High-resolution Impedance Manometry Research Articles

Esophago-gastric junction findings on high resolution impedance manometry in children with esophageal atresia.

Using high resolution impedance manometry (HRIM), this study characterized the esophago-gastric junction (EGJ) dynamics in children with esophageal atresia (EA). Esophageal HRIM was performed in patients with EA aged less than 18 years. Objective motility patterns were analyzed, and EGJ data reported. Controls were pediatric patients without EA undergoing investigations for consideration of fundoplication surgery. Seventy-five patients (M:F = 43:32, median age 1 year 3 months [3 months-17 years 4 months]) completed 133 HRIM studies. The majority (64/75, 85.3%) had EA with distal tracheo-esophageal fistula. Compared with controls, liquid swallows were poorer in patients with EA, as evident by significant differences in distension pressure emptying and bolus flow time (BFT). The integrated relaxation pressure for thin liquid swallows was significantly different between EA types, as well as when comparing patients with EA with and without previous esophageal dilatations. The BFT for solid swallows was significantly different when compared with EA types. We have utilized HRIM in patients with EA to demonstrate abnormalities in their long-term EGJ function. These abnormalities correlate with poorer esophageal compliance and reduced esophageal peristalsis across the EGJ. Understanding the EGJ function in patients with EA will allow us to tailor long-term management to specific patients.

The impact of lung transplantation on esophageal motility and inter-relationships with reflux and lung mechanics in patients with restrictive and obstructive respiratory disease.

For many patients with lung disease the only proven intervention to improve survival and quality of life is lung transplantation (LTx). Esophageal dysmotility and gastroesophageal reflux (GER) are common in patients with respiratory disease, and often associate with worse prognosis following LTx. Which, if any patients, should be excluded from LTx based on esophageal concerns remains unclear. Our aim was to understand the effect of LTx on esophageal motility diagnosis and examine how this and the other physiological and mechanical factors relate to GER and clearance of boluses swallowed. We prospectively recruited 62 patients with restrictive (RLD) and obstructive (OLD) lung disease (aged 33-75 years; 42 men) who underwent high resolution impedance manometry and 24-h pH-impedance before and after LTx. RLD patients with normal motility were more likely to remain normal (p = 0.02), or if having abnormal motility to change to normal (p = 0.07) post-LTx than OLD patients. Esophageal length (EL) was greater in OLD than RLD patients' pre-LTx (p < 0.001), reducing only in OLD patients' post-LTx (p = 0.02). Reduced EL post-LTx associated with greater contractile reserve (r = 0.735; p = 0.01) and increased likelihood of motility normalization (p = 0.10). Clearance of reflux improved (p = 0.01) and associated with increased mean nocturnal baseline impedance (p < 0.001) in RLD but not OLD. Peristaltic breaks and thoraco-abdominal pressure gradient impact both esophageal clearance of reflux and boluses swallowed (p < 0.05). RLD patients are more likely to show improvement in esophageal motility than OLD patients post-LTx. However, the effect on GER is more difficult to predict and requires other GI, anatomical and pulmonary factors to be taken into consideration.

Pediatric retrograde cricopharyngeal dysfunction diagnosed by high-resolutionimpedance manometry.

The inability to burp, known as retrograde cricopharyngeal dysfunction (R-CPD), was initially described in adults. The proposed clinical diagnostic criteria for R-CPD include belching inability, abdominal bloating and discomfort/nausea, postprandial chest pain, and involuntary noises. Botulinum toxin injection to the cricopharyngeal muscle has been reported to be beneficial. High-resolution esophageal impedance-manometry (HRIM) features in adolescent patients with R-CPD have not been described yet. The aim of our study was to describe the clinical and HRIM findings of pediatric patients with R-CPD. Clinical and manometric features of five pediatric patients diagnosed with R-CPD were reviewed. HRIM study protocol was modified to include the consumption of carbonated drink to provoke symptoms and distinctive manometric features. We report five female patients aged 15-20 years who presented with an inability to burp and involuntary throat sounds. HRIM revealed normal upper esophageal sphincter (UES) relaxation during swallowing, but abnormal UES relaxation with concurrent high esophageal impedance reflecting air entrapment and secondary peristalsis following the carbonated drink challenge. Four patients exhibited esophageal motility disorder. All patients reported improvement or resolution of symptoms after botulinum toxin injection to the cricopharyngeus muscle. Adolescents with an inability to burp, reflux-like symptoms, bloating, and involuntary throat noises should be assessed for R-CPD by pediatric gastroenterologists with HRIM. The relatively recent recognition of this novel condition is the likely reason for its under- and misdiagnosis in children.

The role of high-resolution impedance manometry to identify rumination syndrome in children with unexplained foregut symptoms.

Diagnosis of rumination syndrome (RS) relies on Rome IV criteria. Oesophageal high-resolution impedance manometry (HRIM) can objectively demonstrate the episodes of rumination, but its role in the diagnostic pathway is not yet established. We aimed to demonstrate the clinical contribution of this tool for the timely diagnosis of RS and diagnostic work-up of children with unexplained foregut symptoms deemed to be due to other conditions. HRIMs performed between 2012 and 2021 were searched to retrieve all diagnoses of RS. Medical records were reviewed for clinical data. Out of 461 HRIMs performed, 76 children had manometric diagnosis of RS (35 male, median age: 13 years). Of them, 47% were not clinically suspected as the symptoms did not fulfil clinical criteria for RS. The indications for HRIM in these cases were investigation of unexplained foregut symptoms (37%), suspected refractory gastroesophageal reflux disease (8%) and dysphagia (2%). Among all HRIMs performed for investigations of unexplained foregut symptoms (n = 80), 35% demonstrated rumination episodes. Identification of characteristic patterns of rumination on HRIM in children with unexplained foregut symptoms enables the immediate diagnosis of RS. Thus, in situations of diagnostic uncertainty, the use of HRIM at early stages of the diagnostic pathway would reduce unnecessary investigations and treatments.

Intraoesophageal pressure in patients receiving proximal gastrectomy with hinged double flap method for gastric cancer: a retrospective cohort study

Background: Objective functional assessment of esophagogastric anastomosis in patients who underwent proximal gastrectomy with the hinged double flap method for gastric cancer has not been well investigated. This study aimed to perform a functional analysis of reconstruction using high-resolution impedance manometry (HRIM). Materials and methods: The authors enroled 25 patients who underwent proximal gastrectomy for gastric cancer between May 2015 and April 2020 and subsequently underwent HRIM postoperatively. Eligible questionnaires [Postgastrectomy Syndrome Assessment Scale-37 (PGSAS-37)] were retrieved from 16 patients. The association between HRIM data and PGSAS-37 was analyzed. Results: The amplitudes of distal oesophageal peristaltic waves, contractile front velocity, and distal latency assessed by HRIM were almost normal after surgery. Most patient’s lower oesophageal sphincter (LES) resting pressure created by the hinged double flap was within normal limits. Conversely, LES residual pressure values during swallowing-induced relaxation were abnormally high in most patients, and the lower the values, the more severe the reflux and diarrhoea symptoms (P=0.038, P=0.041, respectively). In addition, even when the integrated relaxation pressure (IRP) was normal, lower values corresponded to more severe reflux symptoms (P=0.020). The required LES pressure may be higher after proximal gastrectomy because of the relatively higher intragastric pressure due to the reduced volume of the remnant stomach. This also suggests that swallowing-induced relaxation of the LES was considered a trigger for oesophageal reflux in post-proximal gastrectomy patients. Conclusion: LES residual pressure and IRP values in HRIM correlated with reflux symptoms in patients after proximal gastrectomy.

Interpretation of Impedance Data on High-resolution Impedance Manometry Studies-A Worldwide Survey.

Esophageal manometry is the gold standard for esophageal motility evaluation. High-resolution esophageal manometry with impedance (HRIM) allows concurrent assessment of bolus transit and manometry. Inconsistencies between concomitant impedance and manometry data pose a clinical dilemma and has not yet been addressed. We aim to assess interpretation trends of HRIM data among gastroenterologists worldwide. A cross-sectional study using an anonymous survey was conducted among gastroenterologists worldwide. Statistical analysis was performed to compare responses between providers. We received responses from 107 gastroenterologists (26 countries). Most were adult providers (69, 64.5%), and most (77, 72.0%) had > 5 years of experience. Impedance was found to be helpful by 83 (77.6%) participants, but over 30% reported inconsistencies between impedance and manometry data. With incomplete bolus clearance and normal manometry 41 (38.7%) recommended observation, 41 (38.7%) recommended 24-hours pH-impedance, and 16 (15.1%) recommended prokinetics. With abnormal manometry and complete bolus clearance, 60 (57.1%) recommended observation while 18 (17.1%) recommended 24-hours pH impedance and 15 (14.3%) recommended prokinetics. A significant difference was found between providers from different continents in treating cases with discrepancy between impedance and manometry findings (P < 0.001). No significant differences were seen in responses between adult versus pediatric providers and between providers with different years of experience. There is no consensus on interpreting HRIM data. Providers' approaches to studies with inconsistencies between manometry and impedance data vary. There is an unmet need for guidelines on interpreting impedance data in HRIM studies.

Investigating Parkinson's disease with dual high resolution pharyngeal manometry with impedance and videofluoroscopy.

To characterize pharyngeal function in people with Parkinson's Disease using both high resolution impedance manometry (HRIM) and videofluoroscopy (VFSS) and to explore correlations between VFSS and HRIM metrics. All participants received both VFSS and HRIM within 24 h-time window. A standard VFSS protocol (IDDSI 0: 1 mL, 3 mL, 20 mL, and 100 mL) was performed. A solid-state unidirectional catheter (36 pressure sensors) was used to acquire manometric data for triplicate swallows (IDDSI 0: 5 mL, 10 mL, 20 mL), quantitative swallow analysis was completed through Swallowtail™ and SwallowGateway™. Parameters were compared to published norms and statistical tests explored correlational associations (p < 0.05). Twenty-one participants (76% male; mean age 70 years, SD7.16) with mild-moderate severity PD were recruited with 73% reporting Eating Assessment Tool (EAT-10) scores ≥3 indicating swallow impairment. Compared to normal metrics, one third of participants had abnormally elevated hypopharyngeal contractile integral (HPCI), hypopharyngeal peak pressure, upper esophageal sphincter (UES) integrated relaxation pressure (UES IRP), and reduced UES maximum admittance. Five participants showed compromised swallow safety (Penetration-Aspiration Scale score ≥6). One third of participants had abnormal VFSS values for pharyngoesophageal segment (PES) opening duration, maximum PES opening distance, and maximum hyoid displacement measures. Some HRIM metrics had a strong correlation with pharyngeal VFSS measures (r > 0.60, p < 0.05). This study identifies early manometric signs of pharyngeal dysfunction in people with PD. The congruence of the VFSS and HRIM measures confirms the hypothesis of insidious early decline in swallow function in PD despite maintenance of airway safety (i.e., low aspiration rates).

When symptoms are more than reflux.

45 year-old male patient with history of heartburn and regurgitation of non-acid food in the immediate postprandial period, with no symptomatic improvement after anti-acid treatment. The patient underwent an upper endoscopy that was unremarkable. A high-resolution impedance manometry (HRIM) was performed according to Chicago Protocol 4.0, as well as an additional solid test meal, with findings of rumination syndrome (RS) (figure 1). The study was completed with a 24-hour impedance pH monitoring that showed, in the immediate postprandial period, episodes of reflux that reached the proximal sensor followed by a normal swallow (figure 2). Abdominophrenic biofeedback was started with clinical improvement and anti-acid treatment was maintained at once a day. Discussion: RS is diagnosed by a complete clinical history, using the Rome IV or DSM-5 criteria (figure 3). Due to lack of knowledge of the disease and the fact that regurgitation can be present in other conditions including gastroesophageal reflux disease and achalasia, most patients undergo multiple tests and visit several physicians before reaching the diagnosis1. The gold standard investigation for RS, in cases where there are diagnostic doubts, is HRIM with solid meal administration, that shows a sudden increase in intragastric pressure > 30 mmHg concurrent with a drop in impedance and both simultaneous lower and upper esophageal sphincter relaxation, that may or may not be followed by re-swallowing food2. Rumination episodes can appear spontaneously (type 1) or may be preceded by a reflux episode (type 2) or a supragastric belch (type 3)3. 24-hour impedance pH monitoring cannot confirm de diagnosis, but during rumination, in the majority of episodes, the refluxed material reaches the proximal esophagus2.

Characteristics of Esophageal Motility and Associated Symptom Profiles in Patients with Esophageal Diverticulum: A Study Based on High-Resolution Impedance Manometry.

Esophageal diverticulum (ED) is an uncommon structural disorder with heterogenous manifestations and elusive pathophysiology. Our aim was to investigate esophageal motility and associated symptom profiles in patients with ED based on high-resolution impedance manometry (HRIM). Consecutive patients with ED referred to our motility laboratory between 2015 to 2022 were identified in our electronic database. All patients were evaluated based on an upper endoscopy, HRIM, and standardized symptom questionnaires. Patients with ED were further stratified into upper, middle, and lower (epiphrenic) cases. Esophageal motility was evaluated with HRIM and the updated Chicago Classification v4.0. Twenty-four patients with ED (9 upper, 4 middle, and 11 epiphrenic) were analyzed. Patients with ED were generally older (mean: 65 ± 13.3years) and predominantly women (58.3%). Most ED cases were unilaterally located (95.8%) and left-side predominant (62.5%). Mean symptom duration was 20months (range: 1-120) and the most common symptoms were dysphagia (70.8%) and regurgitation (37.5%). Erosive esophagitis was noted in 16 patients (69.6%), while barium stasis was noted in 5 patients (20.8%). Fourteen patients (58.3%) were diagnosed with esophageal motility disorders using HRIM, with achalasia being the most common diagnosis (n = 5, 20.8%). Patients with epiphrenic diverticulum had significantly higher symptom scores and achalasia prevalence. Patients with ED tended to be older and was associated with a high prevalence of EMD. A multi-disciplinary evaluation, including complete anatomical and motility surveys, may help clarify the underlying pathophysiology and tailor further treatment strategies.

Higher obesity class is associated with more severe esophageal symptoms and reflux burden but not altered motor function or contractile reserve.

Patients with obesity often report esophageal symptoms, with abnormal reflux and esophageal motility suggested as potential mechanisms. However, prior studies showed varying results, often limited by study design/size and esophageal function/symptom measures utilized. We aimed to examine the relationship between obesity and objective esophageal function testing and patient-reported outcomes, utilizing prospective symptom, manometric and reflux monitoring data with impedance. Adults referred for high-resolution impedance-manometry (HRiM) and multichannel intraluminal impedance-pH monitoring (MII-pH) to evaluate esophageal symptoms were enrolled. Validated symptom and health-related quality of life (HR-QOL) instruments were prospectively collected: GERDQ, reflux symptoms index (RSI), dominant symptom intensity (DSI, multiplied 5-point Likert scales for symptom frequency/severity), global symptom severity (GSS, 100-point visual analog scale), and Short Form-12 (SF-12) for HR-QOL. Esophageal function testing measures were compared across body mass index (BMI) categories and correlated with patient-reported outcomes. Seven hundred and fifty four patients were included (Normal:281/Overweight:253/Class I obesity:137/Class II/III obesity:83). Reflux burden measures on MII-pH (acid exposure time, total reflux episodes, bolus exposure time), conclusive pathologic reflux (Lyon), and hiatal hernia were increased in higher obesity classes compared to normal BMI. Class II/III obesity was associated with more normal/hypercontractile swallows, less ineffective swallows, and better bolus transit on HRiM. BMI correlated positively with GERDQ/RSI/DSI/GSS, and negatively with physical component score (SF-12). Esophageal symptom severity and HR-QOL correlated strongly with MII-pH findings, but not HRiM measures. Obesity is associated with increased esophageal symptom burden and worse physical HR-QOL, which correlate with higher acid/bolus reflux burden but not altered esophageal motility/transit/contractile reserve.

Effect of peroral endoscopic myotomy on growth and esophageal motility for pediatric esophageal achalasia

Peroral endoscopic myotomy (POEM), a novel minimally invasive treatment for esophageal achalasia, has been shown to be effective and safe for both adult and pediatric patients. However, studies on its application in children in Taiwan and its impact on growth and esophageal motility are lacking. We conducted a retrospective study on consecutive pediatric patients who were diagnosed with esophageal achalasia at National Taiwan University Hospital and underwent POEM during 2015-2022. Disease characteristics and treatment outcomes were analyzed. Ten patients (age 16.9±3.1 years), nine newly diagnosed and one previously treated with pneumatic dilatation, underwent POEM for achalasia (type I/II/III: 3/7/0). Average symptom duration before diagnosis was 19.4±19.9 months, mean POEM procedure time was 83.6±30.7min, and clinical success (Eckardt score ≤3) was achieved in all patients. Eight patients experienced mild adverse events during POEM, but none required further endoscopic or surgical intervention. Over a mean follow-up period of 3.7±1.6 years, mean Eckardt score decreased significantly from 5.7±2.4 to 1.1±0.7 (p=0.0001). The BMI z-score also increased significantly after POEM (p=0.023). Five patients received follow-up high-resolution impedance manometry (HRIM), and all had improved lower esophageal sphincter resting pressures (p=0.011), body contractility, and bolus transit (p=0.019). POEM is an effective and safe treatment for pediatric achalasia in Taiwan. Early diagnosis and treatment with POEM may help to restore esophageal function and nutrition status in children.

Characterising oesophageal motility disorders by high-resolution impedance manometry in dermatomyositis patients.

We studied high-resolution impedance manometry (HRiM) findings in dermatomyositis (DM) to detect oesophageal dysmotility, even in asymptomatic patients, and correlated the alterations to clinical and serological disease domains. We performed a cross-sectional study of DM patients, enrolled between December 2021 and December 2022. All patients underwent rheumatological, laboratory and HRiM assessment. HRiM findings were compared with different clinical and serological profiles. The study population consisted of 15 DM patients (13 women and 2 men, age 54±15.2 years). The mean disease duration was 6.6 years. According to HRiM findings, three different groups of oesophageal disease severity were identified (in order of severity G0, G1 and G>1, 5 patients per group). G>1 group was significantly associated with MDA5 antibodies (80% vs. 20%, p<0.05). Interstitial lung disease (ILD) did not show any significant association with HRiM findings. However, a diffusing lung capacity for carbon oxide (DLCO) < 80% was present in 100% of G>1 (p<0.05). No associations between dysphagia, creatine kinase (CK) level, muscle weakness, skin, articular involvement and treatment were found. Oesophageal involvement is frequent and should be evaluated in the comprehensive work-up of DM. We used for the first time HRiM in DM, which proved to be an accurate and objective technique in assessing oesophageal disease, even in the subclinical stage. Interestingly, the MDA5-positive group had a higher burden of HRiM pathological findings, suggesting a greater severity of oesophageal involvement, often asymptomatic.

Elucidation of gastric motor function caused by gastroesophageal reflux in Rumination syndrome

Rumination syndrome (RS) is a disease of the gastrointestinal (GI) tract characterised by repeated regurgitation of recently digested food back into the mouth. It can be difficult to distinguish from gastro-oesophageal reflux disease (GERD) and it is likely that many RS patients are treated for GERD due to being misdiagnosed. Assistant Professor Kenichiro Nakagawa is leading a team of experts based in the Division of Gastroenterology, Tohoku University Graduate School of Medicine, Japan, investigating the causes of gastroesophageal reflux. The researchers have already found that RS and GERD are very different in terms of pathology. They are using high-resolution impedance manometry (HRIM) as a diagnostic tool to comprehensively assess the motor function and bolus transit of food through the oesophagus. They are also utilising oesophageal multichannel intraluminal impedance-pH (MII-pH) monitoring to assess the pH of targeted oesophageal and gastric regions of the GI tract. In doing so, the team can pinpoint gastroesophageal reflux patterns, in turn highlighting the differences in gastroesophageal reflux patterns between RS and GERD patients and healthy control subjects. Using oesophagogastric scintigraphy, the researchers can compare the ratio of regurgitated food during gastroesophageal reflux in their three test groups, analysing where the food residue in RS and GERD patients and healthy control subjects localises in the proximal stomach.

Correlation of Esophageal Mean Nocturnal Baseline Impedance With Markers of Laryngopharyngeal Reflux.

Mean nocturnal baseline impedance (MNBI) is a measure of the esophageal epithelial barrier function calculated via high-resolution impedance manometry and can be used as a diagnostic tool and treatment response predictor for gastroesophageal reflux disease (GERD). However, its utility for laryngopharyngeal reflux (LPR) has been minimally studied. We aimed to investigate the relationship of MNBI between patients with suspected LPR, healthy controls, and their 24-h multichannel intraluminal impedance-pH (MII-pH) study results. Retrospective patient series analysis was performed of patients with suspected LPR and healthy controls who underwent 24-h MII-pH monitoring. MNBI values were calculated from impedance channels at the level of the hypopharynx, proximal esophagus, and distal esophagus. We compared these MNBI values between the subject groups with secondary analysis on MII-pH results, reflux symptom index, reflux findings score, DeMeester score, and salivary pepsin levels. Twenty-three patients with suspected LPR and 14 healthy controls were enrolled. Decreased distal esophageal MNBI was found to be significantly decreased in patients with suspected LPR compared with healthy controls (p< 0.01) and in subjects with positive MII-pH studies compared to negative MII-pH studies (p< 0.01). There were no significant correlations of MNBI at the hypopharynx or proximal esophagus. Distal esophageal MNBI has significant correlations with many phenotypic and biological markers of LPR. These findings indicate that MNBI has the potential to be applied to LPR, similar to its emerging use as a diagnostic tool and treatment response predictor for GERD. 3 Laryngoscope, 133:1927-1932, 2023.

S496 A Comparison of Manometric and Functional Lumen Impedance Planimetry (FLIP) Diagnoses of Esophageal Dysmotility

Introduction: Functional lumen impedance planimetry (FLIP) has been utilized extensively as an adjunct to high resolution impedance manometry (HRIM) for evaluating disorders of esophageal dysfunction. HRIM and FLIP provide valuable metrics that provide similar but distinct information about esophageal function, resulting in similar but distinct diagnoses. For both tools to be used in parallel to diagnose esophageal disorders, it is imperative to understand concordance rate of diagnoses between the two studies.The aim of this study is to evaluate the extent of agreement between FLIP and HRIM diagnoses by constructing parallels between diagnoses made by FLIP and HRIM on patients who underwent both studies and evaluating whether the modalities aligned by more than random chance. Methods: A retrospective review of 227 patient charts was performed. Pairs of similar HRIM and FLIP diagnoses pertaining to peristaltic and aperistaltic conditions were formed by comparing and correlating the criteria for each diagnosis by HRIM to criteria by FLIP. Diagnoses without a correlation were designated “other.” The number of patients whose FLIP and HRIM diagnoses were and were not in agreement was recorded for each diagnosis pair. Results: Table shows the specific HRIM and FLIP diagnoses that were correlated, the number of the patients in which their diagnoses by HRIM and FLIP represent the same condition, and the percentage of the patients with each HRIM diagnosis that had the predicted correlating FLIP diagnosis.The overall percentage in agreement among all diagnoses was 26%. Cohen’s Kappa of agreement for all studies was statistically significant at 0.121 (p < 0.0001). When “other” diagnoses without matching diagnoses between HRIM and FLIP were omitted from analysis, agreement increased to 33.5%. Cohen’s Kappa of agreement for paired diagnoses was statistically significant at 0.157 (p < 0.0001). Conclusion: Our study found that FLIP testing agreed with manometric diagnosis more often than random chance would predict, but only 26% of the time. The studies are therefore slightly predictive of one another, though imperfectly. The tools analyze different aspects of esophageal physiology to arrive at their diagnoses. This both complicates direct pairing of diagnoses and also provides each modality a unique role in assessing esophageal dysmotility. These findings support that HRIM and FLIP testing may be considered complementary tools to utilize in parallel for patients with suspected esophageal dysmotility. Table 1. - Correlated HRIM (High Resolution Impedance Manometry) and FLIP (Functional Lumen Impedance Planimetry) Diagnoses and Their Agreement Rates HRIM Diagnosis Correlating FLIP Diagnosis Number in Agreement Percent of Total in Agreement Normal Normal 7 41.2% Diffuse Esophageal Spasm Normal Distensibility with Repetitive Retrograde Contractile Response 0 Undefined Type 1 Achalasia EGJOO with Absent Contractile Response 14 77.8% Type 3 Achalasia EGJOO with Repetitive Retrograde Contractile Response 5 33.3% EGJOO EGJOO with Normal Contractile Response 29 25.7% Aperistalsis Normal Distensibility with Absent Contractile Response 2 33.3% Other (Jack Hammer, Ineffective Esophageal Motility, Type 2 Achalasia, Fragmented Peristalsis) Other (Normal Contractile Response with Increased EGJ Distensibility, Absent Contractile Response with Increased EGJ Distensibility, Diminished or Disordered Contractile Response) 1 1.9% EGJ - Esophagogastrojejunal, EGJOO - Esophagogastrojejunal Outflow Obstruction)

S484 Characterizing Lower Esophageal Sphincter Dysfunction, Integrated Relaxation Pressure vs Distensibility Index: Who Gives a Flip?

Introduction: Characterizing lower esophageal sphincter dysfunction is of paramount importance when classifying disorders of esophageal motility. Integrated relaxation pressure (IRP) during high resolution impedance manometry (HRIM) has traditionally been used but has been found to be imperfect. Functional lumen impedance planimetry (FLIP) has been developed to be complementary with HRIM for discerning esophageal motility disorders. The aim of this study is to evaluate the relationship between distensibility index (DI) and IRP pertaining to LES relaxation made with FLIP compared with HRIM. Methods: A retrospective review of 227 patients was performed. Patients were classified as having normal IRP (less than 15 mmHg) or abnormal IRP (greater than or equal to 15 mmHg) as measured by HRIM. The average distensibility index as measured by FLIP for patients in both groups was compared. The patient groups were then subdivided into four groups on the basis of normal or abnormal DI using each of the common standards for abnormality (less than or equal to 2.8 mm2/mmHg and less than or equal to 2.0 mm2/mmHg). Fisher’s exact analysis was completed to determine whether abnormal IRP and abnormal DI are related. Results: In patients with a normal IRP (< 15) as measured by HRIM, the mean DI was 4.02 with a standard deviation of 2.89. In patients with abnormal IRP ( ≥ 15), the mean DI was 3.03 with a standard deviation of 2.58. The difference in the mean DIs was statistically significant (p-value = 0.0234, t-test) . Table illustrates the number of patients in each IRP and DI subgroup using both cutoff standards. There was no statistically significant difference in the observed patient frequencies of any classification than would be expected by chance. Conclusion: We found that a normal IRP (< 15mmHg) is associated with higher DIs and that an abnormal IRP (≥15 mmHg) was associated with a DI ≤ 3.1. However, abnormal DI by the standards of either cutoff was not related to having abnormal IRP. Our data supports that both a high IRP and reduced DI suggest impaired LES relaxation, but a DI of less than 2.0 and 2.8 does not predict an IRP of less than 15 mmHg, suggesting some variability between the two metrics. While the chi-squared analysis approached but did not achieve statistical significance in this study, repetition with larger sample sizes in the future may yield a clearer relationship between abnormal IRP and abnormal DI. Table 1. - Fisher's Exact Test of Number of Patients Classified By Distensbility Index (DI) and Integrated Relaxation Pressure Normality and Abnormality DI < 2.8 mm2/mmHg DI ≥ 2.8 mm2/mmHg DI < 2.0 mm2/mmHg DI ≥ 2.0 mm2/mmHg IRP< 15 mmHg 16 32 11 37 IRP ≥15 mmHg 81 83 63 101 p = 0.07 p = 0.06

High-resolution impedance manometry for comparing bolus transit between patients with non-obstructive dysphagia and asymptomatic controls.

Currently, there are no high-resolution impedance manometry (HRIM)-based diagnostic criteria for non-obstructive dysphagia (NOD). New impedance parameters, such as the esophageal impedance integral (EII) and volume of inverted impedance (VII) ratios, have shown strong correlations with bolus transit. This study compared the EII and VII ratios as diagnostic tools for NOD. We analyzed 36 participants (12 patients with achalasia, 12 patients with NOD [7 with normal motility and 5 with ineffective esophageal motility], and 12 asymptomatic controls) who underwent HRIM with a maximum of 5 swallows per participant. The EII and VII ratios were calculated as Z2 (post-swallow)/Z1 (pre-swallow). Bolus transit was retrospectively evaluated using transluminal impedance analysis. Both EII and VII ratios could effectively distinguish the achalasia group from the non-achalasia groups (area under the receiver operating characteristic curve [AUROC]: 0.83 for VII vs. 0.80 for EII; p=0.73). However, the VII ratio was significantly better in discriminating asymptomatic controls from patients with dysphagia (NOD + achalasia) (AUROC: 0.81 vs. 0.68; p=0.01). Moreover, the VII ratio was better in discriminating asymptomatic controls from patients with NOD (AUROC: 0.68 vs. 0.51; p=0.06). In repeated swallows, the VII ratio was consistently the lowest in controls and the highest in patients with achalasia, whereas the EII ratio did not show a consistent pattern. The VII ratio was more reliable than the EII ratio for describing bolus transit and distinguishing patients with NOD from asymptomatic controls, even during repeated measures of subsequent swallows.

Clinical Characteristics and Associated Psychosocial Dysfunction in Patients With Functional Dysphagia: A Study Based on High-Resolution Impedance Manometry and Rome IV Criteria.

The pathophysiology of functional dysphagia as defined by the updated Rome IV criteria is complex and remains largely unknown. We aimed to investigate its clinical characteristics and its association with psychosocial comorbidities. Consecutive patients referred to our motility laboratory for evaluation of esophageal dysphagia were identified. All patients were assessed with upper endoscopy, high-resolution impedance manometry, and validated symptom questionnaires. Data from those who were diagnosed with functional dysphagia (n = 96) based on the Rome IV criteria were analyzed. Age- and sex-adjusted healthy volunteers were also enrolled for comparison. Psychiatric comorbidity and poor sleep quality were defined as total score of 5-item Brief Symptom Rating Scale ≥6 and Pittsburgh Sleep Quality Index ≥6, respectively. The age peak of patients with functional dysphagia was at 40-60 years (47.9%) with females predominant (67%). Forty-four patients (45.8%) had psychiatric comorbidities, whereas 80 (83.3%) experienced poor sleep quality. Female patients were more likely to have trouble falling asleep, shorter sleep duration, and severe bloating. Compared with the healthy volunteers, patients with functional dysphagia had higher 5-item Brief Symptom Rating Scale and Pittsburgh Sleep Quality Index scores (5.34 ± 3.91 vs 1.84 ± 2.61, 9.64 ± 4.13 vs 4.77 ± 3.60, both P < 0.001) but similar results on high-resolution impedance manometry. Those with ineffective esophageal motility (16.7%) had less sleep efficiency than those with normal motility. Patients with functional dysphagia were mainly middle-aged women and had a high prevalence of psychiatric comorbidities and sleep disturbances, especially in female patients. Patients with functional dysphagia displayed similar esophageal motility as the healthy volunteers did.

Normative values of intra-bolus pressure and esophageal compliance based on 4D high-resolution impedance manometry.

This study aimed to quantify normative values of phase-specific intra-bolus pressure (IBP) and esophageal distensibility using 4D analysis of high-resolution-impedance manometry (HRIM). HRIM studies of supine swallows from 34 normal controls were analyzed with respect to the four phases of bolus transit: (1) accommodation, (2) compartmentalization, (3) peristalsis/esophageal emptying, and (4) ampullary emptying. Phase-specific IBP, bolus volume, and distensibility index (DI) in the esophageal body and esophagogastric junction (EGJ) during phases 1-3 were extracted. The median (5-95th/IQR) IBP values were as follows: phase 1: 4.0 (-2.0-10.4/1.9-5.8)mmHg, phase 2: 5.7 (0.2-14.1/3.6-8.9)mmHg, and phase 3: 11.2 (2.9-19.4/7.7-15.1)mmHg. The median bolus volume calculated by integrating impedance planimetry cross-sectional areas was 4.1ml during the compartmentalization phase. The EGJ-DI at max EGJ diameter during phase 2 and 3 was 2.8 (1.1-9.5/1.8-3.7)mm2 /mmHg and 6.0 (3.2-20.3/5.1-7.8)mm2 /mmHg, respectively. The phase 3 EGJ-DI values (6.0 (3.2-20.3/5.1-7.8)mm2 /mmHg) were similar to those calculated using functional lumen imaging probe (FLIP) at the 60 ml volume on the same subjects (5.8 [3.5-7.2/5.0-6.4]mm2 /mmHg). 4D-HRIM provides a standardized methodology to track the nadir impedance and provide measurements of IBP during maximal distention across phases 1-3 of bolus transit. Median IBP and delta IBP were different across the phases, supporting the need to define IBP by phase. Additionally, the EGJ-DI calculated during phase 3 was similar to the 60-ml EGJ-DI from FLIP in the same subjects suggesting that 4D-HRIM can quantify EGJ opening during primary peristalsis.

Impact of Surgical Intervention on Nonobstructive Dysphagia: A Retrospective Study Based on High-Resolution Impedance Manometry in a Taiwanese Population at a Single Institution.

Esophageal motility disorders account for a large proportion of nonobstructive dysphagia cases, which constitute a heterogeneous group of diagnoses that commonly result in peristaltic derangement and impaired relaxation of the lower esophageal sphincter. We performed a single-institution retrospective study enrolling consecutive patients with chief complaints of dysphagia who underwent HRIM from December 2014 to December 2019, and analyzed demographic, clinical, and manometric data using descriptive statistics. In total, 277 identified patients were included in the final analysis. Ineffective esophageal motility (n = 152, 24.5%) was the most common diagnosis by HRIM, followed by absent contractility, EGJ outflow obstruction, type II achalasia, and type I achalasia. Furthermore, surgery including exploratory, laparoscopic, and robotic myotomy, as well as POEM, is considered the most effective treatment for patients with non-spastic achalasia and EGJOO, due to its effective symptom palliation and prevention of disease progression; surgery also contributes to an obvious improvement of dysphagia compared with slightly less efficacy for other related symptoms. Our study aimed to elaborate the clinical characteristics of patients with nonobstructive dysphagia based on HRIM in a Taiwanese population, and to analyze the therapeutic outcomes of such patients who ultimately underwent surgical interventions.