Esophageal solid bolus transit: studies using concurrent videofluoroscopy and manometry

Solid bolus swallows during high-resolution manometry complement multiple rapid swallows in predicting symptoms following antireflux surgery

BACKGROUND

Solid bolus swallows (SBS) assess esophageal peristalsis on high-resolution manometry (HRM). It remains unknown if increase in contraction vigor (contraction reserve) following SBS (SBS-CR) provides information similar to that observed following multiple rapid swallows (MRS-CR).

METHODS

Clinical and HRM data from adult patients (n = 96, age 58.2 years, 61.5% female) undergoing esophageal testing prior to anti-reflux surgery (ARS) were analyzed if both MRS and SBS were available, and compared to similar data from healthy asymptomatic volunteers (n = 18, age 27.5 years, 55.6% female). Patients reported esophageal symptoms before and after ARS using 5-point Likert scales evaluating symptom frequency and severity; scores for each patient were averaged to determine global symptoms. Distal contractile integral (DCI) from single swallows was compared to MRS DCI and SBS DCI; the ratio of single swallow DCI to MRS DCI or SBS DCI ≥1 determined the presence of contraction reserve.

KEY RESULTS

Multiple rapid swallows CR was concordant with SBS CR in 55.6% of healthy volunteers, 100% of absent contractility, 100% of ineffective esophageal motility (IEM) and 56.9% without IEM. Correlation between MRS DCI and SBS DCI was highest when IEM criteria were met (Spearman's rho 0.998). While neither MRS CR nor SBS CR presence differed by presenting symptoms or global symptom score at baseline, post-ARS global symptom burden was highest in the absence of both MRS CR and SBS CR, especially in patients with esophageal hypomotility using Chicago Classification version 4.0 criteria (p = 0.03).

CONCLUSIONS & INFERENCES

Multiple rapid swallows and SBS are complementary in predicting post-ARS symptom burden.

Pharyngeal swallowing and oesophageal motility during a solid meal test: a prospective study in healthy volunteers and patients with major motility disorders

BACKGROUND

The factors that determine how people eat when they are healthy or have disease have not been defined. We used high resolution manometry (HRM) to assess pharyngeal swallowing and oesophageal motility during ingestion of a solid test meal (STM) in healthy volunteers and patients with motility disorders.

METHODS

This study was based at University Hospital Zurich (Zürich, Switzerland). Healthy volunteers who responded to an advertisement completed HRM with ten single water swallows (SWS) in recumbent and upright positions followed by a 200 g rice STM in the upright position. Healthy volunteers were stratified for age and sex to ensure a representative population. For comparison, consecutive patients with major motility disorders on SWS and patients with dysphagia but no major motility disorders on SWS (disease controls) were selected from a database that was assembled prospectively; the rice meal data were analysed retrospectively. During STM, pharyngeal swallows were timed and oesophageal contractions were classified as representing normal motility or different types of abnormal motility in accordance with established metrics. Factors that could potentially be associated with eating speed were investigated, including age, sex, body-mass index, and presence of motility disorder. We compared diagnoses based on SWS findings, assessed with the Chicago Classification v3.0, with those based on STM findings, assessed with the Chicago Classification adapted for solids. These studies are registered with ClinicalTrials.gov, numbers NCT02407938 and NCT02397616.

FINDINGS

Between April 2, 2014, and May 13, 2015, 72 healthy volunteers were recruited and underwent HRM. Additionally, we analysed data from 54 consecutive patients with major motility disorders and 53 with dysphagia but no major motility disorders recruited between April 2, 2013, and Dec 18, 2014. We found important variations in oesophageal motility and eating speed during meal ingestion in healthy volunteers and patients. Increased time between swallows was accompanied by more effective oesophageal contractions (in healthy volunteers, 20/389 [5%] effective swallows at <4 s between swallows vs 586/900 [65%] effective swallows at >11 s between swallows, p<0·0001). Obstructive, spastic, or hypercontractile swallows were rare in healthy volunteers (total <1%). Patients with motility disorders ate slower than healthy volunteers (14·95 g [IQR 11-25] per min vs 32·9 g [25-40] per min, p<0·0001) and pathological oesophageal motility were reproduced when patients consumed the STM. In healthy volunteers, eating speed was associated only with frequency of swallows (slope 2·5 g per min per pharyngeal swallow per min [95% CI 1·1-4·0], p=0·0009), whereas in patients with dysphagia, it was correlated with frequency of effective oesophageal contractions (6·4 g per min per effective contraction per min [4·3-8·5], p<0·0001). Diagnostic agreement was good between the HRM with SWS and rice STM (intra-class correlation coefficient r=0·81, 95% CI 0·74-0·87, p<0·0001).

INTERPRETATION

Our results show normative values for pharyngeal swallowing and oesophageal motility in healthy volunteers. Detailed analysis of HRM data acquired during an STM shows that the rate-limiting factor for intake of solids in health is the frequency of pharyngeal swallowing and not oesophageal contractility. The reverse is true in patients with oesophageal motility disorders, in whom the frequency of effective oesophageal contractions determines eating speed.

FUNDING

University Hospital Zurich.

High-resolution manometric evaluation of the effects of cisapride on the esophagus during administration of solid and liquid boluses in awake healthy dogs

OBJECTIVE To validate the use of high-resolution manometry (HRM) in awake, healthy dogs and compare the effects of bolus type (liquid vs solid) and drug treatment (saline [0.9% NaCl] solution [SS] vs cisapride) on esophageal pressure profiles. ANIMALS 8 healthy dogs. PROCEDURES In a crossover study, each dog received SS (10 mL) IV, and HRM was performed during oral administration of 10 boluses (5 mL each) of water or 10 boluses (5 g each) of canned food. Cisapride (1 mg/kg in 60 mL of SS) was subsequently administered IV to 7 dogs; HRM and bolus administration procedures were repeated. Two to 4 weeks later, HRM was repeated following administration of SS and water and food boluses in 4 dogs. Pressure profile data were obtained for all swallows, and 11 outcome variables were statistically analyzed. RESULTS After SS administration, predicted means for the esophageal contractile integral were 850.4 cm/mm Hg/s for food boluses and 660.3 cm/mm Hg/s for water boluses. Predicted means for esophageal contraction front velocity were 6.2 cm/s for water boluses and 5.6 cm/s for food boluses after SS administration. Predicted means for residual LES pressure were significantly higher following cisapride administration. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that HRM was feasible and repeatable in awake healthy dogs of various breeds and sizes. Stronger esophageal contractions and faster esophageal contraction velocity occurred during solid bolus and liquid bolus swallows, respectively. Lower esophageal sphincter pressure increased significantly following cisapride administration. Esophageal contractions and bolus transit latency should be further evaluated by HRM in clinically dysphagic dogs.

Can mastication in children with cerebral palsy be analyzed by clinical observation, dynamic ultrasound and 3D kinematics?

The aim of this study was to explore the feasibility of the Mastication Observation and Evaluation (MOE) instrument, dynamic ultrasound and 3D kinematic measurements to describe mastication in children with spastic cerebral palsy and typically developing children. Masticatory movements during five trials of eating a biscuit were assessed in 8 children with cerebral palsy, spastic type (mean age 9.08years) and 14 typically developing children (mean age 9.01years). Differences between trials were tested (t-test) and the mastication of individual children with cerebral palsy was analyzed. MOE scores ranged from 17 to 31 (median 24) for the children with cerebral palsy and from 28 to 32 (median 31) for the typically developing children. There was an increased chewing cycle duration, a smaller left-right and up-down tongue displacement and larger anterior mandible movements for the trials (n=40) of cerebral palsy children (p<0.000 for all comparisons) compared to the trials of typically developing children (n=70). The MOE captures differences in mastication between individual children with cerebral palsy. The MOE items 'jaw movement' and 'fluency and coordination' showed the most similarity with the objective measurements. Objective measurements of dynamic ultrasound and 3D kinematics complemented data from the MOE instrument.

Subclinical dysphagia in persons with Prader-Willi syndrome

Prader-Willi Syndrome (PWS) is caused by a genetic imprinting abnormality resulting from the lack of expression of the paternal genes at 15q11-q13. Intellectual disability, low muscle tone, and life-threatening hyperphagia are hallmarks of the phenotype. The need for the Heimlich maneuver, death from choking, and pulmonary infection occur in a disproportionally high number of persons with PWS. The widely held belief is that eating behaviors are responsible for choking and aspiration; yet, no investigation had sought to determine if swallowing impairments were present in persons with PWS. To address this research and clinical gap, simultaneous videofluoroscopy and nasal respiratory signals were used to record swallowing function and breathing/swallowing coordination in 30 participants with PWS. Subjects consumed thin liquid and barium cookies under two randomized conditions as follows: (i) controlled (cues to swallow and standardized bolus sizes); (ii) spontaneous (no cues or bolus size control). Under videofluoroscopy, the cohort showed disordered pharyngeal and esophageal swallowing in both conditions with disturbances in timing, clearance, and coordination of swallowing with the respiratory cycle. No participant showed a sensory response such as attempting to clear residue or coughing; thereby supporting the lack of overt symptoms. We conclude that the high death rate from choking and pulmonary infection in children and adults with PWS may be related, in part, to underlying, asymptomatic dysphagia. The combination of rapid eating and dysphagia would increase the risk of aspiration-related morbidity and mortality. © 2016 Wiley Periodicals, Inc.

Comparison of videofluoroscopy and impedance planimetry for the evaluation of oesophageal stenosis: a retrospective study

Objectives

To compare videofluoroscopy that included a tablet test with impedance planimetry (EndoFLIP^®) for the evaluation of oesophageal stenosis in patients with dysphagia.

Methods

In 56 patients, videofluoroscopic examinations following the transit of a 14-mm tablet were retrospectively reviewed and correlated with impedance planimetry findings, a catheter-based method using impedance planimetry to display the oesophageal diameter estimates. Additional findings assessed were the occurrence of symptoms during tablet passage and evaluation of oesophageal motility.

Results

Impaction of the tablet occurred in 31/56 patients; nine showed a moderate delay (2–15 s), three a short delay (<2 s) and 13 no delay of tablet passage. Both methods showed a significant correlation between tablet impaction and oesophageal diameter <15.1 mm, as measured by impedance planimetry (p = 0.035). The feeling of the tablet getting stuck was reported by seven patients, six showing impaction of the tablet (four with an EndoFLIP-diameter < 13 mm, two with a diameter of 13–19 mm) and one showing delayed passage (EndoFLIP diameter of 17 mm).

Conclusions

Videofluoroscopy and impedance planimetry correlate significantly regarding tablet impaction and residual oesophageal lumen. A standardized 14-mm tablet is helpful in demonstrating oesophageal strictures in dysphagic patients. Triggering of subjective symptoms provides valuable information during a videofluoroscopic study.

Key Points

• A 14-mm tablet can demonstrate oesophagogastric junction narrowing in patients with dysphagia.

• Type of passage of a tablet enables estimation of oesophageal luminal diameter.

• Videofluoroscopy and impedance planimetry correlate significantly regarding tablet impaction and residual oesophageal lumen.

Functional Esophageal Disorders

Functional esophageal disorders consist of a disease category that present with esophageal symptoms (heartburn, chest pain, dysphagia, globus) not explained by mechanical obstruction (stricture, tumor, eosinophilic esophagitis), major motor disorders (achalasia, EGJ outflow obstruction, absent contractility, distal esophageal spasm, jackhammer esophagus), or gastroesophageal reflux disease (GERD). While mechanisms responsible are unclear, it is theorized that visceral hypersensitivity and hypervigilance play an important role in symptom generation, in the context of normal or borderline function. Treatments directed at improving borderline motor dysfunction or reducing reflux burden to sub-normal levels have limited success in symptom improvement. In contrast, strategies focused on modulating peripheral triggering and central perception are mechanistically viable and clinically meaningful. However, outcome data from these treatment options are limited. Future research needs to focus on understanding mechanisms underlying visceral hypersensitivity and hypervigilance so that appropriate targets and therapies can be developed.

Influence of everyday bolus consistencies in different body positions on high-resolution esophageal pressure topography (HREPT) parameters

The standard protocol for esophageal manometry involves placing the patient in the supine position with head turned to left (supine head left [SHL]) while evaluating liquid bolus swallows. Routinely, semisolid or solid boluses are not evaluated. Currently, the daily American diet includes up to 40% solid or semisolid texture. Thus far, the data on the effect of different bolus on high-resolution esophageal pressure topography (HREPT) parameters are scarce. This study aims to evaluate the effect of every day bolus consistencies in different body positions on HREPT variables. HREPT was performed on healthy volunteers with a modified protocol including liquid swallows in the SHL position followed by applesauce (semisolid), cracker (solid), and marshmallow (soft solid) in three different positions (SHL, sitting, and standing). A total of 38 healthy adult subjects (22 males and 16 females, median age = 27, and mean body mass index = 25) were evaluated. The resting upper esophageal sphincter pressure was significantly different while subjects swallowed crackers, applesauce, and marshmallows in most positions compared with liquid SHL (P < 0.05). The lower esophageal sphincter, contractile front velocity, and distal contractile integral pressures did not differ in all different consistencies compared with SHL. The integrated relaxation period was significantly higher with solid bolus compared with liquid bolus only in SHL position. The intrabolus pressure was significantly different with solid and soft solid boluses in all postures compared to liquid SHL. The American diet consistency affects upper esophageal sphincter pressure and partially integrated relaxation period and intrabolus pressure in various positions. Semisolid bolus swallows do not cause substantial pressure changes and are safe for evaluation and maintaining adequate caloric intake in patients with dysphagia who cannot tolerate solids.

Treatment of esophageal motility disorders based on the chicago classification

OPINION STATEMENT

The Chicago Classification divides esophageal motor disorders based on the recorded value of the integrated relaxation pressure (IRP). The first group includes those with an elevated mean IRP that is associated with peristaltic abnormalities such as achalasia and esophagogastric junction outflow obstruction. The second group includes those with a normal mean IRP that is associated with esophageal hypermotility disorders such as distal esophageal spasm, hypercontractile esophagus (jackhammer esophagus), and hypertensive peristalsis (nutcracker esophagus). The third group includes those with a normal mean IRP that is associated with esophageal hypomotility peristaltic abnormalities such as absent peristalsis, weak peristalsis with small or large breaks, and frequent failed peristalsis. The therapeutic options vary greatly between the different groups of esophageal motor disorders. In achalasia patients, potential treatment strategies comprise medical therapy (calcium channel blockers, nitrates, and phosphodiesterase 5 inhibitors), endoscopic procedures (botulinum toxin A injection, pneumatic dilation, or peroral endoscopic myotomy) or surgery (Heller myotomy). Patients with a normal IRP and esophageal hypermotility disorder are candidates for medical therapy (nitrates, calcium channel blockers, phosphodiesterase 5 inhibitors, cimetropium/ipratropium bromide, proton pump inhibitors, benzodiazepines, tricyclic antidepressants, trazodone, selective serotonin reuptake inhibitors, and serotonin-norepinephrine reuptake inhibitors), endoscopic procedures (botulinum toxin A injection and peroral endoscopic myotomy), or surgery (Heller myotomy). Lastly, in patients with a normal IRP and esophageal hypomotility disorder, treatment is primarily focused on controlling the presence of gastroesophageal reflux with proton pump inhibitors and lifestyle modifications (soft and liquid diet and eating in the upright position) to address patient's dysphagia.

Esophageal motor function: technical aspects of manometry

High-resolution manometry (HRM) has advanced the understanding of esophageal peristaltic mechanisms and has simplified esophageal motor testing. In this article the technical aspects of HRM are addressed, focusing on test protocols, in addition to concerns and pitfalls in performing esophageal motor studies. Specifically, catheter positioning, equipment-related artifacts, basal data acquisition, adequate swallows, and provocative maneuvers are discussed.

Relationship between multiple water swallows and gastroesophageal reflux in patients with normal esophageal motility

Multiple water swallows (MWS) stimulates neural inhibition, resulting in abolition of contractions in the esophageal body and complete lower esophageal sphincter relaxation, which is followed by peristalsis and the lower esophageal sphincter contraction. We assessed the relationship between MWS and gastroesophageal reflux in patients with esophageal symptoms and with normal findings by high-resolution manometry (HRM). We retrospectively reviewed the clinical records of patients who underwent HRM and a 24-hour ambulatory impedance-pH study. Correlation between the findings of the impedance-pH study and abnormal MWS responses without motility disorders was evaluated. Independent t-tests were used for statistical analysis. Of 28 patients, 20 (71%) had abnormal MWS responses: four (20%) had abnormal responses during MWS, six (30%) had abnormal responses after MWS, and 10 (50%) had abnormal responses both during and after MWS. Total acid exposure times were significantly longer in patients with abnormal MWS responses than in patients with normal MWS responses. In particular, upright acid exposure time and all reflux percent times were significantly longer in patients with abnormal MWS responses. However, bolus clearance time and longest reflux episode were not different between the two groups. Abnormal MWS responses predicted increased acid exposure times in patients with normal findings of HRM by the Chicago classification.

Sensation of stasis is poorly correlated with impaired esophageal bolus transport

BACKGROUND

It is common belief that symptoms of patients with non-obstructive dysphagia are the result of impaired bolus clearance in the esophagus, usually caused by esophageal motility disorders. We therefore investigated the relationship between transit of swallowed boluses and the symptom dysphagia.

METHODS

Twenty healthy volunteers and 20 patients with dysphagia underwent videofluoroscopy. Success of bolus transport was graded on a 7-point scale. Each subject swallowed five liquid and five solid barium boluses.

KEY RESULTS

For liquids, patients reported dysphagia during 1 [0-3] of the five swallows, while controls reported no dysphagia (median 0 [0-0]; p = 0.003). For solids, patients reported dysphagia during 3 [2-4] of five swallows, while controls reported dysphagia in 0.5 [0-2] of five swallows (p = 0.001). When correlating dysphagia to ineffective clearance (score ≥ 3), in 3 [2-4] of five liquids, the subjects perception of clearance was related to the clearance result on fluoroscopy in patients and also 3 [1-5] were correctly perceived in controls (p = 0.6). For solids, in 4 [3-5] of five swallows, the subjects perception of clearance was related to the clearance result on fluoroscopy in patients, but only 2 [1-3] of five swallows were correctly perceived by controls, the difference being statistically significant.

CONCLUSIONS & INFERENCES

Patients very frequently report dysphagia when bolus clearance is successful. Therefore, the major underlying problem in patients with non-obstructive dysphagia is disordered perception and increased sensitivity to physiological bolus stasis. Treatment should therefore be directed at reducing increased sensitivity rather than at improving motility.

Esophageal motility in troublesome belching

CONTEXT

Supragastric belches are the main determinants of troublesome belching symptoms. In supragastric belches, air is rapidly brought into the esophagus and is immediately followed by a rapid expulsion before it has reached the stomach.

OBJECTIVE

To evaluate the esophageal contraction and transit after wet swallows in patients with troublesome belching.

METHODS

Esophageal contraction and transit were evaluated in 16 patients with troublesome belching and 15 controls. They were measured at 5, 10, 15, and 20 cm from the lower esophageal sphincter (LES) by a solid state manometric and impedance catheter. Each subject swallowed five 5 mL boluses of saline.

RESULTS

The amplitude, duration and area under the curve of contractions were similar in patients with troublesome belching and control subjects. The total esophageal bolus transit time was 6.2 (1.8) s in patients with troublesome belching and 6.1 (2.3) s in controls (P=0.55). The bolus presence time was longer in controls than in patients at 5 cm from the LES [controls: 6.0 (1.1) s, patients: 4.9 (1.2) s, P=0.04], without differences at 10, 15 and 20 cm from the LES. The bolus head advanced time was longer in patients than controls from 20 cm to 15 cm [controls: 0.1 (0.1) s, patients: 0.7(0.8)s, P=0.01] and from 15 cm to 10 cm [controls: 0.3 (0.1) s, patients: 1.6 (2.6) s, P=0.01] of the LES, without difference from 10 cm to 5 cm [controls: 0.7 (0.3) s, patients: 1.0 (1.1) s, P=0.37]. There was no difference in segment transit time.

CONCLUSION

There was no difference in esophageal contractions between patients with troublesome belching and controls. The swallowed bolus went slower into the proximal and middle esophageal body in patients than in control, but cross the distal esophageal body faster in patients than in controls.

Advances in motility testing--current and novel approaches

Disorders of gastrointestinal motility are frequently seen in clinical practice. Apart from motility disorders, factors leading to lowered visceroperception thresholds are recognized as commonly involved in the pathogenesis of functional gastrointestinal disorders. The wide array of gastrointestinal motility and viscerosensitivity tests available is in contrast with the relatively limited number of tests used universally in clinical practice. The main reason for this discrepancy is that the outcome of a test only becomes truly important when it carries clinical consequences. The main goal of this Review is to assess the place of the presently available gastrointestinal motility and sensitivity tests in the clinical armamentarium of the gastroenterologist.

Evaluation of esophageal motor function in clinical practice

Esophageal motor function is highly coordinated between central and enteric nervous systems and the esophageal musculature, which consists of proximal skeletal and distal smooth muscle in three functional regions, the upper and lower esophageal sphincters, and the esophageal body. While upper endoscopy is useful in evaluating for structural disorders of the esophagus, barium esophagography, radionuclide transit studies, and esophageal intraluminal impedance evaluate esophageal transit and partially assess motor function. However, esophageal manometry is the test of choice for the evaluation of esophageal motor function. In recent years, high-resolution manometry (HRM) has streamlined the process of acquisition and display of esophageal pressure data, while uncovering hitherto unrecognized esophageal physiologic mechanisms and pathophysiologic patterns. New algorithms have been devised for analysis and reporting of esophageal pressure topography from HRM. The clinical value of HRM extends to the pediatric population, and complements preoperative evaluation prior to foregut surgery. Provocative maneuvers during HRM may add to the assessment of esophageal motor function. The addition of impedance to HRM provides bolus transit data, but impact on clinical management remains unclear. Emerging techniques such as 3-D HRM and impedance planimetry show promise in the assessment of esophageal sphincter function and esophageal biomechanics.

Esophageal contractions, bolus transit and perception of transit after swallows of liquid and solid boluses in normal subjects

CONTEXT: Esophageal dysphagia is the sensation that the ingested material has a slow transit or blockage in its normal passage to the stomach. It is not always associated with motility or transit alterations. OBJECTIVES: To evaluate in normal volunteers the possibility of perception of bolus transit through the esophagus after swallows of liquid and solid boluses, the differences in esophageal contraction and transit with these boluses, and the association of transit perception with alteration of esophageal contraction and/or transit. METHODS: The investigation included 11 asymptomatic volunteers, 4 men and 7 women aged 19-58 years. The subjects were evaluated in the sitting position. They performed swallows of the same volume of liquid (isotonic drink) and solid (macaroni) boluses in a random order and in duplicate. After each swallow they were asked about the sensation of bolus passage through the esophagus. Contractions and transit were evaluated simultaneously by solid state manometry and impedance. RESULTS: Perception of bolus transit occurred only with the solid bolus. The amplitude and area under the curve of contractions were higher with swallows of the solid bolus than with swallows of the liquid bolus. The difference was more evident in swallows with no perception of transit (n = 12) than in swallows with perception (n = 10). The total bolus transit time was longer for the solid bolus than for the liquid bolus only with swallows followed by no perception of transit. CONCLUSION: The results suggest that the perception of esophageal transit may be the consequence of inadequate adaptation of esophageal transit and contraction to the characteristics of the swallowed bolus.

Relationship between esophageal contraction patterns and clearance of swallowed liquid and solid boluses in healthy controls and patients with dysphagia

BACKGROUND

Non-obstructive dysphagia patients prove to be a difficult category for clinical management. Esophageal high-resolution manometry (HRM) is a novel method, used to analyze dysphagia. However, it is not yet clear how findings on HRM relate to bolus transport through the esophagus.

METHODS

Twenty healthy volunteers and 20 patients with dysphagia underwent HRM and videofluoroscopy in a supine position. Each subject swallowed five liquid and five solid barium boluses. Esophageal contraction parameters and bolus transport were evaluated with HRM and concurrent videofluoroscopy.

KEY RESULTS

Stasis of liquid and solid barium boluses occurred in patients and in healthy volunteers in 64% and 41% and in 84% and 82% of the swallows, respectively. Overall, 70% of the liquid and 72% of the solid bolus swallows were followed by a peristaltic contraction, the difference not being statistically significant. Statistically significant associations were found for transition zone length of liquid and solid boluses, and for DCI and distal contraction amplitudes for liquid stasis. No correlation was found between the degree of stasis and other manometric parameters.

CONCLUSIONS & INFERENCES

Stasis of both liquid and solid boluses occurs frequently in patients and in controls and can be regarded as physiological. Motility patterns can predict the effectiveness of bolus transit and level of stasis to some degree but the relationship between esophageal motility and transit is complex and far from perfect. Esophageal manometry is therefore currently deemed unfit to be used for the prediction of bolus transit, and should rather be used for the identification of treatable esophageal motility disorders.

Future directions in esophageal motility and function - new technology and methodology

BACKGROUND

Symptom based diagnosis is not reliable in patients with swallowing problems, heartburn, and other dyspeptic complaints. The aim of investigation is to provide clinically relevant measurements of gastrointestinal structure and function that explain the cause of symptoms, identify pathology, and guide effective management. Current practice rarely meets these ideals.

PURPOSE

This review considers recent advances in technology such as high-resolution manometry (HRM) with esophageal pressure topography (EPT), HRM with impedance, high frequency ultrasound, and endoscopic functional luminal impedance planimetry (Endo-FLIP) that provide new opportunities to identify the pathophysiologic basis of esophageal symptoms and disease. As experience with these new devices increases researchers are developing new methodologies that maximize their utility in clinical practice. For example, application of HRM to assess motility and function during and after a test meal can identify the causes of swallowing problems, reflux and other postprandial symptoms and intra-operative application of Endo-FLIP may help surgeons perform antireflux surgery. These examples illustrate the potential of physiologic measurement to direct rational and effective clinical management for individual patients.

Weak and absent peristalsis

BACKGROUND

Weak and absent esophageal peristalsis are frequently encountered esophageal motility disorders, which may be associated with dysphagia and which may contribute to gastroesophageal reflux disease. Recently, rapid developments in the diagnostic armamentarium have taken place, in particular, in high-resolution manometry with or without concurrent intraluminal impedance monitoring.

PURPOSE

This article aims to review the current insights in the terminology, pathology, pathophysiology, clinical manifestations, diagnostic work-up,and management of weak and absent peristalsis.

High-resolution manometry

The following presents commentaries on the interest of high-resolution manometry for understanding the anatomy and physiology of the esophagogastric junction; the subtypes of achalasia, as diagnosed by high-resolution manometry; the interest of high-resolution manometry in the evaluation of dysphagia following fundoplication; and the appropriate clinical protocol for high-resolution manometry.

Normative values and inter-observer agreement for liquid and solid bolus swallows in upright and supine positions as assessed by esophageal high-resolution manometry

BACKGROUND

High-resolution manometry (HRM) with spatiotemporal representation of pressure data is a recent advance in esophageal measurement. At present, normal values are available for 5mL water swallows in the supine position. This study provides reference values for liquid and solid bolus swallows in the upright seated and supine positions.

METHODS

A total of 23 asymptomatic volunteers (11M:12F, age 20-56) underwent HRM (Manoscan 360; Sierra Scientific Instruments) with 5mL water and 1cm3 bread swallows in the upright and supine positions. Normal values for primary parameters associated with effective bolus transport [proximal transition zone length (PTZ, assesses peristaltic coordination], contraction front velocity (CFV), distal contractile index (DCI) and integrated relaxation pressure (IRP)] are presented. For each parameter, median values along with the 5-95th percentile range are reported. Inter-observer agreement between independent observers is reported using the intra-class correlation coefficient.

KEY RESULTS

A higher proportion of swallows were peristaltic for liquids than solids in both the upright and supine positions (both P<0.05). As workload increases with solid bolus and on moving from the upright to the supine position the esophageal contractile response resulted in a shorter PTZ, a slower CFV, and a more vigorous DCI. Also IRP increased during solid bolus transit (all P<0.01). There was significant agreement between independent observers for HRM parameters.

CONCLUSIONS & INFERENCES

Normative values for esophageal function for solids as well as liquids and in the 'physiologic', upright position will optimize the utility of HRM studies. The high level of inter-observer agreement indicates that these can be applied as reference values in clinical practice.

Failure to respond to physiologic challenge characterizes esophageal motility in erosive gastro-esophageal reflux disease

BACKGROUND

Non-specific esophageal dysmotility with impaired clearance is often present in patients with gastro-esophageal reflux disease (GERD), especially those with erosive disease; however the physio-mechanic basis of esophageal dysfunction is not well defined.

METHODS

Retrospective assessment of patients with erosive reflux disease (ERD; n=20) and endoscopy negative reflux disease (ENRD; n=20) with pathologic acid exposure on pH studies (>4.2% time/24 h) and also healthy controls (n=20) studied by high resolution manometry. Esophageal motility in response to liquid and solid bolus swallows and multiple water swallows (MWS) was analyzed. Peristaltic dysfunction was defined as failed peristalsis, spasm, weak or poorly coordinated esophageal contraction (>3cm break in 30 mmHg isocontour).

KEY RESULTS

Peristaltic dysfunction was present in 33% of water swallows in controls, 56% ENRD and 76% ERD respectively (P<0.023 vs controls, P=0.185 vs ENRD). The proportion of effective peristaltic contractions improved with solid compared to liquid bolus in controls (18%vs 33%, P=0.082) and ENRD (22%vs 54%, P=0.046) but not ERD (62%vs 76%, P=0.438). Similarly, MWS was followed by effective peristalsis in 83% of controls and 70% ENRD but only 30% ERD patients (P<0.017 vs controls and P<0.031 vs ENRD). The association between acid exposure and dysmotility was closer for solid than liquid swallows (r=0.52 vs 0.27).

CONCLUSIONS & INFERENCES

Peristaltic dysfunction is common in GERD. ERD patients are characterized by a failure to respond to the physiologic challenge of solid bolus and MWS that is likely also to impair clearance following reflux events and increase exposure to gastric refluxate.

Apple sauce improves detection of esophageal motor dysfunction during high-resolution manometry evaluation of dysphagia

BACKGROUND

Esophageal manometry utilizes water swallows to evaluate esophageal motor abnormalities in patients with dysphagia, chest pain, or reflux symptoms. Although manometry is the gold standard for evaluation of these symptoms, patients with dysphagia often have normal results in manometry studies.

AIM

The objective of this work was to test the hypothesis that challenging the esophagus with viscous apple sauce boluses uncovers motor abnormalities in patients with dysphagia not seen when using water swallows.

METHODS

High-resolution esophageal manometry was performed using ten water swallows followed by ten apple sauce swallows in consecutive subjects presenting with dysphagia. Subjects with grossly abnormal water swallow evaluations were excluded. Each swallow was categorized as normal, hypotensive (distal isobaric contour plots of < 30 mmHg over >5 cm), or simultaneous (distal esophageal velocity ≥ 8.0 cm/s). Ineffective esophageal motility (IEM) was defined as ≥ 30% hypotensive swallows, and pressurization was defined as ≥ 20% simultaneous pressure waves.

RESULTS

Data from 41 subjects was evaluated. Overall, 96.3% of water swallows were normal, 2.9% hypotensive, and 0.7% simultaneous. Only 70.3% of viscous swallows were normal; 16.7% were hypotensive and 13.0% were simultaneous (P < 0.001 all groups). Seven (17.1%) met criteria for IEM, and pressurization with viscous swallows was observed for nine (22.0%). Fourteen subjects (34.1%) had abnormal results from viscous studies. The presence of any abnormal water swallows was predictive of abnormal viscous swallows (OR = 9.00, CI = 2.15-80.0), although the presence of hypotensive or simultaneous water swallows was not associated with IEM (OR = 0.63, CI = 0.16-2.17) or pressurization (OR = 7.00, CI = 0.90-315.4) with viscous apple sauce.

CONCLUSIONS

Apple sauce challenge increased identification of classifiable motor disorders in patients with dysphagia and may be preferred to alternative bolus materials.

Sensory input pathways and mechanisms in swallowing: a review

Over the past 20 years, research on the physiology of swallowing has confirmed that the oropharyngeal swallowing process can be modulated, both volitionally and in response to different sensory stimuli. In this review we identify what is known regarding the sensory pathways and mechanisms that are now thought to influence swallowing motor control and evoke its response. By synthesizing the current state of research evidence and knowledge, we identify continuing gaps in our knowledge of these mechanisms and pose questions for future research.

Pediatric esophageal high-resolution manometry: utility of a standardized protocol and size-adjusted pressure topography parameters

OBJECTIVES

Esophageal high-resolution manometry (EHRM) has evolved rapidly from a research tool to a routine investigation in adult clinical practice. This study proposes and evaluates a standardized EHRM protocol for use in pediatric clinical practice.

METHODS

Thirty pediatric patients underwent unsedated EHRM. Indications for EHRM were dysphagia, feeding difficulty, or pre-fundoplication assessment. Two 20-channel customized water-perfused silicone catheters, with an outside diameter of 3.8 mm (MuiScientific, Ontario, CA), were used. The catheters had one distal gastric channel, five channels 0.5 cm apart for the e-sleeve, and 14 proximal channels either 1 cm (for children <5 years) or 2 cm apart (for children >5 years). Single wet swallows, multiple rapid swallows (MRS), and solid swallows were systematically studied.

RESULTS

The median age was 10 years (range 6 months-15 years). The esophageal motor findings were normal peristalsis (n=15), peristaltic dysfunction (n=12), achalasia (n=3), and spasm on consumption of solid food (n=2). The distal contractile integral adjusted for esophageal length (DCIa) of patients with peristaltic dysfunction was significantly lower than that of patients without peristaltic dysfunction (P<0.001). On MRS, aperistalsis with lack of esophagogastric junction (EGJ) relaxation was observed in patients with achalasia, and aperistalsis with complete EGJ relaxation was observed in patients with severe peristaltic dysfunction. On consumption of solid food, esophageal spasm associated with bolus impaction was observed in two patients.

CONCLUSIONS

This study provides objective information with regard to topography pressure parameters in esophageal motility disorders of childhood while using a standardized EHRM protocol. The new DCIa variable may be useful for the assessment of patients with peristaltic dysfunction.

Mechanisms of bolus clearance in patients with laparoscopic adjustable gastric bands

BACKGROUND

The components of esophageal function important to success with laparoscopic adjustable gastric banding (LAGB) are not well understood. A pattern of delayed, however, successful bolus transit across the LAGB is observed.

METHODS

Successful LAGB patients underwent a high-resolution video manometry study in which bolus clearance, flow, and intraluminal pressures were recorded. Liquid and semi-solid swallows and stress barium (a combination of semi-solid swallows and liquid barium) were performed. A new measurement, the lower esophageal contractile segment (LECS), was defined and evaluated.

RESULTS

Twenty patients participated (mean age 48.3 +/- 12.0 years, four men, %excess weight loss 65.6 +/- 18.0). During semi-solid swallows, two patterns of esophageal clearance were observed: firstly, a native pattern (n = 10) similar to that which is expected in non-LAGB patients; secondly, a lower esophageal sphincter-dependent pattern (n = 7), where flow only occurred when the intrabolus pressure increased during the lower esophageal sphincter (LES) aftercontraction. In both patterns, if there was incomplete bolus clearance, reflux was observed and was usually followed by another swallow. A mean of 4.5 +/- 2.9 contractions were required to clear the semi-solid bolus. Contractions with an intact LECS demonstrated longer flow duration: 7.1 +/- 3.8 vs.1.6 +/- 3.2 s, p < 0.005. During the stress barium, an intrabolus pressure of 44.5 +/- 16.0 mm Hg leads to cessation of intake.

CONCLUSIONS

In LAGB patients, normal esophageal peristaltic contractions transition to a LES aftercontraction, producing trans-LAGB flow. Repeated contractions are required to clear a semi-solid bolus. Incorporating measurements of the LECS into assessments of esophageal motility in LAGB patients may improve the usefulness of this investigation.

Impact of nadir lower oesophageal sphincter pressure on bolus clearance assessed by combined manometry and multi-channel intra-luminal impedance measurement

This study aimed to assess the relationship between nadir lower oesophageal sphincter pressure (LOSP) and wave amplitude (WA) in oesophageal bolus clearance. Concurrent oesophageal manometry and impedance were performed in 146 subjects [41 healthy, 24 non-obstructive dysphagia (NOD) and 81 gastro-oesophageal reflux (GOR)]. Patients with achalasia and diffuse oesophageal spasm were excluded. Swallow responses were categorized by nadir LOSP. For each category of nadir LOSP, WA at the distal 2 recording sites were grouped into bins of 10 mmHg and the proportion of waves in each bin associated with a normal bolus presence time (BPT) was determined. Nadir LOSP, distal BPT, total bolus transit time and the proportion of impaired oesophageal clearance in patients with NOD were greater than those of healthy subjects and patients with GOR. Overall, responses with impaired oesophageal clearance had significantly lower WA (54 +/- 1 vs 81 +/- 1 mmHg; P < 0.0001) and higher nadir LOSP (2.7 +/- 0.4 vs 1.0 +/- 0.1 mmHg, P < 0.001). For each level of nadir LOSP, there was a direct relationship between distal WA and successful bolus clearance of both liquid and viscous boluses from the distal oesophagus. As nadir LOSP increased, the relationship between WA and bolus clearance shifted to the right and higher amplitudes were required to achieve the same effectiveness of clearance. Hypotensive responses with nadir LOSP > or = 3 mmHg were less likely to clear than those with nadir LOSP < 3 mmHg, for both liquid (7/29 vs 162/276; P < 0.001) or viscous boluses (11/46 vs 176/279; P < 0.0001). Nadir LOSP is an important determinant of bolus clearance from the distal oesophagus, particularly in patients with NOD.

Influence of age on mastication: effects on eating behaviour

The present review covers current knowledge about the ageing of oral physiology related to mastication and its effects on eating behaviour. Mastication is the first process undergone by a food during feeding. It has a key role in the maintenance of nutritional status in two respects. First, the perceptions of food's sensory properties elicited during chewing and swallowing are one of the major determinants of the pleasure which drives us to eat; second, the properties of the swallowed bolus are affected by oral conditions and this may modulate the subsequent phases of digestion. Ageing in healthy dentate subjects induces moderate changes in oral physiology. Changes in neuromuscular activity are partly compensated by changes in chewing behaviour. No clear age effect is seen in texture perception, although this does impact on food bolus properties. In contrast, great alterations in both chewing behaviour and food bolus properties are observed when ageing is associated with a compromised dentition, general health alterations and drug intake. Eating behaviour is far more complex than just chewing behaviour and the concerns of the elderly about food cannot be explained solely by oral physiology. Discrepancies are often noticed with older subjects between various objective measurements of oral performance and corresponding measures of self-perception. In addition, although more foods are recognised as hard to chew with increasing age, there is no clear shift in preference towards food that is easy to chew. Food choices and food consumption are also driven by memory, psychology and economic factors. Advances in the understanding of food choice in the elderly need a sustained collaborative research effort between sensory physiologists, nutritionists, and food scientists.

Multiple rapid swallowing: a complementary test during standard oesophageal manometry

Multiple rapid swallowing (MRS) stimulates neural inhibition resulting in abolition of contractions in the oesophageal body (OB) and complete lower oesophageal sphincter (LOS) relaxation which is followed by peristalsis and LOS contraction. The aim of this study was to evaluate the yield of MRS to detect abnormalities in inhibitory or excitatory oesophageal mechanisms in patients with oesophageal symptoms and either normal standard manometry or ineffective oesophageal motility (IOM). MRS (five water swallows, 2 mL, separated by 2-3 s) was evaluated in 23 healthy subjects, 109 symptomatic patients with normal standard sleeve manometry and in 48 patients with IOM. Healthy subjects had complete inhibition of OB motility during MRS and a strong motor response after MRS, i.e. amplitude of OB contractions in the oesophageal body and LOS tone being higher than after single swallows. Almost 70% of patients with oesophageal symptoms and normal manometry had abnormal MRS, mainly consistent on inability to increase amplitude of OB contractions after MRS. Nearly, half of the patients with IOM were able to normalize OB contractions after MRS. MRS is a simple complementary test that can be added to standard oesophageal manometry. Two-thirds of patients with normal manometry show abnormal MRS that could potentially underlie their symptoms. A normal response to MRS in patients with severe IOM might be used to predict response to prokinetic treatment.

Evaluation and management of neonatal dysphagia: impact of pharyngoesophageal motility studies and multidisciplinary feeding strategy

BACKGROUND AND OBJECTIVES

Abnormal swallowing (dysphagia) among neonates is commonly evaluated using the videofluoroscopic swallow study (VSS). Radiological findings considered high risk for administration of oral feeding include nasopharyngeal reflux, laryngeal penetration, aspiration, or pooling. Our aims were to determine pharyngoesophageal motility correlates in neonates with dysphagia and the impact of multidisciplinary feeding strategy.

METHODS

Twenty dysphagic neonates (mean gestation +/- standard deviation [SD] = 30.9 +/- 4.9 weeks; median 31.1 weeks; range = 23.7-38.6 weeks) with abnormal VSS results were evaluated at 49.9 +/- 16.5 weeks (median 41.36 weeks) postmenstrual age. The subjects underwent a swallow-integrated pharyngoesophageal motility assessment of basal and adaptive swallowing reflexes using a micromanometry catheter and pneumohydraulic water perfusion system. Based on observations during the motility study, multidisciplinary feeding strategies were applied and included postural adaptation, sensory modification, hunger manipulation, and operant conditioning methods. To discriminate pharyngoesophageal manometry correlates between oral feeders and tube feeders, data were stratified based on the primary feeding method at discharge, oral feeding versus tube feeding.

RESULTS

At discharge, 15 of 20 dysphagic neonates achieved oral feeding success, and the rest required chronic tube feeding. Pharyngoesophageal manometry correlates were significantly different (P < 0.05) between the primary oral feeders versus the chronic tube feeders for swallow frequency, swallow propagation, presence of adaptive peristaltic reflexes, oral feeding challenge test results, and upper esophageal sphincter tone. VSS results or disease characteristics had little effect on the feeding outcomes (P = NS).

CONCLUSIONS

Swallow-integrated esophageal motility studies permit prolonged evaluation of swallowing reflexes and responses to stimuli under controlled conditions at cribside. The dysfunctional neuromotor mechanisms may be responsible for neonatal dysphagia or its consequences. Manometry may be a better predictor than VSS in identifying patients who are likely to succeed in vigorous intervention programs.

Proximal versus distal oesophageal motility as assessed by combined impedance and manometry

BACKGROUND

Regional differences in oesophageal motility have been shown in primary peristalsis, but it is unclear whether such differences occur in secondary peristalsis. We investigated whether oesophageal motor function differs between the proximal and distal oesophagus.

METHODS

Eleven healthy subjects were studied with combined impedance and manometry. Saline and solid agar boluses of 5 ml were applied for primary peristalsis, and secondary peristalsis was stimulated by rapid mid-oesophageal injections of saline. Impedance tracings were analysed and compared for bolus presence time, bolus transit time in the proximal and distal oesophagus.

RESULTS

Most of the manometric parameters were not significantly different between the proximal and distal oesophagus. Bolus presence time was longer in the distal oesophagus for both primary peristalsis and secondary peristalsis (p<0.001). The proximal bolus transit time was shorter than the distal bolus transit time during saline and solid swallows (p<0.001). Bolus transit time and bolus presence time were shorter for primary peristalsis than secondary peristalsis induced by saline injection.

CONCLUSION

Our data demonstrated that the impedance technique can successfully detect functional differences between the proximal and distal oesophagus, and such differences were still noticeable when the oesophagus was directly stimulated by saline injection.

Oesophageal bolus transit and clearance by secondary peristalsis in normal individuals

BACKGROUND

Secondary peristalsis is important for the clearance of retained refluxate or material from the oesophagus. Combined impedance and manometry can directly detect both oesophageal contraction and bolus transit.

AIM

To apply combined impedance and manometry to characterize oesophageal bolus transit and clearance by secondary peristalsis in healthy individuals.

METHODS

Eleven healthy volunteers underwent combined impedance and manometry with a catheter containing seven impedance-measuring segments and eight water-perfusion pressure transducers. Saline and solid agar boluses of 5 ml were applied for primary peristalsis and secondary peristalsis was stimulated by rapid mid-oesophageal injections of saline.

RESULTS

The rate for complete bolus clearance of secondary peristalsis with saline injections was less than that of primary peristalsis with saline swallows (69 vs. 95%, P=0.02). No statistical difference in bolus propagation time between primary and secondary peristalsis was observed (P=0.45). Bolus presence time of secondary peristalsis was significantly longer than that of primary peristalsis for all impedance-measuring segments (all P<0.05). Solid swallows differed from saline swallows with lower rate of complete bolus transit and longer bolus transit time.

CONCLUSION

Our data show that the impedance technique can successfully characterize oesophageal bolus transit and clearance by secondary peristalsis. These findings suggest that secondary peristalsis may be less effective than primary peristalsis regarding oesophageal transit and clearance of a liquid bolus.

Oesophageal peristaltic transition zone defects: real but few and far between

This study analysed the association between oesophageal transition zone (TZ) defects [characterized by a delay and/or spatial gap between the terminus of the proximal oesophageal (striated muscle) contraction and the initiation of the distal oesophageal (smooth muscle) contraction] and dysphagia in a large patient cohort. Four hundred consecutive patients (178 with dysphagia) and 75 controls were studied with 36-channel high-resolution manometry (HRM). The resultant pressure topography plots were first analysed for impaired oesophagogastric junction (OGJ) relaxation, distal segment contractile abnormalities, and proximal contractile abnormalities using normal values from the 75 controls. If these aspects of oesophageal motility were deemed normal, the TZ was characterized by length and duration between the proximal and distal contractions using a 20 mmHg isobaric contour to establish the segment boundaries. Patients were then classified according to whether or not they exhibited TZ defects (spatial separation or delay) and the occurrence of unexplained dysphagia. Of the 400 patients, 267 were suitable for TZ analysis and of these 55 had a spatial or temporal TZ measurement exceeding the 95th percentile of the controls (2 cm, 1 s). Exactly 34.6% of the patients (n = 19) with spatial and/or temporal TZ defects had unexplained dysphagia, which was significantly more than seen with normal TZ dimensions (19.8%). Although far less common than distal peristaltic or OGJ abnormailites, TZ defects may be related to dysphagia in a minority of patients (<4% in this series) and should be considered a distinct oesophageal motility disorder.

Physiology of the oesophageal transition zone in the presence of chronic bolus retention: studies using concurrent high resolution manometry and digital fluoroscopy

Distinct contraction waves (CWs) exist above and below the transition zone (TZ) between the striated and smooth muscle oesophagus. We hypothesize that bolus transport is impaired in patients with abnormal spatio-temporal coordination and/or contractile pressure in the TZ. Concurrent high resolution manometry and digital fluoroscopy were performed in healthy subjects and patients with reflux oesophagitis; a condition associated with ineffective oesophageal contractility and clearance. A detailed analysis of space-time variations in bolus movement, intra-bolus and intra-luminal pressure was performed on 17 normal studies and nine studies in oesophagitis patients with impaired bolus transit using an interactive computer based system. Compared with normal controls, oesophagitis patients had greater spatial separation between the upper and lower CW tails [median 5.2 cm (range 4.4-5.6) vs 3.1 cm (2.2-3.7)], the average relative pressure within the TZ region (TZ strength) was lower [30.8 mmHg (28.3-36.5) vs 45.8 mmHg (36.1-55.7), P < 0.001], and the risk of bolus retention was higher (90%vs 12%; P < 0.01). The presence of bolus retention was associated with a wider spatial separation of the upper and lower CWs (>3 cm, the upper limit of normal; P < 0.002), independent of the presence of oesophagitis. We conclude that bolus retention in the TZ is associated with excessively wide spatial separation between the upper and lower CWs and lower TZ muscle squeeze. These findings provide a physio-mechanical basis for the occurrence of bolus retention at the level of the aortic arch, and may underlie impaired clearance with reflux oesophagitis.

Influence of bolus consistency and position on esophageal high-resolution manometry findings

BACKGROUND

Conventional esophageal manometry evaluating liquid swallows in the recumbent position measures pressure changes at a limited number of sites and does not assess motility during solid swallows in the physiologic upright position.

AIM

To evaluate esophageal motility abnormalities during water and bread swallows in the upright and recumbent positions using high-resolution manometry (HRM).

METHODS

Thirty-two-channel HRM testing was performed using water (10 ml each) and bread swallows in the upright and recumbent positions. The swallows were considered normal if the distal peristaltic segment >30 mmHg was >5 cm, ineffective if the 30-mmHg pressure band was <5 cm, and simultaneous if the onset velocity of the 30 mmHg pressure band was >8 cm/s. Abnormal esophageal manometry was defined as the presence of > or =30% ineffective and/or > or =20% simultaneous contractions.

RESULTS

The data from 96 patients (48 F; mean age 51 years, range 17-79) evaluated for dysphagia (56%), chest pain (22%), and gastroesophageal reflux disease (GERD) symptoms (22%) were reviewed. During recumbent water swallows, patients with dysphagia, chest pain, and GERD had a similar prevalence of motility abnormalities. During upright bread swallows, motility abnormalities were more frequent (p = 0.01) in patients with chest pain (71%) and GERD (67%) compared to patients with dysphagia (37%).

CONCLUSIONS

Evaluating bread swallows in the upright position reveals differences in motility abnormalities overlooked by liquid swallows alone.

Combined multichannel intraluminal impedance and manometry testing

Oesophageal manometry has been considered the "gold standard" test for the evaluation of oesophageal motility. Oesophageal manometry allows physicians to assess peristalsis by using informations about the shape, amplitude and duration of the oesophageal contraction, but it does not offer direct information about bolus transit through the oesophagus. Recent studies demonstrate that combined impedance-manometry provides important additional information about oesophageal motility as compared to conventional manometry such as: (1) monitoring of bolus transport patterns without the use of radiation, (2) calculation of bolus transit parameters, (3) evaluation of bolus clearance and (4) investigation of the relationships between bolus transit and LES relaxation. These changes could potentially improve diagnostic accuracy of oesophageal motility testing, advancing both clinical and basic research. This review focuses on current aspects of the novel technology of combined impedance-manometry for oesophageal motility testing.

Sildenafil relieves symptoms and normalizes motility in patients with oesophageal spasm: a report of two cases

Oesophageal spasm presents with dysphagia and chest pain. Current treatments are limited by poor efficacy and side effects. Studies in health and oesophageal dysmotility show that sildenafil reduces peristaltic pressure and velocity; however the clinical efficacy and tolerability in symptomatic oesophageal spasm remains uncertain. We provided open-label sildenafil treatment to two patients with severe, treatment resistant symptoms associated with oesophageal spasm. The effects of sildenafil on oesophageal function and symptoms were documented by high resolution manometry (HRM). Patients were followed up to assess the efficacy of maintenance treatment with sildenafil b.i.d. HRM revealed focal and diffuse spasm in the smooth muscle oesophagus that were associated with symptoms in both cases, especially on swallowing solids. Lower oesophageal sphincter function was normal. A therapeutic trial of 25-50 mg sildenafil suppressed oesophageal contraction almost completely for water swallows; however effective, coordinated peristalsis returned with reduced frequency of spasm for solid swallows. Dysphagia and chest pain resolved during the therapeutic trial and efficacy was maintained on maintenance treatment with 25-50 mg sildenafil b.i.d. without troublesome side effects. This report shows that sildenafil can improve oesophageal function and relieve dysphagia and chest pain in patients with oesophageal spasm in whom other treatments have failed.

Esophageal motor and sensory disorders: presentation, evaluation, and treatment

Esophageal motor and sensory disorders are relatively rare conditions in the general population and afflicted patients are often initially misdiagnosed as having gastroesophageal reflux disease. Tests for these disorders have imperfect gold standards and are adjuncts to sound diagnostic reasoning. Treatments are palliative and have not been rigorously evaluated for some disorders. Symptoms and complications from disease progression and relapse are common, so that patients need continued follow-up.

Technological insights: Combined impedance manometry for esophageal motility testing-current results and further implications

This review focuses on current aspects of the novel technology of combined impedance manometry for esophageal motility testing. It presents methodological features, summarizes current results and discusses implications for further research. The combined technique assesses simultaneously bolus transport and associated peristalsis, thus allowing detailed analysis of the relationships between bolus transit and esophageal motility. Recent studies demonstrate that combined impedance manometry provides important additional information about esophageal motility as compared to conventional manometry: (1) monitoring of bolus transport patterns, (2) calculation of bolus transit parameters, (3) evaluation of bolus clearance, (4) monitoring of swallow associated events such as air movement and reflux, and (5) investigation of the relationships between bolus transit and LES relaxation. Studies with healthy subjects have identified several useful parameters for comprehensive assessment of eosphageal function. These parameters were found to be pathological in patients with classical achalasia, mild GERD, and ineffective esophageal motility. The technology of combined impedance manometry provides an important new tool for esophageal function testing, advancing both clinical and basic research. However, several important issues remain to be standardized to make the technique suitable for widely clinical use.

The effects of tegaserod on oesophageal function and bolus transport in healthy volunteers: studies using concurrent high-resolution manometry and videofluoroscopy

BACKGROUND

Tegaserod is a partial 5-hydroxytryptamine 4 receptor agonist with prokinetic effects on the gastrointestinal tract, its effects on oesophageal function are unknown.

AIM

A randomized, placebo controlled, double-blind trial assessed the effect of tegaserod on the oesophagus in healthy, asymptomatic subjects.

METHOD

A 7-day course of tegaserod 6 mg b.d. vs. placebo was prescribed (n = 17/21 completed both phases of study). High-resolution manometry and pH measurements were performed before and after a test meal. Bolus transport of liquids and solids was studied by high-resolution manometry and videofluoroscopy.

RESULTS

Tegaserod had no effect on lower oesophageal sphincter pressure compared with placebo, peristaltic velocity increased (P < 0.001) and distal contractile pressure decreased slightly (P < 0.05). Transient lower oesophageal sphincter relaxations and reflux were infrequent regardless of treatment. During the studies of bolus transport, high-resolution manometry revealed that tegaserod promoted mid-oesophageal contractility (P < 0.02) and shortened the 'proximal transition zone' (P < 0.05), the level where bolus escape occurred most frequently. These effects had no effect on liquid bolus transport; however a non-significant trend to improved solid bolus transport was observed (66% vs. 31%;P = 0.07).

CONCLUSION

Tegaserod did not alter lower oesophageal sphincter pressure, but had significant effects on peristaltic function. High-resolution manometry promoted mid-oesophageal contractility during bolus transport. This effect was associated with a non-significant trend to improved solid bolus transit.

Morphologic and biomechanical changes of rat oesophagus in experimental diabetes

AIM: To study morphologic and biomechanical changes of oesophagus in diabetes rats.

METHODS: Diabetes was induced by a single injection of streptozotocin (STZ). The type of diabetes mellitus induced by parenteral STZ administration in rats was insulin-dependent (type I). The samples were excised and studied in vitro using a self-developed biomaterial test machine.

RESULTS: The body mass was decreased after 4 d with STZ treatment. The length of esophagus shortened after 4, 7, 14 d. The opening angle increased after 14 d. The shear, longitudinal and circumferential stiffness were obviously raised after 28 d of STZ treatment.

CONCLUSION: The changes of passive biomechanical properties reflect intra-structural alteration of tissue to a certain extent. This alteration will lead to some dysfunction of movement. For example, tension of esophageal wall will change due to some obstructive disease.

Modeling of esophageal bolus flow by functional data analysis of scintigrams

Peristaltic forces cause a topographic, time-dependent distribution of bolus mass during its esophageal transport. A two-dimensional spatial-temporal pattern (profile) of local transit times is constructed by computer-based double compression of scintigraphic images sampled from whole swallows. Reconstruction by Gaussian bands and modeling this pattern discloses transient ellipsoidal bolus structures. The structures studied in 10 healthy volunteers present highly reproducible quantitative parameters for marking a region-specificity of transit times, which is related to the known region-selectivity of esophageal functions. Correlation of bolus flow with the dynamics of peristalsis is essential for understanding the complex mechanisms of esophageal transport as well as for diagnostic discrimination of disturbances of bolus flow.

Detection of small bolus volumes using multiple intraluminal impedance in preterm infants

BACKGROUND

Multiple intraluminal impedance (MII) is a new technique that allows detection of reflux and swallows via changes in impedance caused by a liquid bolus inside the esophagus. The method is independent of pH. The authors studied the ability of this technique to detect the small bolus volumes potentially occurring in young infants.

METHODS

Ten preterm infants (median gestational age at birth, 33 weeks; range, 25-36 weeks; age at study, 9 days; range, 2-39 days) underwent 10 instillations each of 0.1 mL to 0.5 mL saline while MII was recorded via a 2.4-mm nasogastric catheter. MII signals were analyzed for swallows, defined as a decrease in impedance starting within 1 minute. From the liquid instillation in the most proximal channel and extending downward, impedance changes during these induced swallows were compared with those occurring during spontaneous swallows.

RESULTS

All 100 liquid instillations resulted in a typical impedance pattern, occurring after a median interval of 4.4 seconds (range, 1.8-8.9 seconds). The decrease in impedance was more pronounced than after spontaneous swallows (30% vs. 24%, P < 0.03) and extended downward more rapidly (12.3 cm/s vs. 5.8 cm/s, P < 0.01).

CONCLUSION

Bolus transport of small liquid volumes can be detected via MII.

Dysphagia after antireflux surgery

BACKGROUND

Dysphagia is experienced by many patients after antireflux surgery. This literature review examines factors associated with the development, prediction and management of postoperative dysphagia.

METHODS

Published studies examining issues related to dysphagia, gastro-oesophageal reflux and fundoplication were reviewed.

RESULTS

Postoperative dysphagia is usually temporary but proves troublesome for 5--10 per cent of patients. Technical modifications, such as a partial wrap, division of short gastric vessels and method of hiatal closure, have not conclusively reduced its incidence. There is no reliable preoperative test to predict dysphagia.

CONCLUSION

It is uncertain whether postoperative dysphagia arises from patient predilection or is largely a consequence of mechanical changes created by fundoplication. Anatomical errors account for a significant proportion of patients referred for correction of dysphagia but these are uncommon in large single-institution studies. Abnormal manometry cannot predict dysphagia and, on current evidence, 'tailoring' the operation does not prevent its occurrence.

Bolus transit assessed by an esophageal stress test in postfundoplication dysphagia

INTRODUCTION

Dysphagia is common after Nissen fundoplication but the relationship between dysphagia and bolus transit is poorly defined. This study compared bolus transit of fundoplication patients to normal individuals.

METHODS

Twelve fundoplication patients and 20 healthy volunteers rated their ability to swallow eight bolus consistencies from no difficulty (0) to extreme difficulty (3) to compute a dysphagia score (range = 0-24). A 16-lumen manometric assembly was positioned across the esophagogastric junction (EGJ) and subjects were imaged fluoroscopically in a supine posture while swallowing 5 cc liquid barium and a 5-cc marshmallow-like viscoelastic barium bolus. Videofluoroscopic images were analyzed for total esophageal transit time and the fraction of time required to cross the EGJ. Manometric tracings were analyzed for the intrabolus pressure proximal to the EGJ, intragastric pressure, and distal peristaltic amplitude for each bolus.

RESULTS

Dysphagia scores for fundoplication patients were significantly higher (7.3 +/- 5.1, range = 1-17) than for normals (0.5 +/- 0.6, range = 0-2). This correlated with longer total transit times for liquids and solids (r = 0.60, P < 0.01) and a greater percentage of transit time attributable to the EGJ transit. Retrograde flow at the EGJ (escape of bolus proximally up the esophagus) and peristaltic dysfunction were more frequent in fundoplication patients. However, no differences existed in manometric parameters between groups.

CONCLUSIONS

Fundoplication impairs both liquid and solid esophageal bolus transit. Dysphagia perceived by fundoplication patients correlated with increased transit time, particularly across the EGJ. Combined quantitative evaluation with manometry and fluoroscopy reveals functional defects in fundoplication subjects, which are not evident by either modality alone.