A Comparison between Chicago Classification Versions 3.0 and 4.0 and Their Impact on Manometric Diagnoses in Esophageal High-Resolution Manometry Cases

High-resolution manometry (HRM) facilitates the detailed evaluation of esophageal motility. In December 2020, Chicago classification (CC) version 4.0 introduced modifications to improve consistency and accuracy. We conducted this study to compare the differences in the interpretations of HRM examinations between CC 3.0 and 4.0. Consecutive HRM records at a Taiwan tertiary medical center, including wet swallows and MRS performed in both supine and sitting positions from October 2019 to May 2021, were retrospectively reviewed and analyzed using both CC versions 3.0 and 4.0. A total of 105 patients were enrolled, and 102 patients completed the exam, while three could not tolerate HRM sitting up. Refractory gastroesophageal reflux disease (GERD) symptoms (n = 65, 63.7%) and dysphagia (n = 37, 36.3%) were the main indications. A total of 18 patients (17.6%) were reclassified to new diagnoses using CC 4.0. Of the 11 patients initially diagnosed with absent contractility, 3 (27.3%) were reclassified as having Type 1 achalasia. Of the 18 patients initially diagnosed with IEM, 6 (33.3%) were reclassified as normal. The incidence of diagnosis changes was similar in both the dysphagia and refractory GERD symptoms groups (21.6% versus 15.3%, p = 0.43). The use of CC 4.0 led to changes in the diagnoses of esophageal motility disease, irrespective of examination indications. Early adoption improves the accuracy of diagnoses and affects patient management.

Chicago Classification Version 4.0 Improves Stratification of Ineffective Esophageal Motility Patients into Clinically Meaningful Subtypes: A Two-Center International Study

The 4th iteration of the Chicago Classification (CC v4.0) for esophageal motility disorders offers more restrictive criteria for the diagnosis of Ineffective Esophageal Motility (IEM) compared to version 3.0 (CC v3.0). In light of the updated criteria for IEM, we aimed to characterize and compare the patients who retained their IEM diagnosis to those who were reclassified as normal motility, and to evaluate the clinical impact of the newly introduced CC v4.0. We performed a retrospective case-control study. We included all individuals who underwent a high-resolution manometry (HRM) between 2020 and 2021 at two centers. Consecutive studies reported as IEM according to the CC v3.0 were reanalyzed according to the CC v4.0. We compared demographics, clinical, manometry, and pH-monitoring parameters. Out of 452 manometry studies, 154 (34%) met criteria for IEM as per the CC v3.0 (CC v3.0 IEM group). Of those, 39 (25%) studies were reclassified as normal studies according to the CC v4.0 (CC v4.0 normal group), while the remaining 115 studies (25% of the overall cohort) retained an IEM diagnosis (CC v4.0 IEM group). The CC v4.0 normal group had more recovered contractions during solid swallows (p = 0.01), less ineffective swallows (p = 0.04), and lower acid exposure time (p = 0.02) compared to the CC4.0 IEM group. Under CC v4.0 criteria, fewer patients are diagnosed with IEM. Those diagnosed with IEM had worse esophageal function and higher acid burden. Though further studies are needed to confirm these findings, our results indicate that CC v4.0 criteria restrict the IEM diagnosis to a more clinically meaningful population.

Comparison of Diagnosis of Esophageal Motility Disorders by Chicago Classification Versions 3.0 and 4.0

Background/Aims

We aim to investigate the diagnostic accuracy and differences between Chicago classification version 3.0 (CC v3.0) and 4.0 (CC v4.0).

Methods

Patients who underwent high-resolution esophageal manometry (HRM) for suspected esophageal motility disorders were prospectively recruited between May 2020 and February 2021. The protocol of HRM studies included additional positional change and provocative testing designed by CC v4.0.

Results

Two hundred forty-four patients were included. The median age was 59 (interquartile range, 45-66) years, and 46.7% were males. Of these, 53.3% (n = 130) and 61.9% (n = 151) were categorized as normalcy by CC v3.0 and CC v4.0, respectively. The 15 patients diagnosed of esophagogastric junction outflow obstruction (EGJOO) by CC v3.0 was changed to normalcy by position (n = 2) and symptom (n = 13) by CC v4.0. In seven patients, the ineffective esophageal motility (IEM) diagnosis by CC v3.0 was changed to normalcy by CC v4.0. The diagnostic rate of achalasia increased from 11.1% (n = 27) to 13.9% (n = 34) by CC v4.0. Of patients diagnosed IEM by CC v3.0, 4 was changed to achalasia based on the functional lumen imaging probe (FLIP) results by CC v4.0. Three patients (2 with absent contractility and 1 with IEM in CC v3.0) were newly diagnosed with achalasia using a provocative test and barium esophagography by CC v4.0.

Conclusions

CC v4.0 is more rigorous than CC v3.0 for the diagnosis of EGJOO and IEM and diagnoses achalasia more accurately by using provocative tests and FLIP. Further studies on the treatment outcomes following diagnosis with CC v4.0 are needed.

The Relationship Between Vocal Fold Mobility Disorders and Ineffective Esophageal Motility

OBJECTIVE

Deglutition, speech production, and airway protection are extraordinarily complex, interrelated functions that are coordinated, in large part, by the motor and sensory innervation of CN X. Previous studies assessing the relationship between neurogenic voice disorders and dysphagia have focused on the risk of aspiration due to glottic insufficiency and the association of vocal fold hypomobility (VFH) with systemic neurologic disease. The purpose of this study was to investigate the relationship between VFH disorders and ineffective esophageal motility (IEM).

METHODS

Adult voice patients who underwent laryngeal electromyography (LEMG) and dual 24-hour pH impedance with high-resolution manometry (HRM) testing were included in the study. Subjects were assigned to one of two groups based on the presence or absence of moderate-to-severe RLN and/or SLN VFH (Mo-SLNH/RLNH) using results from six muscle LEMG tests. In subjects with Mo-SLNH/RLNH, there was 0-60% muscle recruitment on LEMG, whereas control subjects in the non-Mo-SLNH/RLNH group demonstrated 61-100% muscle recruitment. Analysis of mild-to-severe VFH (80% muscle recruitment or less) was also performed in a similar manner. The prevalence of IEM, defined using Chicago Classification Version 4.0 (CCv4.0), was compared between groups, as were HRM parameters.

RESULTS

One hundred sixty-two subjects were included (37.7% male/62.3% female, mean age of 43.88 ± 17.285). No differences in IEM prevalence were found when stratifying for cases of mild-to-severe VFH. However, there was significantly higher percentage of IEM in those with Mo-SLNH/RLNH. Mo-SLNH/RLNH subjects demonstrated higher rates of weak swallows and inefficient swallows, as well as lower IBP and UES residual pressures on HRM.

CONCLUSIONS

Patients with Mo-SLNH/RLNH demonstrated a significantly higher prevalence of IEM. Those with mild-to-severe VFH did not. Higher rates of ineffective and weak swallows, and lower IBP and UES residual pressures among Mo-SLNH/RLNH subjects suggest a possible connection between Mo-SLNH/RLNH and IEM disorders. These manometric differences were more prominent with sub-stratification of the Mo-SLNH/RLNH group by IEM. Additional research is advised.

Identifying spastic variant of type II achalasia after treatment with high-resolution manometry and FLIP Panometry

BACKGROUND

Panesophageal pressurization (PEP) defines type II achalasia on high-resolution-manometry (HRM) but some patients exhibit spasm after treatment. The Chicago Classification (CC) v4.0 proposed high PEP values as predictor of embedded spasm, yet supportive evidence is lacking.

METHODS

Fifty seven type II achalasia patients (47 ± 18 years, 54% males) with HRM and LIP Panometry before and after treatment were retrospectively identified. Baseline HRM and FLIP studies were analyzed to identify factors associated with post-treatment spasm, defined on HRM per CC v4.0.

RESULTS

Seven patients (12%) had spasm following treatment (peroral endoscopic myotomy 47%; pneumatic dilation [PD] 37%; laparoscopic Heller myotomy 16%). At baseline, greater median maximum PEP pressure (MaxPEP) values on HRM (77 vs 55 mmHg, p = 0.045) and spastic-reactive contractile response pattern on FLIP (43% vs 8%, p = 0.033) were more common in patients with post-treatment spasm while absent contractile response on FLIP was more common in patients without spasm (14% vs 66%, p = 0.014). The strongest predictor of post-treatment spasm was the percentage of swallows with MaxPEP ≥70 mmHg (best cut-off: ≥30%), with AUROC of 0.78. A combination of MaxPEP <70 mmHg and FLIP 60 mL pressure < 40 mmHg identified patients with lower rates of post-treatment spasm (3% overall, 0% post-PD) compared to those with values above these thresholds (33% overall, 83% post-PD).

CONCLUSIONS

High maximum PEP values, high FLIP 60 mL pressures and contractile response pattern on FLIP Panometry prior to treatment identified type II achalasia patients more likely to exhibit post-treatment spasm. Evaluating these features may guide personalized patient management.

Long-term outcomes of peroral endoscopic myotomy for Chicago classification type I vs type III achalasia in treatment-naive patients

The efficacy of peroral endoscopic myotomy (POEM) for achalasia has potential associations with Chicago classification by high-resolution manometry (HRM). Type II achalasia demonstrates the best response to POEM of all subtypes, while there remain controversies between type I and type III. Moreover, previous treatment history might cause discrepancy in direct comparison. We aimed to compare the clinical outcome of POEM for type I vs type III in treatment-naive patients. In total, 82 patients with type I or type III achalasia (45 type I, 37 type III) from February 2015 to December 2018 were enrolled and POEM was carried out as the initial treatment. Clinical success, change of Eckardt scores and HRM parameters were analyzed and compared between type I and type III group. About, 43 (95.6%) patients and 34 (91.9%) patients in type I and type III group acquired the clinical success (P = 0.821). Eckardt score and HRM results after POEM treatment decreased significantly in either group (P<0.01). Compared to type III group, higher reduction rates of Eckardt score (type I vs type III, 78.6 vs 66.9%, P = 0.034) and basal LES pressure (type I vs type III, 58.9 vs 40.4%, P = 0.040) were observed in type I group. Type I achalasia patients showed better response to POEM with more favorable clinical remission in Eckardt score and HRM outcomes than type III.

The Supportive Role of Provocative Maneuvers and Impedance Clearance in Detecting Ineffective Esophageal Motility

BACKGROUND

Ineffective esophageal motility (IEM) is one of the most common esophageal motility disorders. However, the definition of IEM has evolved. Chicago classification version 4.0 (CCv4.0) made IEM parameters more stringent with greater than 70% of ineffective wet swallows (WS) necessary to diagnose conclusive IEM. Of the ineffective swallows, 50-70% are deemed "inconclusive cases". This study sought to determine whether provocative maneuvers, including multiple rapid swallows (MRS) and apple viscous swallows (AVS), and impedance clearance can provide supportive information for inconclusive IEM disorders based on CCv4.0.

METHODS

Esophageal motility data on 100 patients were analyzed. All patients completed WS and at least one additional swallow test (MRS and/or AVS). Patients were classified as having conclusive IEM, inconclusive IEM, or normal motility. IEM features detected on MRS/AVS and incomplete bolus clearance were recorded. Percentage of agreement between IEM features and incomplete bolus clearance was calculated for each motility group.

RESULTS

Ten patients had conclusive IEM, nine had inconclusive IEM, and 32 had normal motility. There was 70% agreement between IEM features and incomplete bolus clearance with conclusive IEM, 33% agreement with inconclusive IEM, and 9% agreement with normal motility. There was significantly more agreement in the conclusive and inconclusive IEM groups than in the normal motility group (P = 0.0003).

CONCLUSIONS

Combinational follow-up testing with provocative maneuvers and impedance clearance may assist with risk stratification of IEM patients and assist in further management of inconclusive IEM. MRS and AVS can detect unique IEM features that may help with preoperative management of inconclusive IEM.

Chicago classification v4.0 protocol improves specificity and accuracy of diagnosis of oesophagogastric junction outflow obstruction

BACKGROUND

Chicago classification version 4.0 (CCv4.0) introduced stringent diagnostic criteria for oesophagogastric junction outflow obstruction (EGJOO), in order to increase the clinical relevance of the diagnosis, although this has not yet been demonstrated.

AIMS

To determine the prevalence of EGJOO using CCv4.0 criteria in patients with CCv3.0-based EGJOO, and to assess if provocative manoeuvres can predict a conclusive CCv4.0 diagnosis of EGJOO.

METHODS

Clinical presentation, high resolution manometry (HRM) with rapid drink challenge (RDC), and timed barium oesophagogram (TBE) data were extracted for patients diagnosed with EGJOO as per CCv3.0 between 2018 and 2020. Patients were then re-classified according to CCv4.0 criteria, using clinically relevant symptoms (dysphagia and/or chest pain), and abnormal barium emptying at 5 min on TBE. Receiver operating characteristic (ROC) analyses identified HRM predictors of EGJOO.

RESULTS

Of 2010 HRM studies, 144 (7.2%) fulfilled CCv3.0 criteria for EGJOO (median age 61 years, 56.9% female). Upon applying CCv4.0 criteria, EGJOO prevalence decreased to 1.2%. On ROC analysis, integrated relaxation pressure during RDC (RDC-IRP) was a significant predictor of a conclusive EGJOO diagnosis by CCv4.0 criteria (area under the curve: 96.1%). The optimal RDC-IRP threshold of 16.7 mm Hg had 87% sensitivity, 97.1% specificity, 95.7% negative predictive value and 91.3% positive predictive value for a conclusive EGJOO diagnosis; lower thresholds (10 mmHg, 12 mmHg) had better sensitivity but lower specificity.

CONCLUSION

CCv4.0 criteria reduced the prevalence of EGJOO by 80%, thereby refining the diagnosis and identifying clinically relevant outflow obstruction. Elevated RDC-IRP can predict conclusive EGJOO per CCv4.0.

Pitfalls in the Interpretation of Chicago Classification for Esophageal Motility Disorders

High-resolution manometry permitted the creation of the Chicago classification, that is the categorization for esophageal motility disorders most currently used. Despite its wide acceptance, there are few pitfalls for the correct interpretation of the tests. This technique review illustrates some difficult cases that may lead to misinterpretation of the results. Difficult cases are analyzed, such as the distinction of: (1) esophagogastric junction morphology and lower esophageal sphincter excursion, (2) intrabolus pressure pattern or common cavity, (3) hypercontractile esophagus (jackhammer) and achalasia type III, (4) absent contractility and severe ineffective esophageal motility or achalasia type I, and (5) simultaneous distal esophageal spasm and ineffective esophageal motility.

Hard to Swallow Results

The American Neurogastroenterology and Motility Society (ANMS) proposed quality measures (QMs) for performance and interpretation of esophageal manometry (EM). We implemented a quality improvement (QI) study at a large community hospital to assess and improve procedural adherence and interpretation of EM studies based on the ANMS QMs using the Chicago Classification 3.0 (CC) Guidelines. For pre-intervention, three motility independent reviewers reinterpreted 60 EM studies conducted by community gastroenterologists without Tier II-III motility training from October to December 2018 for compliance with pre-procedural, procedural, and data interpretation ANMS QMs. In December 2018, we developed a pre-procedural form, educated nurses on EM procedural compliance, and provided preliminary pre-intervention results to gastroenterologists along with literature utilizing the CC 3.0 Guidelines. For post-intervention, we reinterpreted 54 EM studies from January to August 2019 and investigated whether they met QMs for data interpretation with respect to the CC Guidelines and resulted in appropriate treatment. We found a statistically significant improvement in procedural compliance among nursing staff for 30 s of swallows (76% post-intervention versus 12% pre-intervention, p < 0.001) and 7 evaluable swallows (94% post-intervention versus 53% pre-intervention, p < 0.001). However, quality metrics within data interpretation by physicians post-intervention showed mixed results. An incorrect diagnosis was made in 50% (n = 27)) of studies with 72% (n = 39) having at least one missing item based on the CC. The most missed diagnosis was fragmented peristalsis (30%, n = 29). Among the 39% (n = 21) of surgery referrals, 24% (n = 5) were incorrectly referred. Our study shows poor data interpretation by community gastroenterologists without formal motility training despite adequate performance by nursing staff. This further supports the need for a national ANMS certification process for formal HRM education.

Clinical significance of esophagogastroduodenoscopy in patients with esophageal motility disorders

OBJECTIVES

The first aim of this study was to elucidate the detection rate of esophagogastroduodenoscopy (EGD) in patients complaining of dysphagia with esophageal motility disorders; the second was to clarify the useful parameters of EGD associated with esophageal motility disorders.

METHODS

Participants included 380 patients who underwent EGD before high-resolution manometry (HRM) for dysphagia. EGD findings were investigated according to the following five parameters: resistance when passing through the esophagogastric junction (EGJ), residue in the esophageal lumen, esophageal dilation, and spastic and nonocclusive contractions. HRM diagnoses were based on the Chicago classification (v3.0).

RESULTS

The percentage of abnormal EGD findings was 64.4% among patients with esophageal motility disorders, and the results differed for each esophageal motility disorder. The rate of abnormal EGD for both EGJ outflow obstruction and major disorders of peristalsis was significantly higher than that for manometrically normal subjects. On multivariate analysis, resistance when passing through EGJ, residue in the esophageal lumen, spastic and nonocclusive contraction were significantly associated with esophageal motility disorders. The sensitivity, specificity, positive predictive value, and negative predictive value of these parameters for detection of esophageal motility disorders were 75.1%, 86.6%, 84.8% and 77.8%, respectively.

CONCLUSION

Esophagogastric junction outflow obstruction and major disorders of peristalsis can be screened with EGD. Among several endoscopic parameters, resistance when passing through EGJ, residue in the esophageal lumen, spastic and nonocclusive contraction are considered significantly useful indicators.

Type II achalasia is associated with a comparably favorable outcome following per oral endoscopic myotomy

Per oral endoscopic myotomy (POEM) is a safe and effective treatment for esophageal motility disorder in treatment-naïve patients as well as salvage therapy. Though type II achalasia, compared to other subtypes, is reported to have a more favorable outcome with pneumatic dilation (PD) or Heller myotomy (HM), it is unclear whether achalasia subtype predicts symptom response to POEM. We aimed to evaluate whether type II achalasia is associated with a comparably favorable outcome following POEM. We performed a retrospective review of patients with esophageal motility disorder who were referred for POEM from April 2014 to June 2017. The main outcome was clinical success based on Eckardt score ≤3 and its association with subtype and safety. A total of 63 patients (mean age 51 years [SD 15]; 63% male) underwent a total of 68 POEMs with median of 263 days follow-up. Of these, 45 (71.3%) patients were type II achalasia. In all, 29 (46%) patients were treatment-naïve and 34 (54%) patients had previous endoscopic or surgical therapy including botulinum toxin injection in 16 (25%), PD in 10 (16%), both botulinum toxin injection and PD in 8 (13%) and HM in 3 (5%). Technical success was 100% and clinical success was achieved in 51 (81%) patients. The rate of clinical success was higher in patients with type II achalasia compared to the other subtypes (88.9% vs. 61.1% [P = 0.028]) and type II achalasia patients required fewer redo POEM (2.2% vs. 22.2% [P = 0.021]). Multivariate logistic regression analysis demonstrated the positive prediction of clinical success for type II achalasia following POEM (P = 0.046). As observed with PD and HM, type II achalasia was associated with a favorable clinical outcome following POEM.

Changes in the Treatment of Primary Esophageal Motility Disorders Imposed by the New Classification for Esophageal Motility Disorders on High Resolution Manometry (Chicago Classification 4.0)

The Chicago Classification is the most used classification for primary esophageal motility disorders (PEMD). This classification was recently updated to the 4.0 version. This opinion piece focuses on the possible implications for the treatment of PMED determined by the new classification. Chicago Classification 4.0 included two new concepts for the diagnosis of achalasia: (1) type III achalasia diagnosis demands 100% absent peristalsis defined as either failed peristalsis or spasm; (2) “inconclusive diagnosis of achalasia” was added as a possibility. Both may decrease unnecessary treatment. Esophagogastric junction outflow obstruction, distal esophageal spasm, and hypercontractile esophagus were only considered clinically significant when correlated to supportive testing and relevant clinical symptoms and in the absence of gastroesophageal reflux disease. This may decrease the surge of treatment, especially peroral endoscopic myotomy, based solely on manometric diagnosis.

The effects of different postures and provocative swallow materials on the normative Chicago 3.0 metrics in a healthy Asian population

BACKGROUND AND AIM

Variations in the Chicago 3.0 normative metrics may exist with different postures and with different provocative swallow materials in a healthy Asian population.

METHOD

Eligible healthy Malay volunteers were invited to undergo the high-resolution esophageal manometry (inSIGHT Ultima, Diversatek Healthcare, Milwaukee, WI, USA). In recumbent and standing positions, test swallows were performed using liquid, viscous, and solid materials. Metrics including integrated relaxation pressure 4 s (IRP-4 s, mmHg), distal contractile integral (DCI, mmHg s cm), distal latency (DL, s), and peristaltic break (PB, cm) were reported in median and 95th percentile.

RESULTS

Fifty of 57 screened participants were recruited, and 586 saline, 265 viscous, and 261 solid swallows were analyzed. Per-patient wise, in the recumbent position, 95th percentile for IRP-4 s, DCI, DL, and PB were 16.5 mmHg, 2431 mmHg s cm, 8.5 s, and 7.2 cm, respectively. We observed that with each posture, the use of viscous swallows led to changes in DL, but the use of solid swallows led to more changes in the metrics including DCI and length of PB. Compared with a recumbent posture, anupright posture led to lower IRP-4 s and DCI values. Both per-patient analysis and per-swallow analyses yielded almost similar results when comparing the different postures and types of swallows. No major motility disorders were observed in this cohort of asymptomatic population. However, more motility disorders were reported in the upright position.

CONCLUSIONS

Variations in metrics can be observed in different postures and with different provocative swallow materials in a healthy population. The normative Chicago 3.0 metrics are also determined for the Malay population.

European Society for Neurogastroenterology and Motility (ESNM) recommendations for the use of high-resolution manometry of the esophagus

BACKGROUND

Several patients in gastroenterology practice present with esophageal symptoms, and in case of normal endoscopy with biopsies, high-resolution manometry (HRM) is often the next step. Our aim was to develop a European consensus on the clinical application of esophageal HRM, to offer the clinician guidance in selecting patients for HRM and using its results to optimize clinical outcome.

METHODS

A Delphi consensus was initiated with 38 multidisciplinary experts from 16 European countries who conducted a literature summary and voting process on 71 statements. Quality of evidence was evaluated using grading of recommendations assessment, development, and evaluation (GRADE) criteria. Consensus (defined as >80% agreement) was reached for 33 statements.

RESULTS

The process generated guidance on when to consider esophageal HRM, how to perform it, and how to generate the report. The Delphi process also identified several areas of uncertainty, such as the choice of catheters, the duration of fasting and the position in which HRM is performed, but recommended to perform at least 10 5-ml swallows in supine position for each study. Postprandial combined HRM impedance is considered useful for diagnosing rumination. There is a large lack of consensus on treatment implications of HRM findings, which is probably the single area requiring future targeted research.

CONCLUSIONS AND INFERENCES

A multinational and multidisciplinary group of European experts summarized the current state of consensus on technical aspects, indications, performance, analysis, diagnosis, and therapeutic implications of esophageal HRM.

Evaluation of esophageal motor function in patients with gastroesophageal reflux using multiple rapid swallows

Multiple rapid swallow (MRS) is a complementary test performed during high-resolution esophageal manometry (HREM). The present study was done to assess the MRS findings in patients with gastroesophageal reflux disease (GERD) who have normal peristalsis and minor motility disorders. This is a retrospective analysis from a prospectively maintained database of patients referred for HREM study to our center. The recorded details included age, sex, symptoms with duration, and upper gastrointestinal endoscopy reports. HREM data included basal inspiratory and expiratory pressures, median integrated relaxation pressure, and peristaltic pattern. Three MRS sequences were recorded per patient. The inhibition and contraction phases were interpreted for each MRS sequence. A total of 68 patients (38 normal motility, 30 minor motility disorders) formed the study cohort. Hiatus hernia was common in GERD patients with minor motility disorders (p 0.02). Patients with minor motility disorders were more likely to have poor peristaltic reserve than patients with normal peristalsis (p < 0.05). MRS patterns in inhibition and contraction phases were similar in the three MRS sequences for patients with normal peristalsis, while in patients with minor peristaltic disorders, the inhibition phase was significantly discordant on repetitive MRS (p 0.049). Thus, in GERD patients, those with normal peristalsis were more likely to have normal MRS pattern. On the contrary, those with minor peristaltic disorders had a higher frequency of poor peristaltic reserve and show significant discordance in the inhibition phase of MRS.

The Challenges of Esaphagogastric Junction Outflow Obstruction, Is It Really a Diagnosis? Creating a Systematic Clinical Approach for EGJOO

Esophagogastric junction outflow obstruction (EGJOO) is currently diagnosed according to the Chicago Classification V3 by an elevated median integrated relaxation pressure on high resolution manometry. However, EGJOO may not be an accurate diagnosis, as it may be based on abnormal IRP from an artifact, affected by narcotics, an achalasia variant, or a mechanical cause of obstruction. This heterogenous diagnosis can often lead to unnecessary testing and treatment. The purpose of this study is to develop a stepwise clinical management protocol on how to evaluate EGJOO. Motility studies were reviewed for the last 2 years and 39 patients were diagnosed with EGJOO. Clinical information was reviewed, and patients were classified into six stepwise categories to explain an elevated IRP resulting in EGJOO diagnosis: (1) underlying catheter artifact (2) opioid use (3) achalasia variant (4) jackhammer esophagus with obstruction (5) missed esophageal lesion (ex. Schatzki ring, EOE) and (6) extrinsic compression. 40% (n = 14) of patients with elevated IRP were due to an underlying catheter artifact. 8.6% (n = 3) were due to opioid use. 8.6% (n = 3) were due to achalasia variant. 31.4% (n = 11) were due to jackhammer esophagus with obstruction. 5.7% (n = 2) were due to missed esophageal lesion. 5.7% (n = 2) were due to external compression by cardiomegaly and aortic aneurism. EGJOO is not a diagnostic end point, but a heterogenous category with multiple underlying etiologies. We believe the use of a stepwise approach to these patients can help avoid further unnecessary testing.

Esophagogastric Junction Outflow Obstruction: Current Approach to Diagnosis and Management

PURPOSE OF REVIEW

We summarize the current epidemiology, presentation, diagnostic workup, and treatment of esophagogastric junction outflow obstruction (EGJOO). We also propose a treatment algorithm based upon the literature and our personal clinical experience.

RECENT FINDINGS

EGJOO can be caused by functional obstruction (akin to achalasia), mechanical obstruction, medications, or artifact. High-resolution esophageal manometry is currently the gold standard of diagnosis. Recent research on FLIP (functional lumen imaging probe) and timed barium support use as adjunctive testing. The diagnostic yield of cross-sectional imaging is low. Current diagnostic testing and treatment should be targeted to the suspected underlying etiology and clinical presentation of EGJOO. If functional obstruction is present with significant and persistent dysphagia, and either an abnormal FLIP or timed barium swallow, we consider therapy aimed at LES disruption (similar to achalasia). Pharmacologic therapy has a limited role. More research is needed on diagnostic and treatment modalities.

High-resolution esophageal manometry in pediatrics: Effect of esophageal length on diagnostic measures

BACKGROUND

High-resolution esophageal manometry (HREM), derived esophageal pressure topography metrics (EPT), integrated relaxation pressure (IRP), and distal latency (DL) are influenced by age and size. Combined pressure and intraluminal impedance also allow derivation of metrics that define distension pressure and bolus flow timing. We prospectively investigated the effects of esophageal length on these metrics to determine whether adjustment strategies are required for children.

METHODS

Fifty-five children (12.3 ± 4.5 years) referred for HREM, and 30 healthy adult volunteers (46.9 ± 3.8 years) were included. Studies were performed using the MMS system and a standardized protocol including 10 × 5 mL thin liquid bolus swallows (SBM kit, Trisco Foods) and analyzed via Swallow Gateway (www.swallowgateway.com). Esophageal distension pressures and swallow latencies were determined in addition to EGJ resting pressure and standard EPT metrics. Effects of esophageal length were examined using partial correlation, correcting for age. Adult-derived upper limits were adjusted for length using the slopes of the identified linear equations.

KEY RESULTS

Mean esophageal length in children was 16.8 ± 2.8 cm and correlated significantly with age (r = 0.787, P = .000). Shorter length correlated with higher EGJ resting pressure and 4-s integrated relaxation pressures (IRP), distension pressures, and shorter contraction latencies. Ten patients had an IRP above the adult upper limit. Adjustment for esophageal length reduced the number of patients with elevated IRP to three.

CONCLUSIONS & INFERENCES

We prospectively confirmed that certain EPT metrics, as well as potential useful adjunct pressure-impedance measures such as distension pressure, are substantially influenced by esophageal length and require adjusted diagnostic thresholds specifically for children.

Clinical impact of different cut-off values in high-resolution manometry systems on diagnosing esophageal motility disorders

BACKGROUND

The values of the parameters in the Chicago classification measured by a high-resolution manometry (HRM) system with the Unisensor catheter (Starlet) are significantly different from those measured by the ManoScan. The contraction vigor is categorized by values of the distal contractile integral (DCI) in the Chicago classification v3.0; however, reference values of the DCI in the Starlet and the clinical impact of the different reference values in the Starlet and ManoScan on diagnosing esophageal motility disorders are not known.

METHODS

We evaluated data from a previous report in which ManoScan and Starlet were compared in the same subjects. The DCI values in each system were compared and reference DCI values were calculated. Moreover, diagnoses assessed by Starlet using reference values in ManoScan were compared with those using calculated reference values and those assessed by ManoScan.

RESULTS

There was a significant positive correlation between the DCI values measured by ManoScan and those measured by Starlet (r = 0.80, p < 0.01). Based on a linear functional relationship considering measurement errors, the reference DCI values for diagnosing failed, weak and hypercontractile contraction vigor were calculated as 590.6, 1011.3 and 10,085.8 mmHg-s-cm, respectively, in the Starlet. Therefore, the proposed reference values in the Starlet were 500, 1000 and 10,000 mmHg-s-cm, respectively. When the reference values in the ManoScan were used in the Starlet data, approximately 30% of subjects were diagnosed inappropriately. This issue was resolved using the proposed reference values in the Starlet.

CONCLUSION

Recognizing systemic differences in HRM systems is important.

Utility of Esophageal High-Resolution Manometry in Clinical Practice: First, Do HRM

Esophageal high-resolution manometry (HRM) has advanced the understanding of esophageal motor function and the ability to diagnose and manage disorders of esophageal motility. In this review, we describe the indications for and the technical performance of HRM. The Chicago classification of esophageal motor function, now in its third iteration, streamlines and standardizes the nomenclature and basic interpretation of HRM data depicted as Clouse topographic plots. In clinical practice, HRM is an important diagnostic test for patients with dysphagia as well as patients with suspected gastroesophageal reflux disease (GERD), particularly in those patients with a suboptimal symptomatic response to antisecretory therapy. HRM can support diagnoses such as achalasia, as well as provide evidence for behavioral disorders such as rumination syndrome or supragastric belching with the assistance of postprandial HRM with impedance. Further, the GERD classification of motor function introduces a three-part hierarchical evaluation of esophageal motor function in GERD, highlighting the value of assessment of esophageal contractile reserve through provocative maneuvers during HRM such as multiple rapid swallows.

High resolution manometry and new classification of esophageal motility disorders

AIM

To present application of Chicago classification criteria of esophageal motility disorders defined in high resolution manometry in clinical practice.

MATERIALS AND METHODS

High-resolution manometry is the most exact hi-tech diagnostic method for esophageal motor function disorders according to Chicago classification v3.0. Uniqueness of the method consists in capacity to define integrated quantitative and qualitative metrics of esophageal contractile function and to establish their specific disorders e.g.: change of intrabolus pressure at disorders of esophagogastric junction (EGj) outflow, hypercontractile esophagus, fragmented contractions and weak or failed peristalsis, distal esophageal spasm. Assessment of the type of achalasia subtypes has significant impact on the patients' treatment choice. According to anatomical location of the lower esophageal sphincter and crural diaphragm several morphological types of gastro-esophageal junction are defined that determine severity of gastroesophageal reflux disease. Multiple rapid swallow responses during esophageal high-resolution manometry reflect esophageal body peristaltic reserve and is a predictor of postoperative complications. Differential diagnosis of belching type became possible at combined application of high-resolution manometry and impedance measurement.

RESULTS

CONCLUSION

High-resolution manometry is a fundamental diagnostic test of esophageal motor function disorders. Clinical application of this method significantly expands diagnostic potential and allows to carry out personalized treatment that increases treatment quality.

Esophageal motility disorders: new perspectives from high-resolution manometry and histopathology

High-resolution manometry (HRM) and peroral endoscopic myotomy (POEM) have contributed significantly to the field of esophageal motility disorders in recent years. The development of HRM has categorized various esophageal motility disorders with a focus on a diverse range of manometric anomalies. Additionally, the Chicago classification criteria is widely used for manometric diagnosis. Moreover, POEM was introduced as a minimally invasive radical therapy for achalasia and shows promise for other spastic esophageal motility disorders as well. POEM has also enabled a transluminal endoscopic approach for determining the histology of the esophageal muscle layer, which is expected to assist in elucidating the etiology of disorders associated with esophageal motility. The purpose of this review is to update the diagnosis, pathology, and treatment of esophageal motility disorders, with a focus on the recent advances in this field.

Chicago Classification of Esophageal Motility Disorders: Lessons Learned. Curr Gastroenterol Rep. 2017;19:37. [PMID: 28730503 PMCID: PMC5519653 DOI: 10.1007/s11894-017-0576-7]

PURPOSE OF REVIEW

High-resolution manometry (HRM) is increasingly performed worldwide, to study esophageal motility. The Chicago classification is subsequently applied to interpret the manometric findings and facilitate a diagnosis of esophageal motility disorders. This review will discuss new insights regarding the diagnosis and management using the Chicago classification.

RECENT FINDINGS

Recent studies have demonstrated that high-resolution manometry is superior to conventional manometry, and has a higher sensitivity to diagnose achalasia. Furthermore, the subclassification of achalasia as used in the Chicago classification has prognostic value and can be used to direct treatment. Diagnosis of esophageal spasm has been improved by using the distal latency as diagnostic criterion. Recently, criteria for minor disorders of peristalsis have been sharpened, leading to a lower rate of patients with abnormal results, thereby increasing the relevance of a diagnosis. High-resolution manometry is now considered the gold standard for diagnosis of esophageal motility disorders. The Chicago classification provides a standardized approach for analysis and categorization of abnormalities that has led to a significant increase in our knowledge regarding the diagnosis and management of motility disorders. Further refinement of the classification will be required.

Understanding the Chicago Classification: From Tracings to Patients

Current parameters of the Chicago classification include assessment of the esophageal body (contraction vigour and peristalsis), lower esophageal sphincter relaxation pressure, and intra-bolus pressure pattern. Esophageal disorders include achalasia, esophagogastric junction outflow obstruction, major disorders of peristalsis, and minor disorders of peristalsis. Sub-classification of achalasia in types I, II, and III seems to be useful to predict outcomes and choose the optimal treatment approach. The real clinical significance of other new parameters and disorders is still under investigation.

Distal esophageal spasm with multiple esophageal diverticula successfully treated by peroral endoscopic myotomy

Distal esophageal spasm (DES) is a primary esophageal motility disorder. We encountered a rare case of DES accompanied by multiple esophageal diverticula. A 72-year-old woman complained of prolonged dysphagia and chest pain. A barium esophagogram showed multiple esophageal diverticula and significant contraction of the lower esophagus just above the cardia. Esophagogastroduodenoscopy revealed a corkscrew-like appearance, with spiral contractions and diverticula. High-resolution manometry revealed that the integrated relaxation pressure was normal; premature contractions were observed in ≥20% of the swallowing wave; the distal contractile integral was normal. She was diagnosed with DES according to the Chicago classification v 3.0. As smooth muscle relaxants were not effective, we decided to perform peroral endoscopic myotomy (POEM) to eliminate persistent esophageal contraction. After POEM treatment, her symptoms were markedly improved, and the Eckardt score significantly decreased from 11 points to 1. An esophagogram after POEM showed that barium flowed promptly into the stomach. The multiple esophageal diverticula were considered to be the result of false pulsion diverticulosis caused by excessive internal esophageal pressure, and this represented the most severe form of DES. POEM could be a new curative strategy for the most severe DES cases with multiple diverticula.

Comparison of motor diagnoses by Chicago Classification versions 2.0 and 3.0 on esophageal high-resolution manometry

BACKGROUND

The Chicago Classification (CC) uses high-resolution manometry (HRM) software tools to designate esophageal motor diagnoses. We evaluated changes in diagnostic designations between two CC versions, and determined motor patterns not identified by either version.

METHODS

In this observational cohort study of consecutive patients undergoing esophageal HRM over a 6-year period, proportions meeting CC 2.0 and 3.0 criteria were segregated into esophageal outflow obstruction, hypermotility, and hypomotility disorders. Contraction wave abnormalities (CWA), and 'normal' cohorts were recorded. Symptom burden was characterized using dominant symptom intensity and global symptom severity. Motor diagnoses, presenting symptoms, and symptom burden were compared between CC 2.0 and 3.0, and in cohorts not meeting CC diagnoses.

KEY RESULTS

Of 2569 eligible studies, 49.9% met CC 2.0 criteria, but only 40.3% met CC 3.0 criteria (P<.0001). Between CC 2.0 and 3.0, 82.8% of diagnoses were concordant. Discordance resulted from decreasing proportions of hypermotility (4.4%) and hypomotility (9.0%) disorders, and increase in 'normal' designations (13.0%); esophageal outflow obstruction showed the least variation between CC versions. Symptom burden was higher with CC 3.0 diagnoses (P≤.005) but not with CC 2.0 diagnoses (P≥.1). Within 'normal' cohorts for both CC versions, CWA were associated with higher likelihood of esophageal symptoms, especially dysphagia, regurgitation, and heartburn, compared to truly normal studies (P≤.02 for each comparison).

CONCLUSIONS AND INFERENCES

Despite lower sensitivity, CC 3.0 identifies esophageal motor disorders with higher symptom burden compared to CC 2.0. CWA, which are associated with both transit and perceptive symptoms, are not well identified by either version.

Primary Esophageal Motility Disorders: Beyond Achalasia

The best-defined primary esophageal motor disorder is achalasia. However, symptoms such as dysphagia, regurgitation and chest pain can be caused by other esophageal motility disorders. The Chicago classification introduced new manometric parameters and better defined esophageal motility disorders. Motility disorders beyond achalasia with the current classification are: esophagogastric junction outflow obstruction, major disorders of peristalsis (distal esophageal spasm, hypercontractile esophagus, absent contractility) and minor disorders of peristalsis (ineffective esophageal motility, fragmented peristalsis). The aim of this study was to review the current diagnosis and management of esophageal motility disorders other than achalasia.

Achalasia: It Is Not All Black and White

PURPOSE OF REVIEW

This review aims to shed light on subtleties of achalasia diagnosis, including potential pitfalls that may lead to errors. Optimal methods for assessment of disease severity and the relationship between achalasia and other motility disorders will also be reviewed with an emphasis on recent findings from the literature.

RECENT FINDINGS

Adjunctive testing with viscous substances or larger water volumes should be used routinely as it improves the accuracy of achalasia diagnosis. Chronic opiate use can mimic achalasia. The timed barium swallow remains the best test for assessments of disease severity and prognostication, but the functional lumen-imaging probe, a newer tool which measures esophagogastric junction distensibility using impedance planimetry, is emerging as a potentially more powerful tool for these purposes. Functional esophagogastric junction outflow obstruction is possibly part of the achalasia spectrum. By addressing the potential pitfalls described, and through routine and standardized use of the diagnostic tools mentioned herein, the accuracy of diagnosis, severity assessment, and prognostication of achalasia can be improved.

Characterization of Esophageal Motility Disorders in Children Presenting With Dysphagia Using High-Resolution Manometry

PURPOSE OF REVIEW

The Chicago classification was based on metrics derived from studies in asymptomatic adult subjects. Our objectives were to characterize esophageal motility disorders in children and to determine whether the spectrum of manometric findings is similar between the pediatric and adult populations.

RECENT FINDINGS

Studies have suggested that the metrics utilized in manometric diagnosis depend on age, size, and manometric assembly. This would imply that a different set of metrics should be used for the pediatric population. There are no standardized and generally accepted metrics for use in the pediatric population, though there have been attempts to establish metrics specific to this population. Overall, we found that the distribution of esophageal motility disorders in children was like that described in adults using the Chicago classification. This analysis will serve as a prequel to follow-up studies exploring the individual metrics for variability among patients, with the objective of establishing novel metrics for the pediatric population.

Chicago Classification of Esophageal Motility Disorders: Applications and Limits in Adults and Pediatric Patients with Esophageal Symptoms

The Chicago classification (CC) is most valued for its systematic approach to esophageal disorders and great impact in unifying practice for esophageal manometric studies. In view of the ever-growing wealth of knowledge and experience gained by the expanding use of high-resolution manometry (HRM) in various clinical scenarios, the CC is regularly updated. Its clinical impact and ability to predict clinical outcome, both in adults and pediatrics, will be further promoted by recognizing its current limitations, incorporating new metrics in its diagnostic algorithms and adjusting the HRM protocols based on the clinical question posed. Herein, we discuss the current limitations of the CC and highlight some areas of improvement for the future.

Anatomic abnormalities are common potential explanations of manometric esophagogastric junction outflow obstruction

BACKGROUND

Esophagogastric junction outflow obstruction (EGJOO) is an esophageal motility diagnosis associated with a myriad of conditions. The frequency of EGJOO attributed to anatomic causes compared to idiopathic causes is uncertain. Our study aims to identify the frequency of EGJOO and to compare these two groups.

METHODS

We conducted a case-control study of high-resolution manometry (HRM) studies with a diagnosis of EGJOO performed at a single academic center. EGJOO cases were classified as anatomic (if any potential anatomic cause was identified) or idiopathic. Clinical and manometric characteristics of idiopathic EGJOO were compared with anatomic EGJOO cases.

KEY RESULTS

Criteria for EGJOO were met in 11% of HRM studies. Ancillary studies revealed 21/32 EGJOO cases had potential anatomic causes with a hiatal hernia noted in 15/21 cases of anatomic EGJOO. Idiopathic EGJOO cases met Chicago Classification criteria for hypercontractile esophagus with greater frequency than anatomic cases (p = 0.01). The mean distal contractile integral was significantly greater for idiopathic cases compared to anatomic cases (p = 0.003). Treatments used for EGJOO were varied and usually successful in alleviating symptoms. Patients with anatomic EGJOO related to a hiatal hernia who underwent an antireflux operation did not develop dysphagia postoperatively.

CONCLUSIONS & INFERENCES

EGJOO is a frequently encountered manometric diagnosis, commonly associated with anatomic abnormalities potentially explaining the EGJOO. These findings support current recommendations to pursue ancillary diagnostics to investigate cases of unexplained EGJOO. Cases of idiopathic EGJOO are more likely to have hypercontractility on HRM, possibly suggesting a primary esophageal motility disorder.

High-resolution manometric subtypes as a predictive factor for the treatment of achalasia: A meta-analysis and systematic review

OBJECTIVE

To assess manometric subtypes as predictive factors for the treatment efficacies of pneumatic balloon dilatation (PBD) and laparoscopic Heller myotomy (LHM) in patients with achalasia.

METHODS

A systematic search of the Pubmed, Embase and Cochrane Library database was conducted to identify relevant publications on high-resolution manometric subtypes and different therapies for achalasia with predefined inclusion and exclusion criteria. Data on the success rates after PBD or LHM for different manometric subtypes were extracted. The pooled odds ratio (OR) and 95% confidence interval (CI) for different manometric subtypes were estimated using STATA 13.0.

RESULTS

In all, nine studies met the inclusion criteria. A total of 298 patients having achalasia receiving PBD and 429 undergoing LHM were included in the meta-analysis. The pooled OR between the subtypes of achalasia after PBD or LHM showed that the best and worse treatment outcomes were found in patients with type II and III achalasia, respectively (type I vs type II after PBD: OR 0.16, 95% CI 0.08-0.36, P = 0.000; type I vs type III after PBD: OR 3.64, 95% CI 1.55-8.53, P = 0.003; type II vs type III after PBD: OR 27.18, 95% CI 9.08-81.35, P = 0.000; type I vs type II after LHM: OR 0.26, 95% CI 0.12-0.56, P = 0.001; type I vs type III after LHM: OR 1.89, 95% CI 0.80-4.50, P = 0.148; type II vs type III after LHM: OR 6.86, 95% CI 2.72-17.28, P = 0.000).

CONCLUSION

Type II achalasia shows the best prognosis after PBD and LHM, while type III achalasia has the worst prognosis.

Characterization and follow-up of esophagogastric junction outflow obstruction detected by high resolution manometry

BACKGROUND

Esophagogastric junction outflow obstruction (EGJOO) is a newly described diagnostic entity growing in importance due to the use of high resolution manometry (HRM). There is little knowledge regarding its incidence, etiopathogeny, long-term evolution, and most suitable treatment. Our objective was to increase the awareness of EGJOO to optimize the management of these patients.

METHODS

We conducted a historical (retrospective and prospective) study of patients diagnosed with EGJOO using HRM combined with multichannel intraluminal impedance, comparing their manometric and impedance characteristics with those of a control group. Symptoms, etiology of obstruction, acid exposure, clinical course (and its associated factors), and response to treatment were also evaluated in the EGJOO group.

KEY RESULTS

Forty-four subjects were included (28 patients and 16 controls). Esophagogastric junction outflow obstruction patients presented incomplete esophageal transit more frequently than controls. Patients with structural obstruction had dysphagia more frequently than patients with functional obstruction, and different manometric, impedance, and pH-metric patterns. Over one-third of the EGJOO patients presented a spontaneous resolution of symptoms without EGJOO treatment. In the multivariate analysis, the variables associated with this spontaneous symptomatic resolution included typical symptoms of gastro-esophageal reflux disease or epigastralgia as the main symptom and resting or basal pressure of the upper esophageal sphincter <50 mmHg.

CONCLUSIONS & INFERENCES

The majority of EGJOO patients presented intact peristalsis which may compensate for the lack of EGJ relaxation. In the EGJOO patients presenting favorable factors associated with a spontaneous resolution of symptoms, invasive treatments should be considered with special caution. Structural etiologies are more amenable to management, while the remainder may improve without intervention.

Can high resolution manometry parameters for achalasia be obtained by conventional manometry?

High resolution manometry (HRM) is a new technology that made important contributions to the field of gastrointestinal physiology. HRM showed clear advantages over conventional manometry and it allowed the creation of different manometric parameters. On the other side, conventional manometry is still wild available. It must be better studied if the new technology made possible the creation and study of these parameters or if they were always there but the colorful intuitive panoramic view of the peristalsis from the pharynx to the stomach HRM allowed the human eyes to distinguish subtle parameters unknown or uncomprehend so far and if HRM parameters can be reliably obtained by conventional manometry and data from conventional manometry still can be accepted in achalasia studies. Conventional manometry relied solely on the residual pressure to evaluate lower esophageal sphincter (LES) relaxation while HRM can obtain the Integrated Relaxation Pressure. Esophageal body HRM parameters defines achalasia subtypes, the Chicago classification, based on esophageal pressurization after swallows. The characterization of each subtype is very intuitive by HRM but also easy by conventional manometry since only wave amplitudes need to be measured. In conclusion, conventional manometry is still valuable to classify achalasia according to the Chicago classification. HRM permits a better study of the LES.

Impact of high-resolution manometry on achalasia diagnosis and treatment

Achalasia is a primary neurodegenerative disorder of the esophagus characterized by loss of function of the lower esophageal sphincter (LES) and of esophageal peristalsis, which causes symptoms such as dysphagia, regurgitation, weight loss, and chest pain. Esophageal manometry is the gold standard for the diagnosis of achalasia. The typical manometric features are incomplete relaxation of a frequently hypertensive LES and lack of peristalsis in the tubular esophagus. High-resolution manometry using catheters with 36 solid-state sensors spaced 1cm apart has more and more replaced water-perfused and pull-through manometry. However, the main innovation of this method is the conversion of pressure data into a topographical plot. The data can be modified using interpolation to generate high-resolution esophageal pressure topography (HREPT). HREPT is more sensitive, provides more detailed information, and is easier to perform than conventional manometry. Introduction of HREPT had an impact especially on the diagnosis and management of achalasia. A clinically relevant impact was achieved by the identification of 3 clinical subtypes which seem to predict treatment outcomes. This review analyzes the progress made in the diagnosis and management of achalasia since the recent introduction of HREPT.

Residual lower esophageal sphincter pressure as a prognostic factor in the pneumatic balloon treatment of achalasia

BACKGROUND AND AIMS

Pneumatic balloon dilatation (PD) is a mainstay in achalasia treatment. The aim of this study was to identify predictive factors for successful treatment.

METHODS

We retrospectively reviewed 76 patients with a diagnosis of achalasia who underwent PD from June 2010 to May 2013. Clinical symptoms were assessed using Eckardt score and manometry data were analyzed using resting and relaxation pressure (4sIRP) of lower esophageal sphincter (LES) and the distal contractile integral (DCI), which was calculated for 10 s from the start of deglutition between the upper margin of the LES and lower margin of upper esophageal contraction. Patients with achalasia were classified into three groups based on the Chicago classification.

RESULTS

Among 76 patients, 52 patients received PD, and the treatment was unsuccessful in 9 patients (6 in class I and 3 in class III). When comparing prognostic factors between successful and unsuccessful treatment groups, the mean value for 4sIRP in the unsuccessful treatment group was significantly lower than that in the successful treatment group (P < 0.05). However, no difference was noticed in resting LES pressure, DCI, age, and sex. Furthermore, a lower mean value of 4sIRP was significantly related to unsuccessful treatment of achalasia (odds ratio, 1.092; 95% confidence interval, 1.001-1.191) even after adjustment for a series of confounding factors.

CONCLUSIONS

Lower 4sIRP may be a prognostic indicator for poor treatment outcome after PD.

Normative data of high-resolution impedance manometry in the Chinese population

BACKGROUND AND AIM

Current normative data of high-resolution manometry have been obtained from Western populations, and esophageal motility disorders have been categorized using Chicago classification. However, the utility of high-resolution impedance manometry (HRiM) in the Chinese population has not been evaluated. The study aimed to investigate the normal reference of esophageal motility in healthy volunteers (as defined by Chicago classification) using HRiM.

METHODS

Healthy, fasted volunteers underwent HRiM in a supine position with 10 liquid swallows and 10 viscous swallows. Integrated relaxation pressure (IRP), distal contractile integral (DCI), contractile front velocity (CFV), and distal latency were calculated. The interquartile ranges and the 95th percentile range for each metric were obtained.

RESULTS

Forty-two healthy volunteers were enrolled with 411 total liquid swallows and 398 viscous swallows available for analysis. A 20.5 mmHg of IRP and a 3195 mmHg·s·cm of DCI as the 95th percentile for liquid swallows were established. Using the reference range defined by Chicago classification, 6.3% (26/411) weak peristalsis and 0.7% (3/411) failed peristalsis for liquid swallows were observed; 12 (28.6%, 12/42) and 2 (4.7%, 2/42) individuals were diagnosed as esophagogastric junction outflow obstruction and weak peristalsis for liquid swallows. Compared with liquid swallows, viscous swallows had a decreased IRP (P = 0.000) and CFV (P = 0.000), and an unchanged DCI (P = 0.211).

CONCLUSIONS

HRiM normative data of both liquid and viscous swallows from healthy Chinese volunteers were established. The IRP and CFV were significantly decreased in the viscous swallows compared with those of the liquid swallows.

High-resolution Manometry: Esophageal Disorders Not Addressed by the "Chicago Classification"

The development of the high-resolution esophageal manometry (HRM) and the Chicago classification have improved the diagnosis and management of esophageal motility disorders. However, some conditions have yet to be addressed by this classification. This review describes findings in HRM which are not included in the current Chicago classification based on the experience in our center. This includes the analysis of the upper esophageal sphincter, proximal esophagus, longitudinal muscle contraction, disorders related to gastroesophageal reflux disease and respiratory symptoms. The utility of provocative tests and the use of HRM in the evaluation of rumination syndrome and post-surgical patients will also be discussed. We believe that characterization of the manometric findings in these areas will eventually lead to incorporation of new criteria into the existing classification.