Functional Lumen Imaging Probe Research Articles

Utility of Esophageal Physiologic Tests in Eosinophilic Esophagitis

Background: In patients with eosinophilic esophagitis (EoE), the correlation between symptoms of esophageal dysfunction and endoscopic and histologic disease activity is generally poor and probably related to multiple causes such as esophageal remodeling processes that might go undetected using endoscopy and histology as well as esophageal hypervigilance and symptom-specific anxiety. Hence, there is a need for a holistic management of patients that goes beyond the control of eosinophilia and symptoms. Summary & Key messages: Physiological esophageal testing using high-resolution manometry, functional lumen imaging probe, pH-impedance, wireless pH monitoring and mucosal impedance may unveil the effects of chronic transmural fibro-inflammatory changes of the esophageal wall as well as esophageal hypervigilance, thereby assisting to phenotype patients, predict therapeutic response to therapy and identify motility disorders that may need a specific targeted therapy to ameliorate patients’ outcomes. This article discusses the role of functional esophageal examinations in the diagnosis and management of EoE.

ENDOSCOPIC SEDATION TYPE DURING FLIP PANOMETRY DOES NOT SIGNIFICANTLY IMPACT FLIP MOTILITY CLASSIFICATION RELATIVE TO MANOMETRY

Functional lumen imaging probe (FLIP) Panometry evaluates esophageal motility at the time of sedated endoscopy and often parallels high-resolution manometry (HRM) performed in awake patients. This study aimed to assess the impact of endoscopic sedation on FLIP evaluation of esophageal motility. Adult patients who completed FLIP Panometry during sedated endoscopy and had a conclusive Chicago Classification v4.0 diagnosis on HRM were included in this retrospective study. HRM diagnoses relative to FLIP Panometry motility classifications were compared by sedation type used during FLIP, i.e. conscious sedation (CS) with midazolam and fentanyl or monitored anesthesia care (MAC) with propofol. 454 patients (mean (SD) age 53 (17) years, 62% female) completed FLIP Panometry under CS (n=174, 38%) or MAC (n=280, 62%; 177/280 MAC included fentanyl). On comparison of CS vs MAC, HRM diagnoses within FLIP Panometry motility classifications did not differ (P=0.306 across all 5 FLIP Panometry classifications; P values 0.202-0.856 within specific FLIP classifications). The proportion of HRM diagnoses within each FLIP Panometry classification also did not differ between FLIP completed with CS vs MAC with fentanyl (P=0.098) or MAC without fentanyl (P=0.0261) CONCLUSIONS: Whether CS or MAC was used as sedation during FLIP did not have a clinically significant impact on the relationship between diagnosis on FLIP Panometry and HRM. This supports the validity of diagnosing esophageal motility disorders using FLIP Panometry during sedated endoscopy.

Achalasia: beyond the basics

Achalasia is a rare oesophageal disease characterised by an unrelaxing lower oesophageal sphincter and abnormal peristalsis of the oesophageal body. Achalasia symptoms include dysphagia to solid and liquid, chest pain, regurgitation and weight loss. Achalasia diagnosis might be delayed for many years when atypical symptoms dominate. Significant progress has been made over the last two decades regarding our understanding of pathophysiology, methods of evaluation and management. The development of high-resolution manometry in particular has improved the diagnosis of achalasia, as well as other major motility disorders. Subtyping achalasia into manometric patterns has pathophysiological and therapeutic implications. Furthermore, complementary tests such as timed barium swallow and the functional lumen imaging probe (EndoFLIP; Crospon Medical Devices, Galway, Ireland) have significantly added to achalasia diagnosis algorithm and management decision-making. Progression in management has helped optimise established therapy (pneumatic dilatation and Heller myotomy) and introduced new endoscopic treatments (peroral endoscopic myotomy) and surgical techniques (surgical robotic Heller myotomy). This review will aim to shed light on the most recent advances in achalasia diagnosis, classification and management.

Four-Dimensional Impedance Manometry in Esophageal Motility Disorders.

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. 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. 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. 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.

Defining lower esophageal sphincter physiomechanical states among esophageal motility disorders using functional lumen imaging probe panometry.

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. 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. 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. 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.

772. EVALUATING OUTCOMES OF LES OBSTRUCTION AND REFLUX IN PATIENTS UNDERGOING PERORAL ENDOSCOPIC MYOTOMY GUIDED BY THE 16CM IMPEDANCE PLANIMETRY CATHETER

Abstract Background Peroral endoscopic myotomy (POEM) is a standard treatment option in achalasia. The endoluminal functional lumen imaging probe (FLIP) system utilizes impedance planimetry to measure diameter and distensibility at the esophagogastric junction (EGJ) in real-time. Most reports of the intraoperative FLIP experience focus on the 8 cm balloon, but the 16 cm balloon catheter also provides topographical assessments in addition to EGJ metrics. The aim of this study is to determine the clinical outcomes after a tailored myotomy using the 16 cm balloon during POEM. Methods We conducted a retrospective review of consecutive patients who underwent POEM with intraoperative FLIP with the 16 cm balloon catheter between January 2020 and September 2023. Operative reports were reviewed, and data including FLIP metrics and topographical assessments and myotomy length, which was guided by FLIP panometry, were recorded. Clinical parameters for lower esophageal sphincter (LES) obstruction (defined by FLIP-EGJ metrics, BEDQ/Eckardt scores and/or need for LES re-intervention) and reflux (defined by GERD-HRQL/RSI scores, +pH testing, LA B/C/D reflux esophagitis, PPI use and/or need for anti-reflux surgery) were collected during the 6-36 month follow up time period. Results Of 100 patients (57 female, mean 56.1y), 82 had Achalasia, 15 EGJOO, and 3 hypercontractile esophagus. Myotomy length was tailored (mean 8.2cm, range 3 – 15) by FLIP, and 10% had a short myotomy (≤4cm). Among 16 patients with previous Heller, the myotomy targeted contractile activity proximal to the previous myotomy in 10 cases. On follow up of 71 patients (median time 14mo), clinical outcomes are noted in Table 1. Obstructive symptoms and FLIP metrics showed significant improvement. Repeat myotomy was required in 5.6%. While reflux symptom scores improved, 37.5% had abnormal %AET, 4.7% had reflux esophagitis, and 7.0% required anti-reflux surgery. Conclusion A tailored myotomy with guidance of a 16 cm FLIP catheter to assess EGJ metrics and topographical assessments during POEM appears to be safe and effective at 6-36 month follow up. A tailored myotomy allows for a shorter myotomy than traditional surgical lengths and can be extended to capture residual disease noted with the 16 cm FLIP catheter in patients with previous surgery. Use of the 16 cm balloon during POEM results in overall low rates of LES re-intervention and post-myotomy reflux.

Application of Functional Lumen Imaging Probe in the Evaluation and Treatment of Anorectal Strictures

Application of Functional Lumen Imaging Probe in the Evaluation and Treatment of Anorectal Strictures

497. ENDOFLIP AND BOTULIN TOXIN INJECTION: THERAPEUTIC MANAGEMENT IN ESOPHAGEAL AND GASTRIC MOTILITY DISORDERS

Abstract Introduction Esophageal motility disorders present diagnostic and therapeutic challenges, with dysphagia being a common symptom prompting evaluation. The Endolumenal Functional Lumen Imaging Probe (EndoFLIP) has recently gained recognition as a valuable tool for assessing esophageal function. This study aims to evaluate the utility of EndoFLIP in guiding therapeutic interventions, specifically focusing on botulinum toxin injections, among patients presenting with diverse esophageal disorders. Moreover, the study acknowledges the potential of EndoFLIP as a diagnostic adjunct during diagnostic upper gastrointestinal endoscopy in cases where therapeutic alternatives are limited or as therapeutic trial. Methods A retrospective analysis was conducted on 21 patients who underwent EndoFLIP assessment and subsequently received botulinum toxin injection at the same procedure. These patients were identified from records at a tertiary center, covering the period from January 2022 to February 2023. EndoFLIP procedures were analyzed, focusing on patient symptoms and indication for the procedure. Data regarding clinical symptoms, EndoFLIP findings, and therapeutic interventions were extracted and analyzed to assess the role of EndoFLIP in guiding treatment decisions for esophageal disorders. The used cutoffs for esophagogastric junction (EGJ) distensibility index were &amp;lt; 2 mm2/mmHg and &amp;lt; 10 mm2/mmHg for pyloric distensibility. Results All patients referred for esophageal motility evaluation with EndoFLIP presented with dysphagia as the primary symptom. Two patients presented with postprandial bloating, leading to further evaluation with impedance planimetry to assess pyloric distensibility, suspected to be due to diabetic gastroparesis. Following EndoFLIP assessment, a conclusive diagnosis was achieved in all patients: 10 patients were diagnosed with esophagogastric junction outflow obstruction, 1 patient with absent contractility, 7 patients with achalasia, and 1 patient with hypercontractile esophagus. Patients who underwent planimetry to evaluate pyloric distensibility both exhibited reduced distensibility index. Following treatment, 10 patients showed clinical improvement and 11 await clinical reassessment. Conclusions Regarding the evaluation of the EGJ distensibility index in patients with achalasia without indication for invasive treatment, the EndoFLIP emerges as a diagnostic tool that allows for immediate guidance if intervention is recommended. Likewise, patients with refractory gastroparesis and pylorospasm identified through EndoFLIP may benefit from toxin injection for future myotomy decision. In conclusion, EndoFLIP serves as a valuable tool in diagnosing and guiding therapeutic interventions in patients with esophageal and gastric motility disorders. Further research is warranted to validate the role of EndoFLIP in optimizing treatment outcomes for esophageal disorders.

371. ENDOFLIP: THE FUTURE OF DYSPHAGIA DIAGNOSIS AND MANAGEMENT

Abstract Background High-resolution manometry (HRM) is the gold standard for characterizing esophageal motility disorders, but it’s frequently associated with poor patient tolerance. A newer diagnostic tool, the Endoscopic Functional Lumen Imaging Probe (EndoFLIP), has emerged to assess esophagogastric junction (EGJ) distensibility and distension-mediated peristalsis. Also, for motility disorders such as EGJ outflow obstruction (EGJOO), HRM-isolated features aren’t enough for the diagnosis. The diagnosis also requires symptom correlation and additional investigations like EndoFLIP. Methods We conducted a single-center prospective cohort study for patients with dysphagia and inconclusive or intolerant to HRM. The inclusion criteria were patients with an elevated median integrated relaxation pressure (IRP) on HRM and patients with an inconclusive or intolerant to HRM. Patients with isolated IRP on HRM were included, as this isolated finding does not allow for the definitive diagnosis of EGJOO. These patients underwent EndoFLIP testing from January 2022 to February 2024 at a tertiary center. Results We performed EndoFLIP on 42 patients (50% male; 50% female), 23,8% with EGJOO diagnosis on HRM, 21,4% with inconclusive HRM, and 54,8% patients intolerant to HRM. Twenty-three patients intolerant to HRM underwent EndoFLIP, enabling diagnosis in all cases. Four patients were diagnosed with EGJOO, 6 with achalasia, and 4 with ineffective esophageal motility (IEM). On 88% of patients, the EndoFLIP allowed a correct diagnosis and treatment, with 29% undergoing endoscopic treatment during the same procedure. 9 patients with inconclusive HRM were diagnosed after EndoFLIP: 3 were diagnosed with EGJOO, 4 with IEM, and 3 with achalasia. We report a significant discordance between EGJOO diagnosis on HRM and EndoFLIP results. 50% of patients diagnosed with EGJOO on HRM showed normal EndoFLIP results, with only 20% confirming the diagnosis, while 20% raised the possibility of the diagnosis being achalasia. 43,8% of patients diagnosed with EGJOO confirmed by EndoFLIP underwent endoscopic therapy with botulinum toxin or balloon dilation during the same procedure, resulting in clinical improvement for all patients. Discussion The discordance between HRM and EndoFLIP may arise from HRM's tendency to overdiagnose EJGOO, leading to unnecessary testing and treatments for EGJOO. Many EGJOO HRM diagnoses don't require therapy, as symptoms often resolve spontaneously or with dietary education, casting doubt on the isolated HRM finding's clinical significance. It's particularly beneficial for patients with inconclusive/intolerance to HRM, allowing correct diagnosis and treatment in cases of obstructive symptoms. These results support EndoFLIP as a screening tool for patients undergoing endoscopy, enabling better selection of those benefiting from subsequent HRM.

Association of gastric myotomy length in peroral endoscopic myotomy (POEM) with gastro-esophageal junction distensibility measured by Endoluminal Functional Lumen Imaging Probe (EndoFLIP).

Endoluminal Functional Lumen Imaging Probe (EndoFLIP) is a device that measures gastro-esophageal junction (GEJ) distensibility. However, it is not demonstrated that GEJ distensibility increases proportionally with varying gastric myotomy length in peroral endoscopic myotomy (POEM). This study aimed to investigate the association between gastric myotomy length in POEM and intraoperative EndoFLIP findings. This single-center, retrospective cohort study included patients who underwent POEM with intraoperative EndoFLIP from December 2019 to January 2023. Using EndoFLIP, minimal balloon diameter and its distensibility index (DI) were measured pre- and post-myotomy. Primary and secondary outcomes were the post-myotomy EndoFLIP findings at 30ml and 40ml volume fills. The study included 44 patients (mean age 53.1years, 50% female). Chicago classification included achalasia type I (39%), II (41%), III (9%), hypercontractile esophagus (2%), and EGJOO (9%). The mean esophageal myotomy length was 7.5 ± 2.2cm and gastric myotomy was 2.1 ± 0.6cm. Simple linear regression analyses indicated that for each 1cm increase in gastric myotomy length, the DI at 30ml volume fill was estimated to increase by 2.0mm2/mmHg (p < 0.05, R2 = 0.41), the minimal diameter at 30ml volume fill was estimated to increase by 2.4mm (p < 0.05, R2 = 0.48), and the minimal diameter at 40ml volume fill was estimated to increase by 1.3mm (p < 0.05, R2 = 0.09). This study demonstrates a significant linear relationship between gastric myotomy length and GEJ distensibility measured by EndoFLIP during POEM. These findings may be useful in clinical practice by enabling EndoFLIP to help calibrate a desired gastric myotomy length to achieve optimal DI and minimal diameter.

Perioperative management protocol for pediatric endoluminal functional lumen imaging probe in esophageal motility disorders.

Lower esophageal sphincter achalasia is associated with a higher risk of aspiration during anesthesia. Endoluminal Functional Lumen Imaging Probe (EndoFLIP) is used as an adjunctive tool in both the diagnosis and treatment of achalasia, for which all children require anesthesia. Anesthesia may affect the parameters of the EndoFLIP due to its effect on gut motility. There are no standard anesthesia protocols to help decrease the risk of aspiration and the undesirable effect of anesthesia on EndoFLIP parameters. This study aims to standardize an anesthesia protocol to target both goals. A protocol was developed to address perioperative management in patients undergoing EndoFLIP for any indication to minimize both anesthetic effect on the esophageal motility as well as perioperative complications. A retrospective data analysis was conducted on patients who underwent EndoFLIP at Cincinnati Children's Hospital Medical Center; pre- and post-protocol implementation data including adverse events was compared. Pre-protocol implementation: 60 cases (median age of 13.8 years, 30 [50%] females) with 2 cases of adverse events (3.3%). Post-protocol implementation: 71 cases (median age of 14.6 years, 37 [52.1%] females) with no adverse events (0/71 = 0%). In comparison between pre- and post-protocol cases, no significant difference was noted in gender, age, and adverse events. Post-protocol procedures were found to be significantly shorter (median time of 89 vs. 79 min, p = 0.004). Our anesthesia protocol provides a standardized way of administering anesthesia minimizing impact on EndoFLIP parameters and aspiration for patients with achalasia.

Functional lumen imaging probe use in a high-volume practice: Practical and technical implications.

The functional lumen imaging probe (FLIP) is a Food and Drug Administration approved tool to aid the diagnosis and management of esophageal disorders. However, widespread adoption of FLIP remains limited and its utility in high-volume practices remains unclear. To analyze large sample data on clinical use of FLIP and provide insight on several technical aspects when performing FLIP. We conducted a retrospective comparative and descriptive analysis of FLIP procedures performed by a single provider at an academic medical center. There was a total of 398 FLIP procedures identified. Patient medical records were reviewed and data regarding demographics and procedural details were collected. Statistical tests, including chi-squared, t-test, and multivariable logistic and linear regression, were performed. There was an increase in FLIP cases with each successive time period of 13 months (n = 68, 146, 184, respectively) with notable rises specifically for indications of dysphagia and gastroesophageal reflux disease. There was a shift toward use of the longer FLIP balloon catheter for diagnostic purposes (overall 70.4% vs 29.6%, P < 0.01). Many cases (42.8%) were performed in conjunction with other diagnostics/interventions, such as dilation and wireless pH probe placement. Procedures were nearly equally performed with anesthesia vs moderate sedation (51.4% anesthesia), with no major complications. Patients who had anesthesia were less likely to have recurrent antegrade contractions [odds ratio (OR) = 0.4, 95%CI: 0.3-0.8] and were also more likely to have absent contractility (OR = 2.4, 95%CI: 1.3-4.4). FLIP cases have increased in our practice with expanding indications for its use. Given limited normative data, providers should be aware of several potential technical issues, including the possible impact of sedation choice when assessing esophageal motility patterns.

The functional lumen imaging probe contractile response pattern is the best predictor of botulinum toxin response in esophagogastric junction outflow obstruction.

Esophagogastric junction outflow obstruction (EGJOO) is a heterogenous disorder in which the correct management strategy is unclear. We assessed whether functional lumen imaging probe (FLIP) topography data could select EGJOO, which would benefit from lower esophageal sphincter Botulinum toxin (Botox) injection. This was a single-center prospective study of adult patients meeting Chicago Classification (CC) v3.0 criteria for EGJOO. We assessed differences in pretreatment physiologic measurements on high-resolution manometry (HRM) and FLIP and other relevant clinical variables in predicting Botox response (>50% in BEDQ at 2 months). Sixty-nine patients were included (ages 33-90, 73.9% female). Of these, 42 (61%) were Botox responders. Majority of physiologic measures on HRM and FLIP and esophageal emptying were not different based on Botox response. However, a spastic-reactive (SR) FLIP contractile response (CR) pattern predicted a Botox response with OR 25.6 (CI 2.9-229.6) when compared to antegrade FLIP CR; and OR for impaired-disordered/absent CR was 22.5 (CI 2.5-206.7). Logistic regression model using backward elimination (p value = 0.0001, AUC 0.79) showed that a SRCR or IDCR/absent response and the upright IRP predicted Botox response. Response rates in tiered diagnostic groups were: (i) CCv3.0 EGJOO (60.9%), (ii) CCv4.0 EGJOO (73.1%), (iii) CCv4.0 + FLIP REO (80%), (iv) CCv4.0, FLIP REO, and abnormal FLIP CR (84.2%), and (v) CCv4.0, FLIP REO, and SR FLIP CR (90%). FLIP helps identify patients with EGJOO who are likely to response to LES Botox therapy. An abnormal FLIP contractile response pattern is the single-most important predictor of a Botox response.

Utilizing Esophageal Motility Tests in Diagnosing and Evaluating Gastroesophageal Reflux Disease.

Gastroesophageal reflux disease (GERD), a prevalent clinical condition, is often attributed to aberrant esophageal motility, leading to gastric content reflux and associated symptoms or complications. The rising incidence of GERD presents an escalating healthcare challenge. Endoscopic and esophageal reflux monitoring can provide a basis for the diagnosis of patients with gastroesophageal reflux disease, but when the diagnostic basis is at an inconclusive value, some additional supportive evidence will be needed. Advanced technology is the key to improving patient diagnosis, accurate assessment, and the development of effective treatment strategies. High-resolution esophageal manometry (HREM) and endoscopic functional lumen imaging probe (EndoFLIP) represent the forefront of esophageal motility assessment. HREM, an evolution of traditional esophageal manometry, is considered the benchmark for identifying esophageal motility disorders. Its widespread application in esophageal dynamics research highlights its diagnostic significance. Concurrently, EndoFLIP's emerging clinical relevance is evident in diagnosing and guiding the treatment of coexisting esophageal motility issues. This review integrates contemporary research to delineate the contributions of HREM, EndoFLIP, and novel technologies in GERD. It examines their efficacy in facilitating an accurate diagnosis, differentiating similar gastrointestinal disorders, quantifying the extent of reflux, assessing the severity of the disease, forecasting patient responsiveness to proton pump inhibitor therapy, and guiding decisions for surgical interventions. The overarching aim is to deepen the understanding of GERD's underlying mechanisms and advance the formulation of holistic, efficacious treatment approaches.

Optimal Assessment, Treatment, and Monitoring of Adults with Eosinophilic Esophagitis: Strategies to Improve Outcomes.

Eosinophilic esophagitis (EoE) is a chronic type 2 inflammation-mediated disease characterized by an eosinophil-predominant inflammation of the esophagus and symptoms of esophageal dysfunction. Relevant treatment outcomes in the setting of EoE include the improvement of histology, symptoms, and endoscopy findings, quality of life (QoL), and the psychological burden of the disease. Established validated tools for the assessment of EoE include questionnaires on dysphagia and QoL (ie, DSQ, EEsAI, and EoE-IQ). More recently, esophageal symptom-specific anxiety and hypervigilance, assessed using the esophageal hypervigilance and anxiety scale (EHAS), have emerged as contributors to disease burden, confirming the importance of psychological aspects in EoE patients. The EoE endoscopic reference score (EREFS) is the only validated endoscopy score in EoE and can quantify mucosal disease burden. However, esophageal panometry using the functional lumen imaging probe (FLIP) and high-resolution manometry (HRM) have shown potential to optimize the assessment of fibrostenotic features of EoE, providing novel insights into the pathophysiology of symptoms. There is a growing number of licenced and off-label therapeutic options in EoE, with various randomized controlled trials demonstrating the efficacy of proton pump inhibitors, topical steroids, food elimination diets, biological drugs, and esophageal dilatation. However, standardized optimal management strategies of EoE are currently lacking. In this review, we provide an overview of established and novel assessment tools in EoE including patient reported outcomes, FLIP panometry, HRM, endoscopy, and histology outcome measures to improve the outcomes of EoE patients. In addition, we summarize available therapeutic options for EoE based on the most recent evidence.

Enhancing Chicago Classification diagnoses with functional lumen imaging probe-mechanics (FLIP-MECH).

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. 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. 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. 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.

Age Affects Esophageal Secondary Peristalsis More Than Primary as Assessed by FLIP Panometry and High-resolution Manometry

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.

Discriminating "impaired" from "disordered" contractile response on FLIP panometry by utilizing pressure measurement.

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. 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. 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). 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.

Tailoring the wrap: intraoperative functional lumen imaging probe (FLIP) during hiatal hernia repair

IntroductionThe introduction of the functional lumen imaging probe (FLIP) has provided objective, real-time feedback on the geometric variations with each component of a hiatal hernia repair (HHR). The utility of this technology in altering intraoperative decision-making has been scarcely reported. Herein, we report a single-center series of intraoperative FLIP during HHR.MethodsA retrospective review of electronic medical records between 2020 and 2022 was conducted and all patients undergoing non-recurrent HHR with FLIP were queried. Patient and hernia characteristics, intraoperative FLIP values and changes in decision-making, as well as early post-operative outcomes were reported. Both diameter and distensibility index (DI) were measured at 40 ml and 50 ml balloon inflation after hiatal dissection, after hiatal closure, and after fundoplication when indicated.ResultsThirty-three patients met inclusion criteria. Mean age was 62 ± 14 years and mean BMI was 28 ± 6 kg/m2. The majority (53%) were type I hiatal hernias. The largest drop in DI occurred after hiatal closure, with minimal change seen after fundoplication (mean DI of 4.3 ± 2. after completion of HH dissection, vs 2.7 ± 1.2 after hiatal closure and 2.3 ± 1 after fundoplication when performed). In 13 (39%) of cases, FLIP values directly impacted intraoperative decision-making. Fundoplication was deferred in 4/13 (31%) patients, the wrap was loosened in 2/13 (15%); the type of fundoplication was altered to achieve adequate anti-reflux values in 2/13 (15%) patients, and in 1/13 (3%) the wrap was tightened.ConclusionFLIP measurements can be used intraoperatively to guide decision-making and alter management plan based on objective values. Long-term outcomes and further prospective studies are required to better delineate the value of this technology.

Efficacy and Safety of Gastric Per-Oral Endoscopic Myotomy (G-POEM): A Systematic Review and Meta-Analysis.

Gastric per-oral endoscopic myotomy (G-POEM) is an innovative treatment that has become increasingly utilized for patients with refractory gastroparesis. The aim of this systematic review and meta-analysis was to evaluate the safety and effectiveness of G-POEM for the treatment of gastroparesis. Individualized search strategies were developed through February 2021 in accordance with the PRISMA and MOOSE guidelines. This meta-analysis was performed by calculating pooled proportions and mean difference preprocedure and postprocedure with rates estimated using random effects models. Measured outcomes included technical success, clinical success, improvement in gastroparesis cardinal symptom index (GCSI), change in gastric emptying rate, alterations in impedance planimetry (functional lumen imaging probe [FLIP]) assessment, and adverse events. A total of 20 studies (n=797 patients; 67.41% female) were included. The mean age was 48.92±11.61 y, with an average duration of 4.24±1.11 y since gastroparesis diagnosis. Technical success was 98.47% [(95% CI: 97.14, 99.19);I2=0.00] with a mean myotomy length of 3.78±1.16cm. In terms of clinical success, mean preprocedure GCSI scores were 3.38±0.37 and improved significantly postprocedure [weighted mean difference -1.56 (95% CI: -1.89 to -1.24); I2=82.53; P<0.001]. Gastric retention after 4 hours demonstrated ~50% improvement (preprocedure 43.08±9.24% versus postprocedure 22.97±10.19%; P<0.001). FLIP assessment with 40mL and 50mL balloons demonstrated a significant increase in diameter, distensibility index, and cross-sectional area postprocedure (all P<0.05). Procedure-associated adverse events occurred among 10.92% [(95% CI 5.09 to 19.32); I2=82.85] of patients. G-POEM appears safe and highly effective for the treatment of patients with refractory gastroparesis regardless of symptom predominance or etiology.