscopic EoE Reference Score (ρ = .467). Among 46 patients off treatment at the baseline evaluation, future proton pump inhibitor (PPI) responders (ie, achieved mucosal eosinophil count <15 per high-powered field after PPI treatment) had lower C2D2 scores than PPI nonresponders (median, 2 [interquartile range, 1-3] vs 4 [interquartile range, 2-6], respectively; P = .003). A regression model (that controlled for age, sex, and baseline eosinophil count) showed a C2D2 score ≤3 had an odds ratio of 14.5 (95% confidence interval, 2.6-85) to predict future PPI response. However, total Endoscopic EoE Reference Scores (P = .142) and baseline eosinophil count (P = .480) did not differ between PPI responders and PPI nonresponders., Conclusions: This composite score of FLIP panometry metrics, the C2D2 score, may facilitate characterizing physiomechanical function in EoE and serve as an objective outcome measure., Competing Interests: Disclosure The following authors disclosed financial relationships: D. A. Carlson: Consultant for Medtronic, Phathom Pharmaceuticals, Braintree, and Medpace; speaker for Medtronic; licensing agreement with Medtronic. I. Hirano: Consultant for Adare/Ellodi, Allakos, AstraZeneca, Celgene/Receptos/Bristol Meyers Squibb, Sanofi/Regeneron, Shire/Takeda, Amgen, Arena, Eli Lilly, EsoCap, Gossamer Bio, and Parexel/Calyx; research support from Adare/Ellodi, Allakos, AstraZeneca, Celgene/Receptos/Bristol Meyers Squibb, Sanofi/Regeneron, Shire/Takeda, and Arena; speaker for Sanofi/Regeneron and Shire/Takeda. N. Gonsalves: Consultant for Allakos, AstraZeneca, Abbvie, Sanofi-Regeneron, Nutricia, Knopp Pharma, and BMS; speaker for Takeda and Sanofi-Regeneron. P. J. Kahrilas: Consultant for Reckitt and Ironwood; licensing agreement with Medtronic. J. E. Pandolfino: Consultant for Sandhill Scientific/Diversatek, Medtronic, Torax/Ethicon, EndoGastric Solutions, Ironwood, and Phathom Pharmaceuticals; speaker for Sandhill Scientific/Diversatek, Takeda, AstraZeneca, Medtronic, Torax/Ethicon, and EndoGastric Solutions; research support from Sandhill Scientific/Diversatek; licensing agreement with Medtronic. All other authors disclosed no financial relationships., (Copyright © 2024 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.)

Introduction: Among patients with chronic laryngeal symptoms, ambulatory reflux monitoring off acid suppression is recommended to evaluate for laryngopharyngeal reflux (LPR). However, reflux monitoring systems are diverse in configuration and monitoring capabilities, which present a challenge in creating a diagnostic reference standard in these patients. This study aimed to compare diagnostic yield and performance between reflux monitoring systems in patients with chronic laryngeal symptoms., Methods: This multicenter, international study of adult patients referred for evaluation of LPR over a 5-year period (March 2018-May 2023) assessed and compared diagnostic yield of pathologic gastroesophageal reflux (GER+) on ambulatory reflux monitoring off acid suppression., Results: Of 813 patients, 296 (36%) underwent prolonged wireless pH, 532 (65%) underwent 24-hour pH-impedance monitoring, and 15 (2%) underwent both tests. Overall diagnostic yield for GER+ was 36% and greater for prolonged wireless pH compared with that for 24-hour pH-impedance monitoring (50% vs 27%; P < 0.01). Among 15 patients who underwent both prolonged wireless pH and 24-h pH-impedance monitoring, concordance between systems for GER+ was 40%. The most common source of discordance was strong evidence of GER+ across multiple days on prolonged wireless pH compared with no evidence of GER+ on pH-impedance., Discussion: In this multicenter international study of patients with chronic laryngeal symptoms referred for LPR evaluation, diagnostic yield of ambulatory reflux monitoring off acid suppression was 36% and rose to 50% when using wireless pH monitoring. In patients referred for chronic laryngeal symptoms, 24-hour pH-impedance monitoring may risk a low negative predictive value in patients with unproven GER+ disease., (Copyright © 2023 by The American College of Gastroenterology.)

Background and Aims: Some achalasia patients exhibit esophageal contractile activity on follow-up after treatment, yet its importance remains unclear. We aimed to identify factors associated with presence of contractility after treatment and to assess its impact on timed barium esophagram (TBE) and clinical outcomes., Methods: Patients with type I or II achalasia on baseline high-resolution manometry (HRM) who completed HRM, TBE, and functional lumen imaging probe (FLIP) after treatment were retrospectively identified. Contractility was defined on post-treatment HRM as presence of at least 1 supine swallow with DCI ≥100 mmHg s cm., Key Results: One hundred twenty-two patients were included (mean age 48 ± 17 years, 50% female). At follow-up evaluation after treatment (54% peroral endoscopic myotomy, 24% pneumatic dilation, 22% laparoscopic Heller myotomy), 61 (50%) patients had contractility on HRM. Patients with contractility (compared to those without) more frequently had type II achalasia (84% vs 57%, p = 0.001) and a post-treatment normal EGJ opening classification on FLIP (69% vs 49%; p < 0.001). In the subgroup of patients with post-treatment integrated relaxation pressure <15 mmHg and normal EGJ opening on FLIP (n = 53), those with contractility had a lower median column height on TBE at 1 min (4 vs 7 cm, p = 0.002) and 5 min (0 vs 5 cm, p = 0.001). In patients with "abnormal" EGJ metrics, patients with contractility showed lower symptom scores (median Eckardt score 2 vs 3, p = 0.03)., Conclusions & Inferences: Occurring more frequently in type II achalasia, and if adequate EGJ opening is achieved after treatment, esophageal contractility may contribute to improved esophageal emptying and improved symptoms in non-spastic achalasia. Preservation of esophageal body muscle could improve outcomes in these patients., (© 2023 The Authors. Neurogastroenterology & Motility published by John Wiley & Sons Ltd.)

Background & Aims: Chronic inflammation of eosinophilic esophagitis (EoE) results in progressive, fibrostenotic remodeling of the esophageal wall. This study aimed to demonstrate objective changes in esophageal distensibility relative to duration of EoE disease using a functional lumen imaging probe (FLIP)., Methods: Adult patients with EoE who completed a 16-cm FLIP protocol during endoscopy were evaluated in a cross-sectional study. FLIP analysis focused on distensibility plateau (DP) of the esophageal body. The time from onset of symptoms to time of endoscopy with FLIP was assessed, as was time from symptom onset to EoE diagnosis (ie, diagnostic delay)., Results: A total of 171 patients (mean age 38 ± 12 years; 31% female) were included; the median symptom duration was 8 (interquartile range, 3-15) years and diagnostic delay was 4 (interquartile range, 1-12) years. At the time of endoscopy with FLIP, there were 54 patients (39%) in histologic remission (<15 eosinophils per high-power field [eos/hpf]). Symptom duration and diagnostic delay were negatively correlated with DP (rho = -0.326 and -0.309; P values < .001). Abnormal esophageal distensibility (DP ≤17 mm) was more prevalent with increased duration of symptoms (P < .004): 23% at <5 years to 64% at ≥25 years. When stratifying the cohort based on mucosal eosinophil density, patients with ≥15 eos/hpf had significantly lower DP with greater symptom duration (P = .004), while there was not a significant difference among patients with <15 eos/hpf (P = .060)., Conclusions: Esophageal distensibility objectively measured with FLIP was reduced in EoE patients with greater symptom duration and diagnostic delay. This supports that EoE is a progressive, fibrostenotic disease and that FLIP may be a useful tool to monitor disease progression in EoE., (Copyright © 2024 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Functional luminal imaging probe (FLIP) is used to measure cross-sectional area (CSA) and pressure at sphincters. It consists of a catheter surrounded by a fluid filled cylindrical bag, closed on both ends. Plotting the pressure-CSA hysteresis of a sphincter during a contraction cycle, which is available through FLIP testing, offers information on its functionality, and can provide diagnostic insights. However, limited work has been done to explain the mechanics of these pressure-CSA loops. This work presents a consolidated picture of pressure-CSA loops of different sphincters. Clinical data reveal that although sphincters have a similar purpose (controlling the flow of liquids and solids by opening and closing), two different pressure-CSA loop patterns emerge: negative slope loop (NSL) and positive slope loop (PSL). We show that the loop type is the result of an interplay between (or lack thereof) two mechanical modes: (i) neurogenic mediated relaxation of the sphincter muscle or pulling applied by external forces, and (ii) muscle contraction proximal to the sphincter which causes mechanical distention. We conclude that sphincters which only function through mechanism (i) exhibition NSL whereas sphincters which open as a result of both (i) and (ii) display a PSL. This work provides a fundamental mechanical understanding of human sphincters. This can be used to identify normal and abnormal phenotypes for the different sphincters and help in creating physiomarkers based on work calculation., (Copyright © 2024 by ASME.)

Background and Aims: The distal contractile integral (DCI) quantifies the contractile vigor of primary peristalsis on high-resolution manometry (HRM), whereas no such metric exists for secondary peristalsis on functional lumen imaging probe (FLIP) panometry. This study aimed to evaluate novel FLIP metrics of contraction power and displaced volume in asymptomatic controls and a patient cohort., Methods: Thirty-five asymptomatic controls and adult patients (with normal esophagogastric junction outflow/opening and without spasm) who completed HRM and FLIP panometry were included. The patient group also completed timed barium esophagram (TBE). Contraction power (estimate of esophageal work over time) and displaced volume (estimate of contraction-associated fluid flow) were computed from FLIP. HRM was analyzed per Chicago Classification v4.0., Key Results: In controls, median (5th-95th percentile) contraction power was 27 mW (10-44) and displaced volume was 43 mL (17-66). 95 patients were included: 72% with normal motility on HRM, 17% with ineffective esophageal motility (IEM), and 12% with absent contractility. Among patients, DCI was significantly correlated with both contraction power (rho = 0.499) and displaced volume (rho = 0.342); p values < 0.001. Both contraction power and displaced volume were greater in patients with normal motility versus IEM or absent contractility, complete versus incomplete bolus transit, and normal versus abnormal retention on TBE; p values < 0.02., Conclusions: FLIP panometry metrics of contraction power and displaced volume appeared to effectively quantify peristaltic vigor. These novel metrics may enhance evaluation of esophageal motility with FLIP panometry and provide a reliable surrogate to DCI on HRM., (© 2023 The Authors. Neurogastroenterology & Motility published by John Wiley & Sons Ltd.)

Background: The esophageal response to stepwise distension during the functional lumen imaging probe (FLIP) Panometry study often parallels high-resolution manometry (HRM) motility diagnoses. This study aimed to describe the changes in FLIP metrics during FLIP emptying, that is, reduced volume distension., Methods: Adult patients who completed FLIP and HRM for esophageal motility evaluation were included. Esophagogastric junction (EGJ) opening parameters were assessed during stepwise FLIP filling to volumes of 60 mL ("filling 60 mL"), then 70 mL, and then back to 60 mL ("emptying 60 mL"). HRM studies were analyzed per Chicago classification version 4.0 (CCv4.0)., Key Results: Among 265 patients included, HRM/CCv4.0 diagnoses included achalasia in 80 patients (30%), normal motility in 70 (26%), and ineffective esophageal motility (IEM) in 43 (16%). EGJ-distensibility index (DI) and EGJ diameter were greater during emptying 60 mL than filling 60 mL in achalasia, normal motility, and IEM (p values <0.002). If applying the emptying 60 mL EGJ-DI (vs. filling 60 mL EGJ-DI), EGJ opening classification changed from reduced EGJ opening to borderline EGJ opening in 31% of achalasia patients and in 2% of patients with normal motility or IEM. EGJ opening classification was unchanged in 69% achalasia and 96% of normal motility/IEM., Conclusions and Inferences: This study suggests that isotonic or auxotonic relaxation of the lower esophageal sphincter occurs with reduced volume distension in patients with achalasia and normal motility. The study also supports the importance of utilizing a standardized FLIP motility study protocol (i.e., controlled, stepwise filling to 50 mL, 60 mL, then 70 mL) to provide reliable and generalizable FLIP metrics to facilitate diagnosis of esophageal motility disorders., (© 2023 The Authors. Neurogastroenterology & Motility published by John Wiley & Sons Ltd.)

Eosinophilic esophagitis (EoE) is an esophageal immune-mediated disease characterized by eosinophilic inflammation and epithelial remodeling, including basal cell hyperplasia (BCH). Although BCH is known to correlate with disease severity and with persistent symptoms in patients in histological remission, the molecular processes driving BCH remain poorly defined. Here, we demonstrate that BCH is predominantly characterized by an expansion of nonproliferative suprabasal cells that are still committed to early differentiation. Furthermore, we discovered that suprabasal and superficial esophageal epithelial cells retain progenitor identity programs in EoE, evidenced by increased quiescent cell identity scoring and the enrichment of signaling pathways regulating stem cell pluripotency. Enrichment and trajectory analyses identified SOX2 and KLF5 as potential drivers of the increased quiescent identity and epithelial remodeling observed in EoE. Notably, these alterations were not observed in gastroesophageal reflux disease. These findings provide additional insights into the differentiation process in EoE and highlight the distinct characteristics of suprabasal and superficial esophageal epithelial cells in the disease.

Background: Primary and secondary peristalsis facilitate esophageal bolus transport; however, their relative impact for bolus clearance remains unclear. We aimed to compare primary peristalsis and contractile reserve on high-resolution manometry (HRM) and secondary peristalsis on functional lumen imaging probe (FLIP) Panometry with emptying on timed barium esophagogram (TBE) and incorporate findings into a comprehensive model of esophageal function., Methods: Adult patients who completed HRM with multiple rapid swallows (MRS), FLIP, and TBE for esophageal motility evaluation and without abnormal esophagogastric junction outflow/opening or spasm were included. An abnormal TBE was defined as a 1-min column height >5 cm. Primary peristalsis and contractile reserve after MRS were combined into an HRM-MRS model. Secondary peristalsis was combined with primary peristalsis assessment to describe a complementary neuromyogenic model., Key Results: Of 89 included patients, differences in rates of abnormal TBEs were observed with primary peristalsis classification (normal: 14.3%; ineffective esophageal motility: 20.0%; absent peristalsis: 54.5%; p = 0.009), contractile reserve (present: 12.5%; absent: 29.3%; p = 0.05), and secondary peristalsis (normal: 9.7%; borderline: 17.6%; impaired/disordered: 28.6%; absent contractile response: 50%; p = 0.039). Logistic regression analysis (akaike information criteria, area under the receiver operating curve) demonstrated that the neuromyogenic model (80.8, 0.83) had a stronger relationship predicting abnormal TBE compared to primary peristalsis (81.5, 0.82), contractile reserve (86.8, 0.75), or secondary peristalsis (89.0, 0.78)., Conclusions and Inferences: Primary peristalsis, contractile reserve, and secondary peristalsis were associated with abnormal esophageal retention as measured by TBE. Added benefit was observed when applying comprehensive models to incorporate primary and secondary peristalsis supporting their complementary application., (© 2023 The Authors. Neurogastroenterology & Motility published by John Wiley & Sons Ltd.)

Background & Aims: Eosinophilic esophagitis (EoE) is characterized by eosinophilic inflammation, but also heterogeneous presentations involving fibrostenotic esophageal remodeling and esophageal dysmotility. We aimed to define and evaluate phenotypes of EoE using functional lumen imaging probe (FLIP) panometry (ie, a PhysioMechanical classification of EoE)., Methods: Patients with EoE who completed FLIP during endoscopy were included in a cross-sectional study. FLIP studies were analyzed for distensibility plateau and compliance of the esophageal body, maximum esophagogastric junction diameter, and contractile response pattern. These FLIP features were then applied to define PhysioMechanical classifications., Results: A total of 215 patients with EoE (mean [standard deviation] age 38 [12] years; 31% female) were included. Seven PhysioMechanical classifications were identified that differed by various clinical characteristics, including symptom duration (P < .001) and Endoscopic EoE Reference Scores (EREFS) (P < .001). In particular, patients with "nonreactive fibrostenosis" (n = 14), had greater symptom duration (median [interquartile range] 20 [10-30] years) and more frequently had EREFS grade 2 or 3 ring scores (14 of 14 patients) than patients with a "normal" PhysioMechanical classification (symptom duration: 3 [1-8] years; 4 of 50 [8%] had EREFS grade 2 or 3 rings). In addition, among patients off treatment at cross-sectional evaluation (n = 46), there was a difference between PhysioMechanical classifications in future proton pump inhibitor (PPI) response rates (ie, achieving peak mucosal eosinophil count <15 per high-powered field after PPI treatment); P = .009. PPI response ranged from 87% (13 of 15 patients) with "isolated esophagogastric junction outflow obstruction" to 11% (1 of 9 patients) with "spastic-reactive fibrostenosis.", Conclusions: Classifying PhysioMechanical esophageal function in EoE based on FLIP panometry features may facilitate defining disease severity and directing management in EoE., (Copyright © 2023 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Introduction: High-resolution manometry (HRM) and functional lumen imaging probe (FLIP) are primary and/or complementary diagnostic tools for the evaluation of esophageal motility. We aimed to assess the interrater agreement and accuracy of HRM and FLIP interpretations., Methods: Esophageal motility specialists from multiple institutions completed the interpretation of 40 consecutive HRM and 40 FLIP studies. Interrater agreement was assessed using intraclass correlation coefficient (ICC) for continuous variables and Fleiss' κ statistics for nominal variables. Accuracies of rater interpretation were assessed using the consensus of 3 experienced raters as the reference standard., Results: Fifteen raters completed the HRM and FLIP studies. An excellent interrater agreement was seen in supine median integral relaxation pressure (ICC 0.96, 95% confidence interval 0.95-0.98), and a good agreement was seen with the assessment of esophagogastric junction (EGJ) outflow, peristalsis, and assignment of a Chicago Classification version 4.0 diagnosis using HRM (κ = 0.71, 0.75, and 0.70, respectively). An excellent interrater agreement for EGJ distensibility index and maximum diameter (0.91 [0.90-0.94], 0.92 [0.89-0.95]) was seen, and a moderate-to-good agreement was seen in the assignment of EGJ opening classification, contractile response pattern, and motility classification (κ = 0.68, 0.56, and 0.59, respectively) on FLIP. Rater accuracy for Chicago Classification version 4.0 diagnosis on HRM was 82% (95% confidence interval 78%-84%) and for motility diagnosis on FLIP Panometry was 78% (95% confidence interval 72%-81%)., Discussion: Our study demonstrates high levels of interrater agreement and accuracy in the interpretation of HRM and FLIP metrics and moderate-to-high levels for motility classification in FLIP, supporting the use of these approaches for primary or complementary evaluation of esophageal motility disorders., (Copyright © 2023 by The American College of Gastroenterology.)

Background: Panesophageal pressurization (PEP) defines type II achalasia on high-resolution-manometry (HRM) but some patients exhibit spasm after treatment. The Chicago Classification (CC) v4.0 proposed high PEP values as predictor of embedded spasm, yet supportive evidence is lacking., Methods: Fifty seven type II achalasia patients (47 ± 18 years, 54% males) with HRM and LIP Panometry before and after treatment were retrospectively identified. Baseline HRM and FLIP studies were analyzed to identify factors associated with post-treatment spasm, defined on HRM per CC v4.0., Results: Seven patients (12%) had spasm following treatment (peroral endoscopic myotomy 47%; pneumatic dilation [PD] 37%; laparoscopic Heller myotomy 16%). At baseline, greater median maximum PEP pressure (MaxPEP) values on HRM (77 vs 55 mmHg, p = 0.045) and spastic-reactive contractile response pattern on FLIP (43% vs 8%, p = 0.033) were more common in patients with post-treatment spasm while absent contractile response on FLIP was more common in patients without spasm (14% vs 66%, p = 0.014). The strongest predictor of post-treatment spasm was the percentage of swallows with MaxPEP ≥70 mmHg (best cut-off: ≥30%), with AUROC of 0.78. A combination of MaxPEP <70 mmHg and FLIP 60 mL pressure < 40 mmHg identified patients with lower rates of post-treatment spasm (3% overall, 0% post-PD) compared to those with values above these thresholds (33% overall, 83% post-PD)., Conclusions: High maximum PEP values, high FLIP 60 mL pressures and contractile response pattern on FLIP Panometry prior to treatment identified type II achalasia patients more likely to exhibit post-treatment spasm. Evaluating these features may guide personalized patient management., (© 2023 The Authors. Neurogastroenterology & Motility published by John Wiley & Sons Ltd.)

New Findings: What is the central question of this study? DAPK3 contributes to the Ca 2+ -sensitization of vascular smooth muscle contraction: does this protein kinase participate in the myogenic response of cerebral arteries? What is the main finding and its importance? Small molecule inhibitors of DAPK3 effectively block the myogenic responses of cerebral arteries. HS38-dependent changes to vessel constriction occur independent of LC20 phosphorylation, and therefore DAPK3 appears to operate via the actin cytoskeleton. A role for DAPK3 in the myogenic response was not previously reported, and the results support a potential new therapeutic target in the cerebrovascular system., Abstract: The vascular smooth muscle (VSM) of resistance blood vessels is a target of intrinsic autoregulatory responses to increased intraluminal pressure, the myogenic response. In the brain, the myogenic reactivity of cerebral arteries is critical to homeostatic blood flow regulation. Here we provide the first evidence to link the death-associated protein kinase 3 (DAPK3) to the myogenic response of rat and human cerebral arteries. DAPK3 is a Ser/Thr kinase involved in Ca 2+ -sensitization mechanisms of smooth muscle contraction. Ex vivo administration of a specific DAPK3 inhibitor (i.e., HS38) could attenuate vessel constrictions invoked by serotonin as well as intraluminal pressure elevation. The HS38-dependent dilatation was not associated with any change in myosin light chain (LC20) phosphorylation. The results suggest that DAPK3 does not regulate Ca 2+ sensitization pathways during the myogenic response of cerebral vessels but rather operates to control the actin cytoskeleton. A slow return of myogenic tone was observed during the sustained ex vivo exposure of cerebral arteries to HS38. Recovery of tone was associated with greater LC20 phosphorylation that suggests intrinsic signalling compensation in response to attenuation of DAPK3 activity. Additional experiments with VSM cells revealed HS38- and siDAPK-dependent effects on the actin cytoskeleton and focal adhesion kinase phosphorylation status. The translational importance of DAPK3 to the human cerebral vasculature was noted, with robust expression of the protein kinase and significant HS38-dependent attenuation of myogenic reactivity found for human pial vessels., (© 2023 The Authors. Experimental Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.)

Background: Functional lumen imaging probe (FLIP) Panometry is performed at the time of sedated endoscopy and evaluates esophageal motility in response to distension. This study aimed to develop and test an automated artificial intelligence (AI) platform that could interpret FLIP Panometry studies., Methods: The study cohort included 678 consecutive patients and 35 asymptomatic controls that completed FLIP Panometry during endoscopy and high-resolution manometry (HRM). "True" study labels for model training and testing were assigned by experienced esophagologists per a hierarchical classification scheme. The supervised, deep learning, AI model generated FLIP Panometry heatmaps from raw FLIP data and based on convolutional neural networks assigned esophageal motility labels using a two-stage prediction model. Model performance was tested on a 15% held-out test set (n = 103); the remainder of the studies were utilized for model training (n = 610)., Key Results: "True" FLIP labels across the entire cohort included 190 (27%) "normal," 265 (37%) "not normal/not achalasia," and 258 (36%) "achalasia." On the test set, both the Normal/Not normal and the achalasia/not achalasia models achieved an accuracy of 89% (with 89%/88% recall, 90%/89% precision, respectively). Of 28 patients with achalasia (per HRM) in the test set, 0 were predicted as "normal" and 93% as "achalasia" by the AI model., Conclusions: An AI platform provided accurate interpretation of FLIP Panometry esophageal motility studies from a single center compared with the impression of experienced FLIP Panometry interpreters. This platform may provide useful clinical decision support for esophageal motility diagnosis from FLIP Panometry studies performed at the time of endoscopy., (© 2023 The Authors. Neurogastroenterology & Motility published by John Wiley & Sons Ltd.)

The esophagogastric junction (EGJ) is located at the distal end of the esophagus and acts as a valve allowing swallowed food to enter the stomach and preventing acid reflux. Irregular weakening or stiffening of the EGJ muscles results in changes to its opening and closing patterns which can progress into esophageal disorders. Therefore, understanding the physics of the opening and closing cycle of the EGJ can provide mechanistic insights into its function and can help identify the underlying conditions that cause its dysfunction. Using clinical functional lumen imaging probe (FLIP) data, we plotted the pressure-cross-sectional area loops at the EGJ location and distinguished two major loop types-a pressure dominant loop and a tone dominant loop. In this study, we aimed to identify the key characteristics that define each loop type and determine what causes the inversion from one loop to another. To do so, the clinical observations are reproduced using 1D simulations of flow inside a FLIP device located in the esophagus, and the work done by the EGJ wall over time is calculated. This work is decomposed into active and passive components, which reveal the competing mechanisms that dictate the loop type. These mechanisms are esophageal stiffness, fluid viscosity, and the EGJ relaxation pattern., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Description: The purpose of this American Gastroenterological Association (AGA) Institute Clinical Practice Update is to review the available evidence and expert advice regarding the clinical management of patients with suspected extraesophageal gastroesophageal reflux disease., Methods: This article provides practical advice based on the available published evidence including that identified from recently published reviews from leading investigators in the field, prospective and population studies, clinical trials, and recent clinical guidelines and technical reviews. This best practice document is not based on a formal systematic review. The best practice advice as presented in this document applies to patients with symptoms or conditions suspected to be related to extraesophageal reflux (EER). This expert review was commissioned and approved by the AGA Institute Clinical Practice Updates Committee (CPUC) and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership and underwent internal peer review by the CPUC and external peer review through standard procedures of Clinical Gastroenterology and Hepatology. These Best Practice Advice (BPA) statements were drawn from a review of the published literature and from expert opinion. Because systematic reviews were not performed, these BPA statements do not carry formal ratings of the quality of evidence or strength of the presented considerations. BEST PRACTICE ADVICE 1: Gastroenterologists should be aware of potential extraesophageal manifestations of gastroesophageal reflux disease (GERD) and should inquire about such disorders including laryngitis, chronic cough, asthma, and dental erosions in GERD patients to determine whether GERD may be a contributing factor to these conditions. BEST PRACTICE ADVICE 2: Development of a multidisciplinary approach to extraesophageal (EER) manifestations is an important consideration because the conditions are often multifactorial, requiring input from non-gastroenterology (GI) specialties. Results from diagnostic testing (ie, bronchoscopy, thoracic imaging, laryngoscopy, etc) from non-GI disciplines should be taken into consideration when gastroesophageal reflux (GER) is considered as a cause for extraesophageal symptoms. BEST PRACTICE ADVICE 3: Currently, there is no single diagnostic tool that can conclusively identify GER as the cause of EER symptoms. Determination of the contribution of GER to EER symptoms should be based on the global clinical impression derived from patients' symptoms, response to GER therapy, and results of endoscopy and reflux testing. BEST PRACTICE ADVICE 4: Consideration should be given toward diagnostic testing for reflux before initiation of proton pump inhibitor (PPI) therapy in patients with potential extraesophageal manifestations of GERD, but without typical GERD symptoms. Initial single-dose PPI trial, titrating up to twice daily in those with typical GERD symptoms, is reasonable. BEST PRACTICE ADVICE 5: Symptom improvement of EER manifestations while on PPI therapy may result from mechanisms of action other than acid suppression and should not be regarded as confirmation for GERD. BEST PRACTICE ADVICE 6: In patients with suspected extraesophageal manifestation of GERD who have failed one trial (up to 12 weeks) of PPI therapy, one should consider objective testing for pathologic GER, because additional trials of different PPIs are low yield. BEST PRACTICE ADVICE 7: Initial testing to evaluate for reflux should be tailored to patients' clinical presentation and can include upper endoscopy and ambulatory reflux monitoring studies of acid suppressive therapy. BEST PRACTICE ADVICE 8: Testing can be considered for those with an established objective diagnosis of GERD who do not respond to high doses of acid suppression. Testing can include pH-impedance monitoring while on acid suppression to evaluate the role of ongoing acid or non-acid reflux. BEST PRACTICE ADVICE 9: Alternative treatment methods to acid suppressive therapy (eg, lifestyle modifications, alginate-containing antacids, external upper esophageal sphincter compression device, cognitive-behavioral therapy, neuromodulators) may serve a role in management of EER symptoms. BEST PRACTICE ADVICE 10: Shared decision-making should be performed before referral for anti-reflux surgery for EER when the patient has clear, objectively defined evidence of GERD. However, a lack of response to PPI therapy predicts lack of response to anti-reflux surgery and should be incorporated into the decision process., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Diagnosis and management of chronic esophageal disease requires the use of potentially traumatic medical procedures, performed with or without sedation. Medical trauma and post-traumatic stress (PTS) are emerging as important considerations in patients with digestive illness. To date, no study assesses medical PTS from procedures in patients with esophageal disease., Methods: Adult patients with achalasia, eosinophilic esophagitis, gastroesophageal reflux disease, or functional esophageal disease at a university-based gastroenterology clinic completed: Post-Traumatic Stress Disorder Checklist for DSM-5 (PCL-5), Gastroesophageal Disease Questionnaire, Brief Esophageal Dysphagia Questionnaire, Northwestern Esophageal Quality of Life scale (HRQoL), NIH-PROMIS Depression scale, and a study-specific questionnaire about esophageal procedures (endoscopy with sedation; functional lumen imaging probe (FLIP) with sedation; high-resolution manometry (HRM); wireless pH testing; or 24-h pH-impedance testing)., Key Results: Half of 149 participants reported at least one traumatic procedure, with HRM most often cited. Only 2.7% met the cutoff for PTS on PCL-5. This increased to 7.1% for patients with a traumatic procedure combined with experiencing intense fear. Rates of moderate-severe PTS ranged from 7.4%-12% for all patients and 14%-29% for those with a traumatic procedure with fear. Medical PTS was associated with poorer HRQoL, and increased esophageal symptoms, depression, and hypervigilance and symptom anxiety., Conclusions & Inferences: Preliminary evidence suggests medical PTS affects few patients with esophageal disease. However traumatic procedures, most often associated with HRM, significantly increase PTS symptoms. The potential impacts of medical PTS on esophageal patient assessment and outcomes are considerable and warrants further study., (© 2023 The Authors. Neurogastroenterology & Motility published by John Wiley & Sons Ltd.)

Background: Eosinophilic esophagitis (EoE) is associated with fibrostenotic remodeling that can be objectively assessed using the functional lumen imaging probe (FLIP). This is typically done using a metric called distensibility plateau (DP). We aimed to describe a novel measure of compliance of the esophageal body and evaluate the associated clinical characteristics in EoE., Methods: One hundred seventy-one adult patients with EoE (mean (SD) age 38 (12) years), 31% female and 35 healthy, asymptomatic controls who completed 16-cm functional luminal imaging probe (FLIP) during endoscopy, were evaluated in a cross-sectional study. The esophageal body DP and compliance were measured using a customized analysis program, with compliance calculated as (Δ esophageal body volume)/(Δ pressure) between two FLIP-filled volumes., Results: In controls, the median (5-95th percentile) DP was 19.8 mm (17.9-21) and esophageal body compliance was 0.37 ml/mmHg (0.18-1.1), which was greater than in EoE (DP 19 (11-21)), compliance 0.19 (0.02-0.71), p-values <0.001. Among EoE patients, 70 (41%) had normal compliance (>0.2 ml/mmHg) and normal DP (>17 mm); 11 (6%) had normal compliance and reduced DP; 34 (20%) had reduced compliance and normal DP; and 56 (33%) had reduced compliance and reduce DP. Patients with both reduced compliance and DP had the greatest proportion of severe rings (61% with EREFS score 2-3) and stricture (100%)., Conclusion: FLIP provides an objective evaluation of biomechanical properties of the esophageal wall that appears enhanced by complementary application of metrics of DP and esophageal body compliance., (© 2023 John Wiley & Sons Ltd.)

Background: The functional lumen imaging probe (FLIP) evaluates esophagogastric junction (EGJ) opening and esophageal contractility. Both post hoc and real-time analyses are possible, but reproducibility and reliability of analysis remain undefined. This study assesses inter- and intra-rater agreement of normative FLIP measurements among novice and experienced users., Methods: Eight motility experts from different institutions independently evaluated de-identified video recordings from 27 asymptomatic healthy subjects using FLIP. Interpretation methods simulating a post-procedure and a live procedure setting were tested. Novice FLIP users (n = 3) received training prior to post-procedure interpretation. Experienced FLIP users (n = 5) interpreted using both methods. Users recorded maximum EGJ and distal esophageal body diameter, distensive pressure, and EGJ distensibility index (EGJ-DI), at balloon fill volumes of 50-, 60-, and 70 ml, as well as repetitive antegrade contractions (RACs). Inter- and intra-rater agreements of diameters, distensive pressure and EGJ-DI were assessed by intra-class correlation coefficient (ICC) and Pearson's correlation coefficient (PCC). Percentage agreement evaluated inter- and intra-rater reliability for RACs., Key Results: Novice and experienced users acquired normative FLIP metrics. Good-to-excellent inter- and intra-rater reliability were achieved for all variables at 60 ml balloon fill volumes. Median parameters at 60 ml balloon fill volume were as follows: EGJ-DI 5.5 mm 2 /mmHg, maximum EGJ diameter 18.6 mm, distensive pressure at maximum EGJ diameter 48.1 mmHg, and distal esophageal body diameter 19.5 mm., Conclusions and Inferences: Normative FLIP parameters can be reliably extracted from FLIP videos using both real-time and post hoc analyses, with high reliability between experienced and novice users., (© 2022 John Wiley & Sons Ltd.)

A FLIP device gives cross-sectional area along the length of the esophagus and one pressure measurement, both as a function of time. Deducing mechanical properties of the esophagus including wall material properties, contraction strength, and wall relaxation from these data are a challenging inverse problem. Knowing mechanical properties can change how clinical decisions are made because of its potential for in-vivo mechanistic insights. To obtain such information, we conducted a parametric study to identify peristaltic regimes by using a 1D model of peristaltic flow through an elastic tube closed on both ends and also applied it to interpret clinical data. The results gave insightful information about the effect of tube stiffness, fluid/bolus density and contraction strength on the resulting esophagus shape through quantitive representations of the peristaltic regimes. Our analysis also revealed the mechanics of the opening of the contraction area as a function of bolus flow resistance. Lastly, we concluded that peristaltic driven flow displays three modes of peristaltic geometries, but all physiologically relevant flows fall into two peristaltic regimes characterized by a tight contraction., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)