Introduction

Oesophageal high-resolution manometry (HRM) is the test of choice for the study of oesophageal motility disorders. The Chicago 4.0 classification facilitates analysis and interpretation of these studies. However, the influence of patient position and analysis methodology of some parameters is not well defined. In addition, it has not been precisely defined where to place the gastric pressure sensor to determine the integrated relaxation pressure (IRP).

Aims & Methods

The aim was to evaluate if postural changes and analysis methodology applied affect the results of oesophageal high-resolution manometry.
Oesophageal HRM with Chicago 4.0 extended protocol (10 swallows in supine and 10 swallows in up-right position) performed in our Neurogastroenterology and Motility Unit between December 2021 and October 2022 were included. The distal contraction integral (DCI) was determined automatically and manually. The IRP was evaluated positioning the gastric pressure sensor in the lowest gastric area pressure zone (GS-LP) and 2 cm below the lower oesophageal sphincter (GS-2cm).

Results

A total of 96 patients were included, 65% women (mean age 57 years). Mains indications of oesophageal HRM were GERD symptoms (52%) and dysphagia (41%). DCI values were significantly higher in the supine position (2607 and 2014 mmHg/cm/sec with automatic and manual analysis respectively, p<0,0001) compared to the up-right position (1558 and 1371 mmHg/cm/sec with automatic and manual analysis respectively, p<0,0001). These represent changes in the diagnosis of 11% of the studies regarding methodology and 17% regarding posture. A higher proportion of ineffective peristalsis was observed with manual analysis in the up-right position. Additionally, IRP values were significantly higher in both positions using GS-LP (15.5 and 11.1 mmHg) rather than GS-2cm (11.9 and 7.9 mmHg). This represents an increase in the proportion of oesophageal outflow obstruction using GS-LP in both positions.

Conclusion

The position and analysis methodology applied affects the distal contractile integral values. The location of the gastric reference sensor affects the integrated relaxation pressure value. Manometric diagnosis can change depending on the selected posture and analysis methodology applied. Consensus on posture and analysis methodology for oesophageal high-resolution manometry is needed to reduce differences between laboratories.

Disclosure

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Introduction

High-resolution manometry (HRM) is an invasive and technically demanding procedure. Despite the existence of a well-established standard protocol, technically imperfect studies are common and may reduce diagnostic certainty.

Aims & Methods

The aim of this study was to develop a practical and feasible quality score for HRM that correlates the technical quality of the study with the reliability of the diagnosis.
A 10-point quality score was developed based on seven quality indicators: catheter passage across the esophagogastric junction (EGJ), evaluable resting pressures, valid wet swallows, completion of multiple rapid swallows (MRS) and rapid drink challenge (RDC), upright swallows, and absence of artifacts.
The obtained score was used to classify manometric studies into five diagnostic reliability categories: 1) 0–2 points: Uninterpretable manometry, 2) 3–4 points: Deficient manometry with low diagnostic reliability, 3) 5–6 points: Deficient manometry with moderate diagnostic reliability, 4) 7–8 points: Deficient manometry with high diagnostic reliability, 5) 9–10 points: Excellent manometry allowing a certain diagnosis
An initial exploratory evaluation was conducted by two observers (one high-experience, one low-experience observer) who prospectively reviewed 90 HRM studies. A revised version of the score was subsequently implemented and applied in a second evaluation round. In addition to assigning a final quality score, each observer provided the manometric diagnosis of each revised HRM according to Chicago IV classification (CC4.0) and rated the diagnostic confidence level (high, medium, low reliability). In case of disagreement, a third expert adjudicated.

Results

Initial agreement on quality score classification was reached in 30 cases (Cohen’s kappa=0.274) using the original score, improving to 67 out of 90 studies when the revised version was used (Cohen’s kappa=0.718). The main sources of disagreement in the remaining 23 studies were the number of valid swallows (12 studies) and the presence of intragastric pressurization (8 studies). Further evaluation by the expert supported the high-experience observer in 13 cases and the low-experience observer in 5; no consensus was reached in five studies. Overall, 85% of the studies were scored as high-quality studies (score≥7). Diagnostic confidence was rated as high in 86 % of the cases, medium in 14 %, and no cases were rated as low confidence.
There was a good association between quality score and diagnostic confidence among the observers. Hence, 90 % of the studies rated as high-quality studies had a high confidence rate in the diagnostic accuracy, and 62 % of the low-quality studies had a medium level of confidence (p<0.001).
Despite some uncertainty, the two observers agreed on diagnosis in 82 studies (disagreement occurred in two low-quality studies and six high-quality studies). Following expert adjudication, full consensus in diagnosis was reached in all 90 studies. Notably, most of the diagnoses were normal motility or ineffective esophageal motility (86 %), while only 10 % were classified as major motility disorders. Four patients had inconclusive diagnoses according to CC4.0 (two low-quality and two high-quality studies).

Conclusion

A new developed quality score appears to be a valuable tool for assessing HRM study quality and supporting final diagnostic accuracy. Ongoing larger studies aim to determine its potential in clinical practice.

Introduction

Esophageal motility disorders are common in the clinical practice, with impact in patient’s quality of life. High-resolution esophageal manometry (HREM) is the gold standard for evaluation of patients with functional esophageal disorders. The Chicago Classification offers a standardized approach HREM, reducing bias and enabling a precise diagnosis of these disorders. Despite these, HREM remains a complex exam, both in data analysis and in accessibility. This proof-of-concept study aims to develop and validate an artificial intelligence model for identification of motility disorders in HREM according to the Chicago Classification.

Aims & Methods

618 HREM exams from two different devices and three centers from Spain and the United States of America were used for model development. Several machine learning models were trained and evaluated for detection of motility disorders. The exams were classified according to the Chicago Classification 4.0, based on a consensus reached by two independent HREM experts. The training and testing dataset were divided in a 80%/20% patient split design based on label frequency. Models’ performance was evaluated through their accuracy and area under the receiver-operating characteristic curve (AUC-ROC).

Results

The GradientBoostingClassifier model outperformed the remaining machine learning models with an accuracy of 94.2% and an AUCROC of 0.921 for identifying disorders of esophagogastric junction outflow. The xGBClassifier model detected disorders of peristalsis with an accuracy of 80.9% and an AUC-ROC of 0.871.

Conclusion

In this pilot study with integration of exams from different devices and demographic contexts, several machine learning models accurately identified disorders of the esophagogastric junction outflow and peristalsis in HREM according to Chicago Classification.
The integration of AI into the study of esophageal motility disorders through HREM-driven diagnosis is expected to revolutionize the way these conditions are managed, optimizing both exam accuracy and accessibility, transforming patient management.

Introduction

According to guidelines, in order to strictly diagnose esophageal motility disorders, besides achalasia, high resolution manometry (HRM) findings should be documented in both the upright and the supine position. A common finding among patients with Gastro-Esophageal Reflux Disease GERD submitted to manometry is ineffective esophageal motility (IEM). The clinical impact of such a diagnosis in this setting is ambiguous though it may denote future disturbance of peristaltic reserve even if until now only inadequate response to multiple rapid swallows (MRS) has been correlated to post anti-reflux surgery dysphagia.

Aims & Methods

We aimed to evaluate differences in esophageal contractility in different positions in patients with definite GERD.We included consecutive patients with definite GERD according to Acid Exposure Time (>6%) submitted simultaneously to 24 hours pH impedance off PPI study and HRM in both the upright and supine position. Patients with previous esophago-gastric surgeries as also patients diagnosed with motility disorders besides IEM/absent contractility according to Chicago 4 guidelines were excluded.

Results

In total 49 patients (M/F:26 (53.1%)/23 (46.9%), mean age:51±14) were included. The main referral reason was typical reflux symptoms in 37/49 (75.5%) patients while 8/49 (16.3%) reported dysphagia. Mean Distal Contractile Integral (DCI) was significantly reduced in the upright position (1629.2±1175.6 mm²/s/mmHg) vs supine position (2762.4±2710.4 mm²/s/mmHg), p=0.010. The rate of total ineffective swallows in the upright position was significantly increased in the upright position (29.0%) vs the supine (12.3%), p=0.010 as was also the rate of weak contraction (10.3% vs 3.1%, p=0.033 ) and marginally not of absent contractions (17.0% vs 8.3%, p=0.078). The rate of diagnosis of IEM/absent contractility was doubled in the upright position (8/49, 16.3%) vs in the supine position (4/49, 8.2%) (k-value:0.473, p=0.001). Inadequate post MRS contraction was observed in 9/49 (18.4%) and more specifically among 3/4 (75%) patients with IEM/absent contractility diagnosis in the supine position (k:-0.436, p=0.002) vs 4/8 (50%) in the upright position (k:-0.361, p=0.011). Dysphagia was not correlated to diagnosis of IEM/absent contractility neither in the supine (p=0.675) nor the upright position (p=0.586).

Conclusion

Upright position in HRM is correlated to a decreased mean DCI and an increased rate of ineffective esophageal contractions leading to an increased rate of diagnosis of IEM/absent contractility. Such a diagnosis in the upright position is correlated in a lesser extent to inadequate post-MRS swallow and not correlated to symptom of dysphagia. Until new data arise such an overdiagnosis among patients with GERD may be misleading and therefore the procedure in such patient may be better to be undertaken only in the supine position.

Introduction

Evidence is scarce regarding the impact of overweight and obesity on the interpretation of high-resolution esophageal manometry (HREM) parameters. We aimed to investigate whether the presence of overweight and/or obesity influences the HREM parameters.

Aims & Methods

Retrospective cohort study including adult patients undergoing HREM (Manoscan® 36-sensor probe) between 2019-2022, regardless of the indication, with measurement of height and weight at the time of HREM. A HREM diagnosis was obtained according to the Chicago 4.0 classification and the following HREM parameters were collected: esophageal length, length and type of esophagogastric junction (EGJ), presence and extent of hiatal hernia, minimum basal, mean and residual lower esophageal sphincter pressures, basal and residual upper esophageal sphincter pressures, percentage of failed, weak, ineffective, with pressurization, premature, fragmented, intact, hypercontractile swallows and mean and after multiple rapid swallows distal contractile integral. Body mass index (BMI) was calculated, and patients were categorized as underweight (<18.5), normal weight (18.5-24.9), overweight (25-29.9) and obesity (≥30). The relationship between BMI and its categories with the HREM parameters was evaluated.

Results

A total of 249 patients were included, mostly women (59.8%) with a mean age of 56 ± 14 years. The median BMI was 26 (IQR 5) kg/m2 and 115 (46.2%) patients were overweight, 91 (45.7%) normal weight and 43 (17.3%) obese. A normal HREM (51.8%), followed by ineffective esophageal motility (21.7%) and EGJ outflow obstruction (8.8%) were the most frequent HREM diagnoses. There were no statistically significant differences between the presence of overweight and/or obesity and the HREM parameters evaluated, regardless of the HREM diagnosis.

Conclusion

Overweight and obesity do not seem to influence HREM parameters, so its interpretation should not be influenced by these factors.

Introduction

Based on the Chicago classification, HREM diagnosis is classically based on metrics obtained with wet swallows carried out in the supine position. However, both patients and physicians often feel that this is not a physiological position to conduct the test as it may not translate to the real world experience. With the patient in the upright/sitting position, the test would more closely simulate real-life behaviour and may be safer for elderly patients at risk of aspiration.

Aims & Methods

In an Asian tertiary centre, a total of 104 patients had undergone high resolution esophageal manometry (HREM) with retrospective data analysis comparing both conventional supine position with the upright position. The latter is generally favoured by all patients as this represents the physiological posture during meals.

Results

Using 2-tailed paired sample T-test, comparison across all cases showed a consistently lower median Integrated Relaxation Pressure (IRP) [6.0 mmHg vs to 8.7 mmHg; p <0.01] and lower mean Distal Contractile Integral (DCI) [1463 mmHg/cm/sec vs 1864 mmHg/cm/sec; p =0.014] in the upright posture compared to supine position although the mean Distal Latency (DL) difference was not significant [6.21secs vs 6.27 secs; p =0.491]. During upright and supine position comparison respectively, subgroup analysis on subjects with normal HREM diagnosis showed even lower median IRP [4.9 mmHg vs 7.5 mmHg; p <0.01] and lower mean DCI results [1436 mmHg/cm/sec vs 1695 mmHg/cm/sec; p <0.01] with mean DL in this subgroup showing no significant statistical difference [6.29 secs vs 6.38secs; p=0.545]. The final HREM diagnosis in upright position is concordant with the conventional supine position up to 81.7% and showed an even higher concordance in terms of management similarity up to 98.1%. Only 2 cases (2/104) showed a significant discordance between supine and upright HREM diagnosis [normal HREM vs esophagogastric juntion –outflow obstruction(EGJ-OO) and hypercontractile esophagus vs normal HREM]. Minor diagnostic discordance [normal HREM vs ineffective esophageal motility (IEM)] was noted in 17/104 cases which had no major clinical impact on patients and may be overcome by adopting a lower cut-off for mean DCI for upright group.

Conclusion

In patients who are unable to perform HREM in supine position, adopting the upright position shows a high clinical concordance and may be considered a more physiological approach in the HREM protocol.

References

Riva CG, Siboni S, Ferrari D, Sozzi M, Capuzzo M, Asti E, Ogliari C, Bonavina L. Effect of Body Position on High-resolution Esophageal Manometry Variables and Final Manometric Diagnosis. J Neurogastroenterol Motil. 2020 Jul 30;26(3):335-343. doi: 10.5056/jnm20010. PMID: 32606256; PMCID: PMC7329148.

Introduction

Delayed gastric emptying (GE) is a necessary condition for the diagnosis of gastroparesis (1). Motor alterations leading to delayed GE remain poorly identified and are not assessed in routine care. High-resolution antroduodenal manometry (HR-ADM) allows precise characterization of antral, pyloric, and duodenal motility (2). However, HR-ADM has not been assessed in delayed GE.

Aims & Methods

We aimed to identify motility alterations related to delayed GE. Consecutive patients referred for HR-ADM for dyspeptic symptoms performed a concurrent GE breath test with 13C-octanoic acid. HR-ADM involved 36 sensors 1 cm apart placed across the pylorus, with a commercially available probe. Interdigestive and postprandial periods were identified. Antral, pyloric, and duodenal motor profiles were analyzed recording the frequency, amplitude, and propagative nature of contractions. The contractile integral was also measured for each period. Plots of patients with normal and delayed GE, based on the result of the breath test, were compared.

Results

Sixty patients underwent both HR-ADM and GE tests. Twenty-five and 35 patients had delayed and normal GE, respectively. Antral and duodenal motor profiles were not different between the two groups during the interdigestive period, whether during phase II or phase III of the migrating motor complex. The basal pyloric pressure was not different between patients with or without delayed GE. During the postprandial period, a lower frequency of antral contractions was associated with delayed GE (2.22 vs 1.39 contractions/min; p=0.002), but no difference in the amplitude of antral contractions was observed. No difference in duodenal contractions was observed. Finally, the pyloric region was identified in all the patients, and pylorospasms, defined as 3 min of repeated isolated pyloric contractions, were more frequent in patients with delayed GE (32.0% vs 5.7%; p=0.02) during the postprandial period. Manometric alterations in the postprandial period were observed in 72% of the patients with delayed GE, with a low frequency of antral contractions, defined as less than 1 contraction/min, in 56% of the patients.

Conclusion

Using HR-ADM, patients with delayed GE displayed different postprandial antro-pyloric motility as compared with patients with normal GE. HR-ADM could, therefore, be useful in the future to better select patients for treatments targeting the pylorus.

References

1. Camilleri M, Sanders KM. Gastroparesis. Gastroenterology 162: 68-87.e1, 2022. doi: 10.1053/j.gastro.2021.10.028.
2. Desipio J, Friedenberg FK, Korimilli A, Richter JE, Parkman HP, Fisher RS. High-resolution solid-state manometry of the antropyloroduodenal region. Neurogastroenterol Motil 19: 188–195, 2007. doi: 10.1111/j.1365-2982.2006.00866.x.