Peristaltic Sequence Research Articles

EndoFLIP Topography: Motor Patterns in an Obstructed Esophagus

EndoFLIP Topography: Motor Patterns in an Obstructed Esophagus

Hypercontractile Esophagus From Pathophysiology to Management: Proceedings of the Pisa Symposium.

Hypercontractile esophagus (HE) is a heterogeneous major motility disorder diagnosed when ≥20% hypercontractile peristaltic sequences (distal contractile integral >8,000 mm Hg*s*cm) are present within the context of normal lower esophageal sphincter (LES) relaxation (integrated relaxation pressure < upper limit of normal) on esophageal high-resolution manometry (HRM). HE can manifest with dysphagia and chest pain, with unclear mechanisms of symptom generation. The pathophysiology of HE may entail an excessive cholinergic drive with temporal asynchrony of circular and longitudinal muscle contractions; provocative testing during HRM has also demonstrated abnormal inhibition. Hypercontractility can be limited to the esophageal body or can include the LES; rarely, the process is limited to the LES. Hypercontractility can sometimes be associated with esophagogastric junction (EGJ) outflow obstruction and increased muscle thickness. Provocative tests during HRM can increase detection of HE, reproduce symptoms, and predict delayed esophageal emptying. Regarding therapy, an empiric trial of a proton pump inhibitor, should be first considered, given the overlap with gastroesophageal reflux disease. Calcium channel blockers, nitrates, and phosphodiesterase inhibitors have been used to reduce contraction vigor but with suboptimal symptomatic response. Endoscopic treatment with botulinum toxin injection or pneumatic dilation is associated with variable response. Per-oral endoscopic myotomy may be superior to laparoscopic Heller myotomy in relieving dysphagia, but available data are scant. The presence of EGJ outflow obstruction in HE discriminates a subset of patients who may benefit from endoscopic treatment targeting the EGJ.

Esophageal hypercontractility is abolished by cholinergic blockade.

Esophageal hypercontractility (EHC) is considered a major esophageal motor disorder of unclear etiology. Different mechanisms have been proposed, including an imbalance in inhibitory and excitatory esophageal innervation. We hypothesized that patients with EHC suffer from cholinergic hyperactivity. To interrogate the excitatory and inhibitory neurotransmission in EHC by assessing the esophageal motor response to atropine (ATR) and cholecystokinin (CCK), respectively, in EHC patients. We retrospectively reviewed patients who underwent high-resolution manometry (HRM) with pharmacologic challenge in a tertiary referral center between 2007 and 2017. We identified 49 EHC patients who were categorized based on frequency of hypercontractile peristaltic sequence into "frequent" and "infrequent" and motility diagnosis groups. Deglutitive pressure metrics and esophageal motor responses to ATR (12mcg/kg iv) and CCK (40ng/kg iv) were analyzed across groups. Atropine abolished hypercontractility across all groups studied, converting nearly half of patients to a motor pattern of ineffective esophageal motility. Abnormal CCK responses primarily occurred in the patient groups with concomitant outflow obstruction. Hypercontractility is cholinergically mediated in all esophageal motor disorders. Most patients with isolated EHC appear to have excessive cholinergic drive, rather than loss of inhibitory innervation, and might be candidates for treatment with anticholinergic agents.

O34 A SLIGHTLY CRAZY BUT INFORMATIVE EXPERIMENT OF THE EFFECT OF THE HEAD DOWN (HD) POSTURE ON THE CHARACTERISTICS OF OESOPHAGEAL MOTILITY AND OESOPHAGOGASTRIC JUNCTION (OGJ) USING HIGH RESOLUTION OESOPHAGEAL MANOMETRY

Abstract Background It is known that posture (Supine Vs Sitting) variations can affect the dynamics and manometric characteristics of the OG junction and Oesophageal motility. Aims To study the effect of the Head Down (HD) upside down posture on the esophageal motility characteristics and dynamics of the OG junction using High resolution manometry. This would partially replicate the effect of Obesity (High Intraabdominal pressure) on the OGJ. Methods A single crazy (but sane) volunteer who had no symptoms of GORD served as the model for this unique experiment. A high-resolution manometry was performed using a solid-state transducer catheter with 36 channels. The study was performed in the sitting, supine and head down posture. Basal characteristics recording followed by wet swallows of 5ml of water and completed by rapid water swallows was done in each posture. Analysis was performed in the standard fashion using Chicago classification metrics. Further correlation of findings with a multipostural barium video oesophagogram is awaited. Results The procedure was completed satisfactorily in all the three postures. Satisfactory progression of swallows in a peristaltic sequence was obtained in all the 3 postures. However it was noted that there was a sequential change in the following parameters from the sitting to the supine to head down postures. Increased residual and contraction pressures in the Cricopharyngeal high pressure zone more pronounced in the HD position. Decreased amplitude of contraction of peristaltic sequences Decrease in slope of the peristaltic wave in the HD posture Diminished resting pressure in the HD position Exaggerated separation of the crural diaphragm (CD) and LES on the HD position Increased intragastric pressures in the HD position. Conclusion The above experiment is the first reported of Oesophageal function and OGJ dynamics in a completely unaided head down position using high resolution manometry and video fluoroscopy. The findings may serve to imitate the effect of Obesity on the OJ junction

Chronic daily opioid exposure is associated with dysphagia, esophageal outflow obstruction, and disordered peristalsis.

Opioid receptors are present in the esophagus, and chronic opioid therapy may be associated with esophageal dysfunction. Given the current opioid epidemic in the United States, the potential contribution of opioids to esophageal dysmotility is important from both public health and patient care perspectives.Therefore our aim is toinvestigate the potentialcontribution of opioids to dysphagia and the prevalence of major motor disorders in patients undergoing manometric evaluation. The anonymized electronic medical records of patients linked to their de-identified high-resolution manometry (HRM) studies were reviewed. The patients were grouped based on their opioid exposure history at the time of HRM: opioid-naïve and chronic daily users. The oral morphine milligram equivalent daily dose (MMED) of opioids was computed. KEYRESULTS: 10% of patients referred for esophageal HRM were taking opioid analgesics on a chronic daily basis, and they had a significantly higher prevalence of dysphagia than their opioid-naïve counterparts. The chronic daily opioid users displayed a significantly higher prevalence of achalasia type 3 (ACH3) and esophagogastric junction outflow obstruction (EGJOO) motility phenotypes. The MMED of opioids was a significant predictor of esophageal pressure metrics and motility diagnoses (P<0.0001). Chronic daily opioid intake is associated with impaired deglutitive LES relaxation and disorganized peristaltic sequence. While a minority of patients on chronic daily opioid therapy present with major esophageal motor disorders, they comprise nearly half of ACH3 and a third of EGJOO motility phenotypes.

Ineffective esophageal motility: Concepts, future directions, and conclusions from the Stanford 2018 symposium.

Ineffective esophageal motility (IEM) is a heterogenous minor motility disorder diagnosed when ≥50% ineffective peristaltic sequences (distal contractile integral <450mm Hgcms) coexist with normal lower esophageal sphincter relaxation (integrated relaxation pressure<upper limit of normal) on esophageal high-resolution manometry (HRM). Ineffective esophageal motility is not consistently related to disease states or symptoms and may be seen in asymptomatic healthy individuals. A 1-day symposium of esophageal experts reviewed existing literature on IEM, and this review represents the conclusions from the symposium. Severe IEM (>70% ineffective sequences) is associated with higher esophageal reflux burden, particularly while supine, but milder variants do not progress over time or consistently impact quality of life. Ineffective esophageal motility can be further characterized using provocative maneuvers during HRM, especially multiple rapid swallows, where augmentation of smooth muscle contraction defines contraction reserve. The presence of contraction reserve may predict better prognosis, lesser reflux burden and confidence in a standard fundoplication for surgical management of reflux. Other provocative maneuvers (solid swallows, standardized test meal, rapid drink challenge) are useful to characterize bolus transit in IEM. No effective pharmacotherapy exists, and current managements target symptoms and concurrent reflux. Novel testing modalities (baseline and mucosal impedance, functional lumen imaging probe) show promise in elucidating pathophysiology and stratifying IEM phenotypes. Specific prokinetic agents targeting esophageal smooth muscle need to be developed for precision management.

The Pressure Inversion Point (PIP): Passeʼ or Paramount

PIP is produced by diaphragmatic moverment during respiration. In conventional manometry, it was used as a landmark to locate the approximate location of the LES. However, using this landmark in small hiatal hernia (HH) can give inaccurate LES location. The role of PIP in the era of high resolution manometry (HRM) has diminished. This is especially due to the easy recognition of HH using its colored pressure topography. HH is identified by 2 distal high pressure zones with the peristaltic sequence ending at the level of the LES, distinguishing it from the diaphragmatic pressure zone. Here we present a case of 72 year old female, referred to our motility laboratory by her primary care physician. Her main complain is recurrent episodes of epigastric pain, associated with nausea, dizziness and shortness of breath. Her past medical history includes hypertension and GERD. She denied dysphagia, weight loss and any atypical GERD symptoms. The patient states she had similar attacks throughout the last 8 years. Her work up included HRM and stress perfusion cardiac MRI. The HRM showed normal peristalsis with normal LES metrics (resting pressure and integrated relaxation pressure were 19 and 14 mm/Hg respectively). The only interesting finding was the absence of detectable PIP (figure 1). The stress perfusion MRI showed no cardiac perfusion and left ventricular function pararmeters. Incidentally, the MRI showed complete intrathoracic positioning of the stomach. CT abdomin was performed and it confirmed the finding (figure 2).Figure: HRM of the case. There was absence of detectable PIP with same respiratory cyclic color fluctuation above and below the LES.Figure: A: MRI showing the presence of intrathoracic stomach, B: CT abdomen confirming the same finding.Figure: An example of normal manometry with detectable PIP at the level of the LES. The respiratory cyclic color fluctuation is inverted in the region below the LES.Discussion: Locating the PIP is relatively easy using HRM. However, one must learn to recognize the color contour appearance of this phenomenon. In addition, its presence /absence can be roughly deetermined by observing the respiratory variations in the HRM color plot. The typical blue of the intraesophageal pressure darkens with inspiration and lightens with expiration. This finding assists in locating the diaphragm and so the PIP, since intraabdominal pressure changes inversely to the intrathoracic pressure with respiration (figure 3). In our case, these respiratory cyclic pressure fluctuations were the same above and below the LES. Lessons learned: Locating the PIP is important, despite not being used in the HRM algorithm of the Chicago classification. As shown in this case, the absence of detectable PIP reflects a significant structural pathology (complete intrathoracic stomach).

Multiple rapid swallow responses segregate achalasia subtypes on high-resolution manometry.

Multiple rapid swallows (MRS) inhibit esophageal peristalsis and lower esophageal sphincter (LES) tone; a rebound excitatory response then results in an exaggerated peristaltic sequence. Multiple rapid swallows responses are dependent on intact inhibitory and excitatory neural function and could vary by subtype in achalasia spectrum disorders. Consecutive subjects with incomplete LES relaxation on high-resolution manometry (HRM) (Sierra Scientific, Los Angeles, CA, USA) in the absence of mechanical obstruction were prospectively identified. Achalasia spectrum disorders were classified and HRM plots reviewed according to Chicago criteria. Esophageal peristaltic performance and LES function were assessed after 10 wet swallows and MRS (five 2 mL water swallows 2-3 s apart). Findings were compared with 18 healthy controls (28.5 ± 0.6 years, 44% women). A total of 46 subjects (57.1 ± 2.1 years, 52.2% women) met inclusion criteria. There was complete failure of peristalsis with MRS in all subjects with achalasia subtypes 1 and 2. In contrast, 80% of achalasia subtype 3 and incomplete LES relaxation (EGJ outflow obstruction) with preserved esophageal body peristalsis had a contractile response to MRS (P < 0.001 compared with subtypes 1 and 2); controls demonstrated 94.4% peristalsis. Percent decrease in LES residual pressure during MRS (compared to wet swallows) segregated achalasia subtypes; those with aperistalsis (subtypes 1 and 2) had a lesser decline (22.6%) compared to those with retained esophageal body peristalsis (40.5%) and controls (51.3%, P < 0.001 across groups). Multiple rapid swallow responses segregate achalasia spectrum disorders into two patterns differentiated by presence or absence of esophageal body contraction response to wet swallows. These findings support subtyping of achalasia, with pathophysiologic implications.

The value of multiple rapid swallows during preoperative esophageal manometry before laparoscopic antireflux surgery

When multiple swallows are rapidly administered, esophageal peristalsis is inhibited, and pronounced lower esophageal sphincter relaxation ensues. After the last swallow of the series, a robust contraction sequence results. The authors hypothesize that multiple rapid swallows (MRS) may have value in predicting esophageal transit symptoms in patients undergoing laparoscopic antireflux surgery (LARS). Records of patients undergoing esophageal high-resolution manometry (HRM) before LARS were evaluated. The evaluation of MRS included adequate inhibitory response during swallows and the contraction pattern after MRS. Dysphagia was scored based on a product of symptom frequency and severity using 5-point Likert scales. A composite dysphagia score comprised the sum of scores for solid and liquid dysphagia, and a score of 4 or higher was considered clinically significant. The normal and abnormal MRS responses of patients with preoperative, early, and late postoperative dysphagia were compared with those of patients with no dysphagia. In this study, 63 patients (mean age, 60.3 ± 1.7 years, 48 women) undergoing HRM before LARS successfully performed MRS (median, 5 swallows; longest interval between swallows, 3.2 ± 0.1 s). After MRS, 14 patients (22.2%) had an intact peristaltic sequence. Complete failure of peristalsis was seen in 21 (33.3%), and incomplete esophageal inhibition in 25 (39.7%) of the remaining patients. When stratified by presence or absence of dysphagia, 58.3% of the subjects without dysphagia had a normal MRS response, whereas 83.3% had formation of peristaltic segments after MRS. In contrast, only 14% of the subjects with dysphagia had a normal MRS response (p ≤ 0.003 vs. the subjects with no dysphagia). Abnormal MRS responses were more prevalent in the patients with any preoperative and late postoperative dysphagia (p = 0.04 across groups) and in those with clinically significant dysphagia (p = 0.08 across groups). High-resolution manometry with MRS helps to predict dysphagia in subjects undergoing preoperative esophageal function testing before LARS.

Neural Networks: More about Flexibility Than Synaptic Strength

The leech heartbeat neural network is famous for its constancy in both architecture and functional output across animals. A recent study, however, has found that the synaptic strengths underlying this constancy are quite variable across animals.

Do Some Adolescents With Rumination Syndrome Have “Supragastric Vomiting”?

Do Some Adolescents With Rumination Syndrome Have “Supragastric Vomiting”?

Concordance Between Liquid and Viscous Esophageal Manometry and Impedance in Patients with Non-obstructive Esophageal Dysphagia

Purpose: Esophageal manometry is the traditional method for evaluating non-obstructive dysphagia, but only measures peristaltic sequence. Impedance allows for measurement of bolus movement, and when combined with manometry offers additional information in these patients. We have performed combined manometry/impedance in all patients with non-obstructive dysphagia using both liquid and viscous media since 2006. The first 58 patients in which this approach was used were analyzed for concordance in diagnosis for liquid and viscous media. Methods: We reviewed all charts of patients between 2006 and 2008, and we examined the manometric and impedance findings of 58 consecutive patients with esophageal dysphagia as their primary symptom. We excluded patients with classic achalasia, since they did not receive viscous media during routine testing in our laboratory. Liquid and viscous manometry and impedance were compared separately and then in combination. Esophageal contractions and motility disorders were classified using previously published criteria. Concordance was defined as agreement between liquid and viscous findings. Results: 72% of patients were female. The patients had a variety of diagnostic findings based on manometry/impedance: 40% normal, 33% Ineffective Esophageal Motility, and 24% Distal Esophageal Spasm, 3% Nutcracker. Concordance of manometry between liquid and viscous findings was 67%. Concordance of impedance between liquid and viscous results was 67%. Overall, combined manometry and impedance showed 50% concordance between liquid and viscous findings. Conclusion: Our data reveal less than optimal concordance between liquid and viscous manometry and impedance. The clinical importance of these findings will require prospective study to more fully assess their significance.

An air-bubble-actuated micropump for on-chip blood transportation

A novel electrolysis-based micropump using air bubbles to achieve indirect actuation is proposed and demonstrated. Compared with other electrochemical micropumps, our micropump can drive microfluids without inducing the pH value variation in the main channel and the choking/sticking phenomena of electrolytic bubbles. It is promising for biomedical applications, especially for blood transportation. Our proposed on-chip electrolysis-bubble actuator with the features of room temperature operation, low driving voltage, low power consumption and large actuation force not only can minimize the possibility of cell-damage but also may enable portable and implantable lab-on-a-chip microsystems. Utilizing our proposed hydrophobic trapeziform pattern located at the junction of the T-shaped microchannel, the micropump makes the pumped fluid in the main channel be isolated from the electrolytic bubbles. It can be used for a variety of applications without the constraints on the pumped liquid. Experimental results show that the liquid displacement and the pumping rate could be easily and accurately controlled via the signal of a two-phase peristaltic sequence and the periodic generation of electrolytic bubbles. With an applied voltage of 2.5 V, the maximum pumping rate for DI water and whole blood were 121 nl min(-1) and 88 nl min(-1), respectively, with a channel cross section of 100 x 50 microm. Maximum back-pressure of 16 kPa and 11 kPa for DI water and whole blood, respectively, were achieved in our present prototype chips.

Utility and Standards in Esophageal Manometry

Esophageal manometry is a specialized procedure used to evaluate lower and upper esophageal sphincter pressure, esophageal body contraction amplitude, and peristaltic sequence. The procedure is clinically useful in evaluation of a patient with nonstructural dysphagia, unexplained or noncardiac chest pain, a compendium of symptoms suggested because of gastroesophageal reflux disease, and in the preoperative evaluation for antireflux surgery. Manometric findings in 95 normal subjects evenly distributed across age groups were reported in 1987, and are the values still used in our and most laboratories today. The subsequent review will offer our "view" on the clinical utility of esophageal manometry, on the basis of years of experience and performance techniques that have remained constant over decades.

Multichannel intraluminal impedance and esophageal manometry data for unrestricted swallowing: establishing normal values

Standard esophageal manometric testing evaluates swallowing in the supine position using small boluses, with a recovery period imposed between swallows. Manometric tests of more physiologic unrestricted swallowing have had limited practical application due to highly variable results. The purpose of this study is to apply multichannel intraluminal impedance and manometry (MII-EM) to test esophageal function during unrestricted upright meal consumption, and to assess results in a normal healthy population. Ten healthy volunteers with normal esophageal impedance and manometry by published criteria underwent MII-EM testing using a combined 5-channel catheter. After transnasal placement of the catheter, each subject sat upright and consumed a meal that consisted of two pieces of toasted bread and two ounces of Gatorade. There were no restrictions placed on chewing, swallowing, or eating time. All data assessed by the MII-EM meal test were normally distributed. Impedance results with limited variability included the meal duration, number of swallows, postprandial emptying time and the percent of bolus presence times at 15, 10, and 5 cm above the lower esophageal sphincter. Manometric results with limited variability included the number of peristaltic sequences, mean time between these sequences and their distal esophageal amplitudes. MII-EM can be used to collect data with minimal variability in healthy subjects during unrestricted upright meal consumption. This technique may be used to identify abnormal motility patterns during physiologic swallowing.

Dynamic simulation of a peristaltic micropump considering coupled fluid flow and structural motion

This paper presents lumped-parameter simulation of dynamic characteristics of peristaltic micropumps. The pump consists of three pumping cells connected in series, each of which is equipped with a compliant diaphragm that is electrostatically actuated in a peristaltic sequence to mobilize the fluid. Diaphragm motion in each pumping cell is first represented by an effective spring subjected to hydrodynamic and electrostatic forces. These cell representations are then used to construct a system-level model for the entire pump, which accounts for both cell- and pump-level interactions of fluid flow and diaphragm vibration. As the model is based on first principles, it can be evaluated directly from the device's geometry, material properties and operating parameters without using any experimentally identified parameters. Applied to an existing pump, the model correctly predicts trends observed in experiments. The model is then used to perform a systematic analysis of the impact of geometry, materials and pump loading on device performance, demonstrating its utility as an efficient tool for peristaltic micropump design.

A Model for Gastric Banding in the Treatment of Morbid Obesity

This work establishes an animal model for nonadjustable gastric banding and characterizes the effect of gastric banding on esophageal physiology. Obstruction at the esophagogastric junction (EGJ) results in esophageal dilation and aperistalsis. Although laparoscopic gastric banding as a primary treatment of morbid obesity has been widely accepted, the effects of this therapy on esophageal function remain unknown. Twenty-five opossums were randomly divided into sham (n = 5), EGJ band (n = 5), and gastric band (n = 15) groups. Gastric and EGJ bands were surgically placed, and esophageal manometry was performed prebanding, at 2-week intervals during the banding period (up to 14 weeks), and 2 and 4 weeks after band removal. Manometric measures were equivalent prior to banding in all groups. There were no changes in LES or esophageal pressures during the study period in the sham group. During banding, there was a 36% decrease in baseline mean resting lower esophageal sphincter pressure in the gastric band group (P = 0.003). Mean distal esophageal peristaltic pressure decreased from baseline by 36% in gastric band animals (P < 0.001). The incidence of esophageal motility disorder during the study period for sham, EGJ band, and gastric band groups, was 2.9%, 42.1%, and 31.3%, respectively (P = 0.001, P = 0.381, pairwise comparisons of gastric band vs. sham and gastric band versus EGJ groups, respectively). Immediately prior to band removal, the probability of an abnormal peristaltic sequence with each swallow was 1%, 38%, and 16% for sham, EGJ, and gastric band groups, respectively (P < 0.005, pairwise comparisons of band groups with sham). Nonadjustable gastric banding results in impaired esophageal body motility, a reduction in esophageal peristaltic pressure, and a reduction in resting lower esophageal sphincter pressure. These findings suggest that gastric banding causes esophageal outlet obstruction and subsequent decompensation of peristaltic function as well as a compromise of the native antireflux mechanism.

Postprandial transduodenal bolus transport is regulated by complex peristaltic sequence

To study the relationship between the patterns of postprandial peristalsis and transduodenal bolus transport in healthy subjects. Synchronous recording of chyme transport and peristaltic activity was performed during the fasting state and after administration of a test meal using a special catheter device with cascade configuration of impedance electrodes and solid-state pressure transducers. The catheter was placed into the duodenum, where the first channel was located in the first part of the duodenum and the last channel at the duodenojejunal junction. After identification of previously defined chyme transport patterns the associated peristaltic patterns were analyzed. The interdigestive phase 3 complex was reliably recorded with both techniques. Of 497 analyzed impedance bolus transport events, 110 (22%) were short-spanned propulsive, 307 (62%) long-spanned propulsive, 70 (14%) complex propulsive, and 10 (2%) retrograde transport. Short-spanned chyme transports were predominantly associated with stationary or propagated contractions propagated over short distance. Long-spanned and complex chyme transports were predominantly associated with propulsive peristaltic patterns, which were frequently complex and comprised multiple contractions. Propagated double wave contraction, propagated contraction with a clustered contraction, and propagated cluster of contractions have been identified to be an integralted part of a peristaltic sequence in human duodenum. Combined impedancometry and manometry improves the analysis of the peristaltic patterns that are associated with postprandial transduodenal chyme transport. Postprandial transduodenal bolus transport is regulated by propulsive peristaltic patterns, which are frequently complex but well organized. This finding should be taken into consideration in the analysis of intestinal motility studies.

Absence of a deglutitive inhibition equivalent with secondary peristalsis

This study aimed to determine the interactions between closely paired swallow-induced primary peristalsis (PP) and air injection-induced secondary peristalsis (SP). Ten subjects (7 men, 18-42 yr) were studied using a catheter, including two sleeves (upper and lower esophageal sphincters), a midesophageal infusion port, and seven esophageal and two pharyngeal recording sites. Ten iterations of PP and SP were induced by 5-ml water swallows and 20-ml intraesophageal air injections, respectively. Thereafter, the interactions between PP and SP, separated by 1- to 12-s intervals, were studied in all four possible sequences: paired swallows, swallow preceded by air injection, air injection preceded by swallow, and paired air injections. Tracings were analyzed for lower esophageal sphincter relaxation, presence and integrity of peristalsis, and event interaction. Eight subjects with success rates of both >/=90% PP and >/=80% SP were analyzed (PP 97 +/- 2%, SP 90 +/- 3%). During paired PP interactions and SP followed by PP, the first sequence was inhibited by the second with intervals < 4-6 s. However, no inhibition of the first peristaltic sequence was found in either PP followed by SP trials or SP followed by air injection. In contrast to swallowing or proximal esophageal distention, air injection into the lumen of the midesophagus does not inhibit an ongoing peristaltic event. Being that the elicitation of SP in the smooth muscle esophagus is intramurally mediated, this suggests that deglutitive inhibition is a centrally mediated phenomenon rather than an intrinsic property of peristalsis.

Childhood Constipation: Is There New Light in The Tunnel?

IntroductionConstipation is a common phenomenon in childhood worldwide. The symptoms vary from mild and short-lived to severe and chronic with faecal impaction and encopresis. Although our understanding of pathophysiology has grown rapidly in recent decades, the causes and management of constipation