Endolumenal Functional Lumen Imaging Probe Research Articles

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 < 2 mm2/mmHg and < 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.

Use of endolumenal functional lumen imaging probe in investigating paediatric gastrointestinal motility disorders.

Investigating gastrointestinal (GI) motility disorders relies on diagnostic tools to assess muscular contractions, peristalsis propagation and the integrity and coordination of various sphincters. Manometries are the gold standard to study the GI motor function but it is increasingly acknowledged that manometries do not provide a complete picture in relation to sphincters competencies and muscle fibrosis. Endolumenal functional lumen imaging probe (EndoFLIP) an emerging technology, uses impedance planimetry to measure hollow organs cross sectional area, distensibility and compliance. It has been successfully used as a complementary tool in the assessment of the upper and lower oesophageal sphincters, oesophageal body, the pylorus and the anal canal. In this article, we aim to review the uses of EndoFLIP as a tool to investigate GI motility disorders with a special focus on paediatric practice. The majority of EndoFLIP studies were conducted in adult patients but the uptake of the technology in paediatrics is increasing. EndoFLIP can provide a useful complementary data to the existing GI motility investigation in both children and adults.

The Outcomes of Performing Partial Fundoplication Based on Endoflip Versus Manometric Findings.

The surgical management of gastroesophageal reflux disease (GERD) involves extensive diagnostic studies and sophisticated surgical techniques. The workup should be comprehensive and purposeful. High resolution impedance manometry (HRIM) provides valuable information regarding peristalsis and lower esophageal sphincter relaxation. The disadvantages of HRIM such as intolerance or inability to pass the catheter led to its selective use or even omission especially in laparoscopic hiatal hernia repair with partial fundoplication. This pragmatic approach risks missing motility disorders in patients with secondary reflux symptoms related to achalasia or scleroderma. Endolumenal functional lumen imaging probe (endoFLIP) can fill this void as it evaluates the dynamics of the esophagogastric junction under sedation. This study aims to compare the outcomes of preoperative use of HRIM vs endoFLIP for laparoscopic repair of hiatal hernia with partial fundoplication. This is a retrospective cohort study for consecutive patients who underwent antireflux surgery with partial fundoplication between July 2018 and February 2021. Preoperative and postoperative outcomes were compared between two cohorts of patients: those with preoperative HRIM and those with preoperative endoFLIP. A total of 72 patients were evaluated, 41 had preoperative HRIM and 31 had endoFLIP. There was no statistically significant difference in their age, sex, BMI, duration of GERD symptoms, or proton pump inhibitors use. The endoscopic findings of esophagitis, hiatal hernia, and Hill's grade were comparable. There was no difference in the American Society of Anesthesiology classification or the choice of antireflux surgery. The improvement of postoperative GERD scores and dysphagia subscore was similar between the two groups. Performing partial fundoplication based on endoFLIP evaluation of the dynamics of the esophagogastric junction is safe and does not increase postoperative dysphagia compared to preoperative manometric use. Randomized prospective studies are needed to confirm the findings of this study.

An update on endoscopic treatment for achalasia: From per oral endoscopic myotomy to endolumenal functional lumen imaging probe

An update on endoscopic treatment for achalasia: From per oral endoscopic myotomy to endolumenal functional lumen imaging probe

S0358 Role of Endoscopic Functional Luminal Imaging Probe (EndoFLIP) for the Management of Post Myotomy Clinical Failure

INTRODUCTION: Peroral Endoscopic Myotomy (POEM) and Laparoscopic Heller myotomy (LHM) have evolved as effective management tools in relieving lower esophageal sphincter (LES) pressure in patients with esophageal motility disorders. However, a small percentage of patients fail to improve or relapse after time. The challenge remains in identifying the patients who might benefit from repeat myotomy as opposed to conservative managements. In the following study, we describe the role of endolumenal functional lumen imaging probe (EndoFLIP), in addition to high-resolution manometry (HRM), for managing such patients. METHODS: This was a multicenter, international retrospective study conducted between January 2015 and October 2019. Patients with a diagnosis of achalasia, esophagogastric junction outflow obstruction (EGJOO), diffuse esophageal spasm (DES), or jackhammer esophagus (JE) who underwent a prior failed myotomy were included. Clinical success of post repeat myotomy in the form of POEM was considered the primary outcome. RESULTS: A total of 72 patients [Female = 28 (39%), mean age 55 ± 17.3] with clinical failure and Eckardt score (ES) > 3 who underwent post LHM (33) or POEM (39) were included. On HRM evaluation, 27 were deemed candidates for repeat myotomy based on abnormal integrated relaxation pressure (IRP) measurements >15mmHg. On EndoFLIP evaluation,13/27 had an abnormal distensibility index (DI) < 2.8 mm2/mmHg at 40 ml balloon volume distension (Figure 1). A total of 30 patients underwent conservative management - pneumatic balloon dilation (n = 9) and repeat myotomy (n = 33) (Table 1). Post repeat myotomy mean ES improved from 5.8 ± 2.7 to 1.1 ± 1.4, (P < 0.001), and median DS improved from 2 (IQR: 1-3) to 1 (0-2), (P = 0.03), at a median follow-up time of 2 (IQR: 0-4.5) months post-procedure. Clinical success was achieved in 23/33 (70%) of the patients (Table 2). DI at 40 m balloon distension volume (P = 0.01; odds ratio, 1.51; 95% confidence interval, 1.02-2.1) was identified to be the best independent predictors of clinical success post repeat myotomy, with DI < 3.3 mm2/mmHg having sensitivity and specificity of 64% and 80%, respectively, for predicting clinical success. Therefore, the theoretical impact of EndoFLIP utilization for the management and diagnosis was in 16/72 (22%). CONCLUSION: The findings of this study demonstrate the important role of using EndoFLIP, in addition to HRM, in evaluating patients with clinical failure post myotomy.Figure 1Table 1Table 2

The relationship between biomechanics of pharyngoesophageal segment and tracheoesophageal phonation

This study examined the relationship between biomechanical features of the pharyngoesophageal (PE) segment, acoustic characteristics of tracheoesophageal (TE) phonation, and patients’ satisfaction with TE phonation. Fifteen patients using TE phonation after total laryngectomy completed the Voice Symptom Scale (VoiSS) and underwent acoustic voice analysis for cepstral peak prominence (CPP) and relative intensity. High resolution manometry (HRM) combined with videofluoroscopy was used to evaluate PE segment pressure and calculate the pressure gradient (ΔP), which was the pressure difference between the upper oesophagus and a point two centimetres above the vibrating PE segment. The upper oesophageal sphincter (UOS) minimal diameters were measured by Endolumenal Functional Lumen Imaging Probe (EndoFLIP). HRM detected rapid pressure changes at the level of the 4th – 6th cervical vertebra. CPP, relative intensity, and ΔP were significant predictors of satisfactory TE phonation. ΔP was a significant predictor of CPP and intensity. Minimal UOS diameter was a significant predictor of relative intensity of TE phonation. In two patients with unsuccessful TE phonation, endoscopic dilatation subsequently restored TE phonation. These findings suggest that sufficient ΔP and large UOS diameter are required for satisfactory TE phonation. Endoscopic dilatation increasing UOS diameter may provide a new approach to treat unsuccessful TE phonation.

New Developments in Esophageal Motility Testing

The purpose of this review is to present the latest developments in esophageal motility testing and summarize the current paradigm of esophageal motility disorders. While high-resolution esophageal pressure topography interpreted according to the Chicago Classification represents the gold standard to evaluate esophageal motility, recent studies highlight the additional value of novel manometric applications. Novel applications include provocative measures to assess for obstructive physiology at the esophagogastric junction (EGJ), esophageal peristaltic reserve, and rumination and supragastric belching disorders. Furthermore, high-resolution impedance manometry provides assessment of bolus flow in relation to pressure changes. Distinct from manometry, the endolumenal functional lumen imaging probe examines esophageal motor response to distension to provide complementary and alternative data with regard to EGJ function and esophageal body motor function. Barium esophagram with timed swallow and barium tablet continues to be an important esophageal motility test. Furthermore, current use of multichannel intraluminal impedance-pH monitoring extends beyond reflux monitoring to measure reflux clearance and esophageal epithelial integrity. The diagnostic armamentarium for esophageal motility disorders has expanded tremendously to include a multitude of sophisticated tools. Advancements in diagnostic technology and understanding of esophageal physiology have shifted the field to more precisely characterize esophageal motility and guide phenotype-driven management.

The biomechanical properties of the urethra in boys with hypospadias: a preliminary study

The ventral aspect of the penis in boys with hypospadias is composed of dysplastic tissue of the skin and the urethra. The aim of this study was to assess the pre-operative size and biomechanical properties of urethrae in boys with and without hypospadias using a more objective catheter-based system. In this non-blinded clinical observation study, the study population consisted of 19 boys with hypospadias-the case group (median age 13.9 months [range: 12.2-21.3])-and seven boys without hypospadias-the control group (median age 8.5 months [range: 3.8-18.1]). Modified measurements of impedance were used to assess the size, compliance and viscoelasticity of the urethrae under stepwise increased pressures (between 0, 40 and 60 cmH2O) using a customised Endolumenal Functional Lumen Imaging probe (EndoFLIP®). The sizes of the urethrae in boys with hypospadias are variablebut tendtowards being narrower and less compliant than those of the control subjects i.e. median diameter for meatus urethra was 3.2mm (range: 2.98-3.92) in the hypospadias group compared with 3.64 (range: 3.22-4.44) in the control group at 40 cmH2O, and the median change in diameter at meatus urethra was 0.08mm (range: -0.02 to 0.52) in the hypospadias group compared with 0.23mm (range: -0.02 to 0.34) when the pressure was increased from 40 to 60 cmH2O. This biomechanical analysis found that there was no significant viscoelasticity of the urethral meatus in both the groups, whereas the remainder of the urethral structure generally had viscoelastic properties in the control group, seen as a creep on the time/diameter curves (Figure). In the group of boys with hypospadias, evaluations of the urethrae revealed varying viscoelastic abilities, ranging from abilities that were comparable with those of the control subjectsto no sign of viscoelasticity at all. This study is the first to measure the biomechanical properties of the urethra in children, which might help to provide an understanding as to the structural and functional changes associated with hypospadias. The urethrae in the subjects with hypospadias were variable in diameterbut tended to be narrower overall, especially in the distal portion of the urethra. Furthermore, the urethrae in boys with hypospadias were frequently less viscoelastic than those of controls. The EndoFLIP® system may be a future way of objectively estimating the severity of a urethral obstructionand could potentially be included in the postoperative assessment of patients with signs of hampered voiding.

Emerging Roles of the Endolumenal Functional Lumen Imaging Probe in Gastrointestinal Motility Disorders.

Gastrointestinal sphincters play a vital role in gut function and motility by separating the gut into functional segments. Traditionally, function of sphincters including the esophagogastric junction is studied using endoscopy and manometry. However, due to its dynamic biomechanical properties, data on distensibility and compliance may provide a more accurate representation of the sphincter function. The endolumenal functional lumen imaging probe (EndoFLIP) system uses a multi-detector impedance planimetry system to provide data on tissue distensibility and geometric changes in the sphincter as measured through resistance to volumetric distention with real-time images. With the advent of EndoFLIP studies, esophagogastric junction dysfunction and other disorders of the stomach and bowels may be better evaluated. It may be utilized as a tool in predicting effectiveness of endoscopic and surgical treatments as well as patient outcomes.

Consistency and effect of body position change on measurement of upper and lower esophageal sphincter geometry using impedance planimetry in a canine model.

The EndoFLIP (Endolumenal Functional Lumen Imaging Probe, Crospon Inc, Galway, Ireland) device uses the technique of impedance planimetry to evaluate dimensions and distensibility of the upper and lower esophageal sphincter. The null hypotheses for this study were that EndoFLIP variables would be stable between anesthestic episodes and would not be affected by body position when evaluating the upper and lower esophageal sphincters in healthy dogs. During each of three consecutive general anesthesia episodes administered to eight healthy adult research colony dogs with a standardized protocol, the EndoFLIP catheter was positioned to measure cross-sectional area, intrabag pressure, upper and lower esophageal sphincter length at two different balloon fill volumes (30 and 40 mL) and two body positions (lateral and dorsal recumbency). From these measured variables, a distensibility index was also calculated. Mixed effect analysis of variance was used to evaluate the fixed marginal and interaction effects of anesthesia episode, body position, and balloon volume on measured and calculated variables. For the upper esophageal sphincter significant interactions were present between anesthetic episode and body position for all variables except intrabag pressure; adjusting for body position significant differences were present between anesthetic episodes for all variables except distensibility index; adjusting for anesthetic episode cross-sectional area, intrabag pressure, upper esophageal sphincter length and distensibility index were all affected by body position. For the lower esophageal sphincter distensibility index was the only variable where a significant interaction between anesthesia episode and body position occurred; cross-sectional area, intrabag pressure, and lower esophageal length were not significantly affected by anesthesia episode when adjusting for body position; distensibility index was the only variable significantly affected by body position. Measurements of the geometry of the lower esophageal sphincter as measured by the EndoFLIP device were consistent under conditions of general anesthesia. Similar measurements taken at the upper esophageal sphincter displayed greater variability between anesthetic episodes and were affected to a greater extent by body position. Body position should be standardized in studies using the EndoFLIP to assess geometric and functional characteristics of the upper and lower esophageal sphincters.

Functional Lumen Imaging Probe for the Management of Esophageal Disorders: Expert Review From the Clinical Practice Updates Committee of the AGA Institute.

The functional luminal imaging probe is a Food and Drug Administration-approved measurement tool used to measure simultaneous pressure and diameter to guide management of various upper gastrointestinal disorders. Additionally, this tool is also approved to guide therapy during bariatric procedures and specialized esophageal surgery. Although it has been commercially available since 2009 as the endolumenal functional lumen imaging probe (EndoFLIP), the functional luminal imaging probe has had limited penetrance into clinical settings outside of specialized centers. This is primarily because of a paucity of data supporting its utility in general practice and a lack of standardized protocols and data analysis methodology. However, data are accumulating that are providing guidance regarding emerging applications in the evaluation and management of foregut disorders. This clinical practice update describes the technique and reviews potential indications in achalasia, eosinophilic esophagitis, and gastroesophgeal reflux disease. Best Practice Advice 1: Clinicians should not make a diagnosis or treatment decision based on functional lumen imaging probe (FLIP) assessment alone. Best Practice Advice 2: FLIP assessment is a complementary tool to assess esophagogastric junction opening dynamics and the stiffness of the esophageal wall. Best Practice Advice 3: Utilization should follow distinct protocols and analysis paradigms based on the disease state of interest. Best Practice Advice 4: Clinicians should not utilize FLIP in routine diagnostic assessments of gastroesophageal reflux disease. Best Practice Advice 5: FLIP should not be used to diagnose eosinophilic esophagitis but may have a role in severity assessment and therapeutic monitoring.

Idiopathic Gastroparesis Treated with Gastric Peroral Endoscopic Pyloromyotomy Using Endolumenal Functional Lumen Imaging Probe

Idiopathic Gastroparesis Treated with Gastric Peroral Endoscopic Pyloromyotomy Using Endolumenal Functional Lumen Imaging Probe

Sa1338 Endolumenal Functional Lumen Imaging Probe (EndoFLIP) is an Accurate Intra-Operative Tool That Predicts Short-Term Outcome Following Pneumatic Dilatation (PD) for Idiopathic Achalasia

Sa1338 Endolumenal Functional Lumen Imaging Probe (EndoFLIP) is an Accurate Intra-Operative Tool That Predicts Short-Term Outcome Following Pneumatic Dilatation (PD) for Idiopathic Achalasia

Real-time measurement of luminal compliance during transoral incisionless fundoplication

A 71-year-old woman who had a family history of esophageal cancer presented with symptoms of chronic heartburn. The patient expressed interest in definitive treatment, declining long-term medical therapy and opting to undergo transoral incisionless fundoplication (TIF) ([Fig. 1]). This was accomplished by using the EsophyX Device (EndoGastric Solutions, San Mateo, California, USA). Before and after the TIF procedure, an EndoFLIP Endolumenal Functional Lumen Imaging Probe (Crospon, Carlsbad, California, USA) was used to measure the luminal compliance and high pressure zone of the gastroesophageal junction. EndoFLIP utilizes impedance planimetry technology to measure the geometry and physical properties of hollow lumina. The patient was observed for 24 hours after the procedure and was discharged in a stable condition.

Measurement of esophago‐gastric junction cross‐sectional area and distensibility by an endolumenal functional lumen imaging probe for the diagnosis of gastro‐esophageal reflux disease

Measurement of esophago-gastric junction (EGJ) cross-sectional area (CSA) and distensibility by an Endolumenal Functional Lumen Imaging Probe (EndoFLIP®) may distinguish between gastro-esophageal reflux disease (GERD) patients and healthy volunteers (HV). We aimed to assess the agreement of EndoFLIP® measurements with clinical and physiologic diagnosis of GERD. Twenty-one HV and 18 patients with typical GERD symptoms were studied. After gastroscopy, EGJ CSA, and distensibility were measured by EndoFLIP®. Forty-eight hour esophageal pH monitoring was then performed by a wireless system. The ability of EndoFLIP® to discriminate GERD patient and HVs was assessed. Planned secondary analysis then assessed whether EGJ CSA and distensibility were increased in individuals with pathologic acid exposure. Healthy volunteers were younger and had lower body mass index (BMI; both p < 0.001). Pathologic acid exposure was present in 3/21 (14%) HVs and 9/18 (50%) patients (p = 0.126). At 30 mL EndoFLIP® bag volume, EGJ CSA was higher (p = 0.058) and EGJ distensibility was lower (p = 0.020) in HVs than patients. Secondary analysis showed that EGJ measurements were similar in participants with and without pathologic acid exposure (CSA 98 mm² vs 107 mm²; p = 0.789, distensibility; p = 0.704). An inverse association between BMI and CSA (R² = 0.2758, p = 0.001) and distensibility (R² = 0.2005, p = 0.005) was present. Endolumenal Functional Lumen Imaging Probe is not useful for GERD diagnosis because EGJ CSA and distensibility do not distinguish between HVs and GERD patients defined by clinical presentation or pH measurement. This unexpected result may be due to an important, confounding interaction of obesity.

PTU-178 Measurement of esophago-gastric junction cross-sectional area and distensibility by EndoFLIP® (endolumenal functional lumen imaging probe) for the diagnosis of patients with gastro-esophageal reflux disease (GERD)

IntroductionEndoFLIP® (Crospon, Ireland) is an innovative device designed to assess the cross sectional area (CSA) and distensiblilty of the esophagogastric junction (EGJ) by combined impedance planimetry and pressure measurement. Initial...

Su1076 Measurement of Esophago-Gastric Junction Cross-Sectional Area and Distensibility by Endoflip® (Endolumenal Functional Lumen Imaging Probe) for the Diagnosis of Patients With Gastro-Esophageal Reflux Disease (GERD)

Introduction EndoFLIP ® (Crospon, Ireland) is an innovative device designed to assess the cross sectional area (CSA) and distensiblilty of the esophagogastric junction (EGJ) by combined impedance planimetry and pressure measurement. Initial studies have suggested that this probe may distinguish between gastro-oesophageal reflux disease (GERD) patients and healthy volunteers (HV). Aim To assess the diagnostic agreement of EndoFLIP ® measurements with clinical and physiologic GERD diagnosis. Methods 22 healthy volunteers, (HV; female=16, age 21–46, mean body mass index (BMI) 24.3 kg/m 2 ) and 20 patients with GERD symptoms (female=14, age 19–78, mean BMI 33.2 kg/m 2 ) were studied. Patients were older (p ® balloon volume were measured. A Bravo capsule (Given Imaging, Israel) was attached 6 cm above the Z-line and a 48 h wireless esophageal pH recording acquired. The ability of EndoFLIP ® measurements to discriminate (1) patient group and (2) individuals with pathologic acid exposure (>5.6% time Results Complete measurements were acquired except in one patient with early detachment of Bravo capsule. Distensibility could not be measured in one patient and one volunteer with negative endoFLIP® balloon pressures. 7/22 (32%) HVs and 7/19 (37%) of patients had oesophagitis (six patients with hiatus hernia). 3/22 (14%) HVs and 9/19 (47%) patients had pathologic acid exposure (p=0.126). EGJ CSA was higher in healthy volunteers than the patient group, at 20 ml (p=0.018) and 30 ml (p=0.058, Abstract PTU-178 figure 1) endoFLIP® balloon volume. EGJ distensibility was lower in patients than HVs at 20 ml (p=0.001) and 30 ml balloon volume, (p=0.020, Abstract PTU-178 figure 1). EndoFLIP® measurements were similar in participants with and without pathologic acid exposure (median CSA 40 mm 2 vs 34 mm 2 p=1.0 at 20 ml, 98 mm 2 vs 107 mm 2 , p=0.789 at 30 ml) and distensibility at 20 ml (p=0.574) and 30 ml balloon volume (p=0.704). Post-hoc analysis revealed an inverse association between BMI and CSA (R 2 =0.214, p=0.003) and negative association with distensibility (R 2 =0.211, p=0.003). BMI was associated also with a trend to increased acid exposure (p=0.116). Conclusion EndoFLIP® is not useful for GERD diagnosis as EGJ CSA and distensibilty do not distinguish between HVs and GERD patients defined by clinical presentation or pH measurement. This unexpected result may be due to an important interaction of obesity with EndoFLIP® measurements. Competing interests None declared.