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![Esophagogastric junction (EGJ) outflow obstruction is characterized by failed or incomplete opening of the EGJ (integrated relaxation or residual pressure [IRP] greater than normal), some peristalsis in the smooth muscle esophagus and pressurization of the swallowed bolus between an unyielding EGJ and peristaltic contraction (arrowhead). Peristalsis can be normal, weak, hypertensive or hypercontractile. UES, upper esophageal sphincter.](profile/Jeffrey-Conklin/publication/250926281/figure/fig6/AS:202691012763664@1425336711685/Esophagogastric-junction-EGJ-outflow-obstruction-is-characterized-by-failed-or.png)
Esophagogastric junction (EGJ) outflow obstruction is characterized by failed or incomplete opening of the EGJ (integrated relaxation or residual pressure [IRP] greater than normal), some peristalsis in the smooth muscle esophagus and pressurization of the swallowed bolus between an unyielding EGJ and peristaltic contraction (arrowhead). Peristalsis can be normal, weak, hypertensive or hypercontractile. UES, upper esophageal sphincter.
Source publication
For several decades esophageal manometry has been the test of choice to evaluate disorders of esophageal motor function. The recent introduction of high-resolution manometry for the study of esophageal motor function simplified performance of esophageal manometry, and revealed previously unidentified patterns of normal and abnormal esophageal motor...
Contexts in source publication
Context 1
... as emptying of the phrenic ampulla. The CFV is obtained by calculating velocity from a best linear fit along the 30 mmHg isobaric contour line at the leading edge of the peristaltic pressure wave from transition zone to CDP (Fig. 4). The CFV can appear rapid when the bolus is pressurized between an unyielding EGJ and a peristaltic con- traction (Fig. 6). This situation might be mistaken by automated analysis software as a simultaneous contraction. The circumstance can be remedied by choosing an isobaric contour pressure that ex- ceeds pressure at the EGJ. The normal CFV does not exceed 9 ...Context 2
... third step in analyzing the EPT according the Chicago classification is to determine if there is a pressurization pattern, which can be useful in understanding the pathogenesis of some Journal of Neurogastroenterology and Motility an esophageal contraction and a mechanical or functional ob- struction, usually at the EGJ (Fig. 6). This pattern is seen with esophageal strictures or neoplasms, Nissen fundoplications and lap bands, and is sometimes a variant of achalasia. Panesophageal pressurization; that is, an isobaric pressure that spans from the UES to EGJ, is one of the common features of achalasia. Its presence defines type II achalasia (Fig. ...Context 3
... by failed or incomplete opening of the EGJ, some peri- stalsis in the smooth muscle esophagus and pressurization of the swallowed bolus between the unyielding EGJ and peristaltic con- traction (Fig. 6). 27,28 Peristalsis can be normal, weak, hyper- tensive or hypercontractile. Mechanical barriers (e.g., strictures, neoplasms, tight fundoplications or tight lap bands), can cause outflow obstruction so this pattern should trigger an evaluation with endoscopy and perhaps endoscopic ultrasound. When no mechanical obstruction is found, ...Similar publications
The introduction of high-resolution esophageal manometry allowed physicians to identify both previously unidentified normal esophageal functions and patterns and various abnormalities. The creation of new charts of pressure patterns and the topography of esophageal pressure has led to the development of new tools for analysis and classification of...
Citations
... Differences between IRP values (supine vs. sitting and supine vs. swallows with solid consistencies) were analyzed using Bland-Altman plots and Lin's coefficient of correlation-concordance (CCC). [15][16][17] Statistical analysis was performed with the statistical package STATA 16.0 (College Station, Texas 77845, USA). ...
SUMMARY.
ThereislittleinformationonthedegreeofconcordancebetweentheresultsobtainedusingtheChicago3.0(CCv3.0)andChicago4.0(CCv4.0)protocolstointerprethigh-resolutionmanometry(HRM)seekingtodeterminethevalueprovidedbythenewswallowingmaneuversincludedinthelastprotocol.Thisisastudyofdiagnostictests,evaluatingconcordancebyconsistencybetweentheresultsobtainedbytheCCv3.0andCCv4.0protocols,inpatientsundergoingHRM.Concordancewasassessedwiththekappatest.Bland–Altmanscatterplots,andLin’scorrelation-concordancecoefficient(CCC)wereusedtoassesstheagreementbetweenIRPmeasuredwithswallowsinthesupineandseatedpositionorwithsolidswallows.Onehundredthirty-twopatientswereincluded(65%women,age53±17years).ThemostfrequentHRMindicationwasdysphagia(46.1%).TypeIwasthemostcommontypeofgastroesophagealjunction.ThemostfrequentCCv4.0diagnoseswerenormalesophagealmotility(68.9%),achalasia(15.5%),andineffectiveesophagealmotility(IEM;5.3%).Theagreementbetweentheresultswassubstantial(Kappa0.77±0.05),withatotalagreementof87.9%.Diagnosticreclassificationoccurredin12.1%,fromIEMinCCv3.0tonormalesophagealmotilityinCCv4.0.Similarly,therewasahighlevelofagreementbetweentheIRPmeasuredinthesupinecomparedtotheseatedposition(CCC0.92)andwithsolidswallows(CCC0.96).Inconclusion,theCCv4.0protocolpresentsahighconcordancecomparedtoCCv3.0.Inthemajorityofmanometricdiagnosesthereisnoreclassificationofpatientswithprovocationtests.However,themorerestrictivecriteriaofCCv4.0achieveabetterreclassificationofpatientswithIEM.
... Esophageal contraction waves following swallowing can be viewed simply as triangular waves [30]. In biomedicine, esophageal peristalsis generates peristaltic wave loads of up to 9.8 kPa [31]. After implantation into the lumen of the esophagus, the stent is subjected to esophageal peristaltic waves and the stent is in a cyclic pulsatile load operating state. ...
Esophageal disease is a common disorder of the digestive system that can severely affect the quality of life and prognosis of patients. Esophageal stenting is an effective treatment that has been widely used in clinical practice. However, esophageal stents of different types and parameters have varying adaptability and effectiveness for patients, and they need to be individually selected according to the patient’s specific situation. The purpose of this study was to provide a reference for clinical doctors to choose suitable esophageal stents. We used 3D printing technology to fabricate esophageal stents with different ratios of thermoplastic polyurethane (TPU)/(Poly-ε-caprolactone) PCL polymer, and established an artificial neural network model that could predict the radial force of esophageal stents based on the content of TPU, PCL and print parameter. We selected three optimal ratios for mechanical performance tests and evaluated the biomechanical effects of different ratios of stents on esophageal implantation, swallowing, and stent migration processes through finite element numerical simulation and in vitro simulation tests. The results showed that different ratios of polymer stents had different mechanical properties, affecting the effectiveness of stent expansion treatment and the possibility of postoperative complications of stent implantation.
... FEES or fluoroscopy is optimal to assess oropharyngeal dysphagia, but high-resolution manometry (HRM) is preferred to evaluate esophageal motility in humans (222). Esophageal manometry measures esophageal pressure profiles using an intraesophageal catheter lined with pressure sensors (223). ...
... Motility disorders can be classified into disorders of EGJ outflow including esophageal achalasia (type I, II, or III) and EGJ outflow obstruction or disorders of peristalsis such as absent contractility, distal esophageal spasm, hypercontractile esophagus, and ineffective esophageal motility (91,226). The key metrics analyzed with HRM are integrated relaxation pressure (IRP), distal contractile integral (DCI), and distal latency ( Figure 9A) (222) to assess LES relaxation, strength of esophageal peristalsis, and latency of deglutitive inhibition, respectively, which help characterize the type of major or minor motility disorder. For example, an elevated IRP denotes an esophageal outflow obstruction or esophageal achalasia ( Figure 9B) (222). ...
... The key metrics analyzed with HRM are integrated relaxation pressure (IRP), distal contractile integral (DCI), and distal latency ( Figure 9A) (222) to assess LES relaxation, strength of esophageal peristalsis, and latency of deglutitive inhibition, respectively, which help characterize the type of major or minor motility disorder. For example, an elevated IRP denotes an esophageal outflow obstruction or esophageal achalasia ( Figure 9B) (222). An increased DCI is supportive of a hypercontractile disorder such as jackhammer esophagus (hypercontractile esophagus). ...
Swallowing impairment is a highly prevalent and clinically significant problem affecting people and dogs. There are myriad causes of swallowing impairment of which gastroesophageal reflux is the most common in both species. Similarities in anatomy and physiology between humans and canines results in analogous swallowing disorders including cricopharyngeus muscle achalasia, esophageal achalasia, hiatal herniation, and gastroesophageal reflux with secondary esophagitis and esophageal dysmotility. Accordingly, the diagnostic approach to human and canine patients with swallowing impairment is similar. Diagnostic procedures such as swallowing fluoroscopy, high-resolution manometry, pH/impedance monitoring, and endolumenal functional luminal imaging probe can be performed in both species; however, nasofacial conformation, increased esophageal length, and the difficulty of completing several of these procedures in awake dogs are inherent challenges that need to be considered. Human patients can convey their symptoms and respond to verbal cues, whereas veterinarians must rely on clinical histories narrated by pet owners followed by comprehensive physical examination and observation of the animal eating different food consistencies and drinking water. Dogs may also be unwilling to drink or eat in the hospital setting and may be resistant to physical restraint during diagnostic procedures. Despite the species differences and diagnostic challenges, dogs are a natural animal model for many oropharyngeal and esophageal disorders affecting people, which presents a tremendous opportunity for shared learnings. This manuscript reviews the comparative aspects of esophageal anatomy and physiology between humans and canines, summarizes the diagnostic assessment of swallowing impairment in both species, and discusses future considerations for collaborative medicine and translational research.
... 95 Correct catheter placement can be ascertained by visualization of both UES and EGJ on the EPT plot and further confirmed by recognizing the pressure inversion point (the point at which the inspiration-associated negative intrathoracic pressure inverts to positive intra-abdominal pressure). 95,96 After appropriate positioning of the catheter and an acclimatization period of 5 minutes, 10 liquid swallows of 5 mL each are given 30 seconds apart with the patient in supine position. Normal saline solution is preferred over water for liquid swallows because it has standard ionic concentration and provides more predictable impedance changes. ...
Background and Aims
Esophageal function testing is an integral component of the evaluation of refractory GERD and esophageal motility disorders. This review summarizes the current technologies available for esophageal function testing, including the functional luminal imaging probe (FLIP), high-resolution esophageal manometry (HRM), and multichannel intraluminal impedance (MII) and pH monitoring.
Methods
We performed a MEDLINE, PubMed, and MAUDE database literature search to identify pertinent clinical studies through March 2021 using the following key words: esophageal manometry, HRM, esophageal impedance, FLIP, MII, and esophageal pH testing. Technical data were gathered from traditional and web-based publications, proprietary publications, and informal communications with pertinent vendors. The report was drafted, reviewed, and edited by the American Society for Gastrointestinal Endoscopy Technology Committee and approved by the Governing Board of the American Society for Gastrointestinal Endoscopy.
Results
FLIP is a high-resolution impedance planimetry system used for pressure and dimension measurement in the esophagus, pylorus, and anal sphincter. FLIP provides complementary information to HRM for esophageal motility disorders, especially achalasia. The Chicago classification, based on HRM data, is a widely adopted algorithmic scheme used to diagnose esophageal motility disorders. MII detects intraluminal bolus movement and, combined with pH measurement or manometry, provides information on acid and non-acid gastroesophageal reflux and bolus transit in patients with refractory GERD and for preoperative evaluation for anti-reflux procedures.
Conclusions
Esophageal function testing techniques (FLIP, HRM, and MII-pH) have diagnostic and prognostic value in the evaluation of esophageal motility disorders and refractory GERD. Newer technologies and classification systems have enabled an increased understanding of these diseases.
... Indications for performing the test include non-obstructive dysphagia, peristaltic reserve prior to anti-reflux surgery, symptoms of regurgitation, and noncardiac chest pain [4]. The first conventional manometry system was developed by Wyle Jerry Dodds and Ron Arndorfer in 1970 [5], which has been state of the art for two decades till 1990. In 1990 Ray Clouse and his colleagues invented the HRM, which had revolutionized the clinical evaluation of esophageal motility disorders. ...
... Typically, 3-5 sensors wide apart [5] Closely placed pressure sensors up to 36 in number 1 cm apart [5] Low fidelity [5] High fidelity [5] Takes more time than HRM average time of 24.4 minutes [6,7] Quick and easy placement of catheter average time of 8.2 minutes [6,7] Need to reposition the catheter (pull through technique) [6] No need for repositioning [6] Uses water perfused catheters which are stiffer and more uncomfortable Uses solid catheters which are softer and more comfortable Unidirectional conventional line plot on the monitor [8,9] Seamless and dynamic spatiotemporal EPT plots by advanced software algorithms [8,9] Wave forms only [5] Color contour [5] HRM with EPT is a new technique that facilitates more accurate measurement of pressure changes in the esophagus by using a specialized catheter with very closely placed pressure censors 1 cm apart along the length of the catheter. The patient is asked to fast for at least 6 hours before the procedure and avoid medications that can alter esophageal motility on the day of the examination like calcium channel blockers, nitrates, prokinetics, loperamide, betareceptor antagonists, opiates, and anticholinergics [10]. ...
... Typically, 3-5 sensors wide apart [5] Closely placed pressure sensors up to 36 in number 1 cm apart [5] Low fidelity [5] High fidelity [5] Takes more time than HRM average time of 24.4 minutes [6,7] Quick and easy placement of catheter average time of 8.2 minutes [6,7] Need to reposition the catheter (pull through technique) [6] No need for repositioning [6] Uses water perfused catheters which are stiffer and more uncomfortable Uses solid catheters which are softer and more comfortable Unidirectional conventional line plot on the monitor [8,9] Seamless and dynamic spatiotemporal EPT plots by advanced software algorithms [8,9] Wave forms only [5] Color contour [5] HRM with EPT is a new technique that facilitates more accurate measurement of pressure changes in the esophagus by using a specialized catheter with very closely placed pressure censors 1 cm apart along the length of the catheter. The patient is asked to fast for at least 6 hours before the procedure and avoid medications that can alter esophageal motility on the day of the examination like calcium channel blockers, nitrates, prokinetics, loperamide, betareceptor antagonists, opiates, and anticholinergics [10]. ...
High-resolution esophageal manometry (HRM) has become the gold standard to diagnose esophageal motility disorders. Usually, this procedure is performed by introducing the catheter, which has pressure sensors, into the esophagus and proximal stomach via the nares. Repeated coiling of the catheter and inability to pass through the gastroesophageal junction (GEJ) are common challenges encountered. Endoscopy-guided placement of the catheter can overcome these difficulties. However, sometimes even with the use of endoscopy, it is difficult to advance catheter due to anatomical variants. The extreme fragility of the catheter and sensors and the high cost of this reusable device precludes the use of biopsy forceps or snare to advance the catheter. There is no literature on using accessories during endoscopy in case of difficult placement under direct visualization. We report a unique case of using Roth Net via the suction channel to advance esophageal manometry catheter into the stomach by using endoscopy.
... According to Pandolfino et al. [18], the pressure morphology of the EGJ was classified in three types, based on the presence of axial cranial separation between LES and crural diaphragm (CD): EGJ Type I, no separation between LES and CD; EGJ Type II, minimal separation (> 1 and ≤ 2 cm); EGJ Type III, > 2 cm of separation. EGJ Type III morphology is suggestive of the presence of a sliding HH [19]. HRM preoperative findings were not revealed to the surgeon who operated blindedly. ...
Background
Hiatal hernia (HH) is common in obese patients undergoing bariatric surgery. Preoperative traditional techniques such as upper gastrointestinal endoscopy (UGIE) or barium swallow/esophagram do not always correlate with intraoperative findings. High-resolution manometry (HRM) has shown a higher sensitivity and specificity than traditional techniques in non-obese patients in the HH diagnosis, whereas there is a lack of data in the morbidly obese population. We aimed to prospectively assess the diagnostic accuracy of HRM in HH detection, in comparison with barium swallow and UGIE, assuming intraoperative diagnosis as a standard of reference.
Methods
Forty-one consecutive morbidly obese patients prospectively recruited from a tertiary-care referral hospital devoted to bariatric and metabolic surgery underwent a preoperative evaluation including standardized GERD questionnaires, barium swallow, UGIE, and HRM. The surgical procedures were performed by a single surgeon who was blinded to the results of other investigations.
Results
HH was intraoperatively diagnosed in 11/41 patients (26.8%). In 10/11 patients, the preoperative HRM showed an esophagogastric junction suggestive of HH. When compared to intraoperative evaluation, the sensitivity of the HRM was 90.9% and the specificity 63.3%, with a positive predictive value of 47.6% and a negative predictive value of 95.0%. HRM showed a higher sensitivity and specificity compared to barium swallow and UGIE.
Conclusions
HRM has a high accuracy of HH detection in morbidly obese patients assuming an intraoperative diagnosis as reference standard. It could therefore be a very useful tool in the preoperative work-up of obese patients undergoing bariatric surgery.
... In esophageal high-resolution manometry, topographical maps are used to calculate an index of motility called the distal contractile integral (DCI) (17,26,37). The DCI assesses the vigor with which a contraction occurs, and it is measured by multiplication of the amplitude, length, and duration of the pressure wave (mmHg·cm·s) (28,32,36). ...
Characterization of High-Amplitude Propagating Pressure Waves (HAPWs or HAPCs) plays a key role in diagnosis of colon dysmotility using any type of colonic manometry. With the introduction of high-resolution manometry, more insight is gained into this most prominent propulsive motor pattern. Here we employ a water-perfused catheter with 84 sensors with intervals between measuring points of 1 cm throughout the colon, for 6-8 hours, in 19 healthy subjects. The catheter contained a balloon to evoke distention. We explored as stimuli a meal, balloon distention, oral prucalopride, and bisacodyl, with a goal to optimally evoke HAPWs. We developed a quantitative measure of HAPW activity, the "HAPW-Index". Our protocol elicited 290 HAPWs. 21% of HAPWs were confined to the proximal colon with an average amplitude of 75.3 ± 3.3 mmHg and an average HAPW-index of 440 ± 58 mmHg.m.s. 29% of HAPWs started in the proximal colon and ended in the transverse or descending colon with an average amplitude of 87.9 ± 3.1 mmHg and an average HAPW-index of 3344 ± 356 mmHg.m.s. 49% of HAPWs started and ended in the transverse or descending colon with an average amplitude of 109.3 ± 3.3 mmHg and an average HAPW-index of 2071 ± 195. HAPWs with and without SPWs initiated the colo-anal reflex, often abolishing 100% of anal sphincter pressure. Rectal bisacodyl and proximal balloon distention were the most optimal stimuli to evoke HAPWs. These measures now allow for a confident diagnosis of abnormal motility in patients with colonic motor dysfunction.
... Se han definido 3 subtipos de acalasia, con distintas implicaciones pronósticas y terapéuticas 4,5 . La acalasia tipo 1 se define como un IRP mayor a 15mmHg y 100% peristalsis fallida. ...
... En la década de 1990, Ray Clouse y sus colegas dieron nacimiento a la manometría de alta resolución al disminuir el espacio entre los sensores ubicados a lo largo del catéter de presión de la manometría convencional de 5 cm a 1 cm, aumentando el número de sensores 36 en total, los cuales se encuentran a una distancia entre ellos menor de 2 cm (5,34). Esto permite evaluar la presión intraluminal a través de toda la extensión del esófago y en los esfínteres (Figura 2) 1 . ...
Antecedentes:
La acalasia es de etiología desconocida y se ha asociado a progresión desde inflamación crónica (acalasia tipo III) hasta pérdida neuronal (acalasia tipo I y II); culminando en aganglionosis y fibrosis con deformación esofágica secundarias (acalasia terminal, esófago sigmoideo) en 5% de casos. Sin embargo, las descripciones morfológicas de la enfermedad son limitadas y los datos existentes hasta hace algunos años se obtuvieron de especímenes de esofagectomía y posteriormente de pacientes sometidos a cirugía.
Objetivo:
Determinar si existe relación entre el estadio y los hallazgos histopatológicos en pacientes con acalasia tratados por miotomía peroral endoscópica.
Material y métodos:
Cohorte prospectivo. Se incluyeron pacientes mayores de edad con acalasia, sin tratamiento endoscópico o quirúrgico previos, a quienes se les realizó biopsia de unión esófago-gástrica durante la miotomía endoscópica de enero 2017 a enero 2020. No se incluyeron pacientes con otro trastorno motor o miopatía, pseudoacalasia, embarazadas y se eliminaron a quienes no fue posible realizar el procedimiento o la biopsia. Tamaño de muestra calculada a conveniencia (baja incidencia). Se realizaron pruebas de normalidad. Las variables cuantitativas se describen con medidas de tendencia central, se utilizó prueba de F, Chi2 y ANOVA para evaluar diferencia entre grupos. Se consideró significativo p ≤0.05. Se utilizaron Excel 2016 y SPSS versión 22.
Resultados:
n= 38 (23 hombres), acalasia tipo I n=6, tipo II n=28 y tipo III n=4; esófago recto n= 32, sigmoideo n= 6. El hallazgo histopatológico vs estadio de acalasia: más frecuente agangliosis (porción esofágica: recto n=26 (81.25%) vs. sigmoideo n=6 (100%), p = 0.84, porción unión esófago-gástrica: recto n= 29 (90.62%) vs. sigmoideo n= 6 (100%), p= 0.22 y porción gástrica: recto n= 30 (93.75%) vs. sigmoideo n= 6 (100%), p= 0.68). Hallazgos histopatológicos vs tipo de acalasia: más frecuente agangliosis (porción esofágica: Tipo I n= 6 (100%) vs. tipo II 27 (96.4%) vs. tipo III n=4 (100%), p= 0.83), porción de unión esófago-gástrica: Tipo I n=5 (83.3%) vs. Tipo II n= 27 (96.4%) vs. tipo III n=4 (100%), p= 0.22) y porción gástrica: Tipo I n= 6 (100%) vs Tipo II n= 29 (92.8%) vs Tipo III n= 4 (100%), p=0.68). Características basales vs. estadio: menor presión basal del EII con esófago sigmoideo (esófago recto 37.2 ± 12.5 mmHg vs esófago sigmoideo 21.0 ± 6.32 mmHg, p= 0.004). Características basales vs tipo de acalasia: IRP menor (Tipo I 20.21 ± 8.48 vs. Tipo II 34.65 ± 10.94 vs. Tipo III 31.65 ± 8.37, p= 0.01) y diámetro esofágico menor en acalasia tipo 1 (Tipo I 3.16 ± 1.50cm vs. Tipo II 4.24 ± 1.19cm vs. Tipo III 3.8 ± 0.81cm, p= 0.02).
Conclusiones:
Los pacientes con acalasia tienen amplio espectro de cambios histopatológicos (agangliosis, fibrosis, grados variables de inflamación) en la capa muscular de la unión esófago-gástrica; no obstante, no existe relación entre estos hallazgos, el estadio ni el tipo de acalasia.
... These results could suggest that either AN can overlap with esophageal dysfunction or esophageal dysfunction can mimic AN symptoms [44]. To date, there are not available data about novel technologies, such as High Resolution Manometry (HRM), that possibly allow a different diagnosis on the basis of the new Chicago Classification [47] in these patients. It has been suggested that self-induced vomiting in patients with purging type AN could potentially cause esophageal acidic damage similar to that occurring in gastroesophageal reflux disease (GERD), increasing the risk of developing sequelae such as Barrett's esophagus [48] and adenocarcinoma. ...
Eating disorders (ED) are frequently associated with a wide range of psychiatric or somatic comorbidities. The most relevant ED are anorexia nervosa (AN), bulimia nervosa (BN), and binge eating disorders (BED). Patients with ED exhibit both upper and lower gastrointestinal (GI) symptoms. Evidence of alterations throughout the GI tract in ED will be analyzed given the role of the GI tract in food intake and its regulation. It remains a matter of debate whether GI disorders are inherent manifestations of ED or the results of malnutrition occurring from ED. Moreover, recent clinical studies have highlighted the growing role of intestinal microbiota in the pathogenesis of ED, making it possible to hypothesize a modulation of intestinal microbiota as a co-adjuvant to standard therapy. The aim of this review is to analyze the link between ED and GI diseases and to present, where known, the potential key factors underlying these conditions. Conclusions: The presence of GI disorders should be investigated in patients with ED. Screening for ED should also be encouraged in individuals seeking treatment for unexplained GI complaints to better address therapeutic issues that surround these difficult medical conditions.
... Achalasia is a primary esophageal motility disorder characterized by the absence of effective peristalsis and inadequate relaxation of the lower esophageal sphincter (LES), resulting in esophageal outflow obstruction (19)(20). The IRP is a critical and robust metric for quantifying swallow induced LES relaxation (18,22), with a primary role in the diagnosis of achalasia and esophageal outflow obstruction (10). Recently, Salvador et al. (23) reported that an increased preoperative IRP correlated directly with LES function and severe dysphagia and was restored to normal by Heller myotomy. ...
