Gastric Accommodation Research Articles

Novel insights in the pathophysiology and management of functional dyspepsia.

Functional dyspepsia is a common functional gastrointestinal disorder with bothersome symptoms in the upper abdomen without an organic lesion that is likely to explain the complaints. Traditionally, changes in gastric physiology were held responsible for the symptoms, including delayed gastric emptying, impaired gastric accommodation and hypersensitivity to distension. However, gastric sensorimotor disturbances correlated only poorly to symptom severity and treatments targeting these abnormalities are not very effective. In the last decade, the duodenum has been identified as a key integrator in the pathophysiology of functional dyspepsia with an impaired barrier function and immune activation with a particular role for eosinophils and mast cells. Moreover, changes in the duodenal microbiota were associated to dyspeptic symptoms and eosinophil counts. PPIs – still the first line treatment for functional dyspepsia – have been shown to reduce symptoms through anti-inflammatory effects in the duodenum, similar to their effect in eosinophilic esophagitis. Finally, specific probiotic strains were effective in improvement of postprandial symptoms, most likely through an anti-inflammatory effect as demonstrated by reduced Th17 signaling. These novel insights in pathophysiology and treatment provide novel hope for patients with this challenging condition.

Diagnostic Methods for Evaluation of Gastric Motility-A Mini Review.

Gastric motility abnormalities are common in patients with disorders of gut-brain interaction, such as functional dyspepsia and gastroparesis. Accurate assessment of the gastric motility in these common disorders can help understand the underlying pathophysiology and guide effective treatment. A variety of clinically applicable diagnostic methods have been developed to objectively evaluate the presence of gastric dysmotility, including tests of gastric accommodation, antroduodenal motility, gastric emptying, and gastric myoelectrical activity. The aim of this mini review is to summarize the advances in clinically available diagnostic methods for evaluation of gastric motility and describe the advantages and disadvantages of each test.

Gastric dysmotility and gastrointestinal symptoms in myalgic encephalomyelitis/chronic fatigue syndrome

Background Gastrointestinal symptoms are common in ME/CFS, but there is a knowledge gap in the literature concerning gastrointestinal motility features and detailed symptom description. Objective In this study, we aimed to characterize gastric motility and gastric symptoms in response to a liquid meal. Methods We included 20 patients with ME/CFS with abdominal complaints who were recruited to a double-blind randomized placebo-controlled trial of Rituximab. The patients of this sub study were examined with an ultrasound drink test, and gastrointestinal symptoms were evaluated using the Rome III questionnaire and Irritable Bowel Syndrome Symptom Severity Scale (IBS-SSS) questionnaire. Results We found that patients commonly reported fullness/bloating (75%), abdominal pain (45%) and nausea (35%). Ultrasound measurements revealed lower proximal measurements of the stomach after a meal (p < 0.01) and larger fasting antral area (p = 0.019) compared to healthy controls. The patients had a stronger symptomatic response to the liquid meal compared to healthy controls regarding epigastric pain, discomfort and nausea (p < 0.05). Ninety percent of the patients reported bowel movement frequencies within the normal range but scored high on bowel habit dissatisfaction and life disruption. Conclusion The patients presented with fullness/bloating, nausea and epigastric pain, showed signs of impaired gastric accommodation and visceral hypersensitivity, showing that the gastrointestinal symptoms of ME/CFS patients are similar to functional dyspepsia. Key summary Gastrointestinal symptoms are common in ME/CFS, but there is a knowledge gap in the literature concerning gastrointestinal motility features and detailed symptom description. • In this study, patients with ME/CFS had signs of impaired gastric accommodation after a liquid meal. • Out of 20 patients, 15 patients reported fullness/bloating, 9 reported abdominal pain, and 7 reported nausea. The patients showed signs of visceral hypersensitivity on a drink test. • Our findings suggest that patients with ME/CFS share many similarities with patients with Functional Dyspepsia. The findings were not typical for Irritable Bowel Syndrome.

Probiotics in Functional Dyspepsia

Functional dyspepsia (FD) is a common disorder in everyday clinical practice identified nowadays as a multi-factorial, difficult to treat condition with a significant burden on patients' quality of life (QoL) and healthcare systems worldwide. Despite its high prevalence in the general population, the precise etiology of the disorder remains elusive, with its pathophysiological spectrum evolving over time, including variable potential mechanisms, i.e., impaired gastric accommodation, gastric motor disorders, hypersensitivity to gastric distention, disorders of the brain-gut axis, as well as less evident ones, i.e., altered duodenal microbiota composition and genetic susceptibility. In light of these implications, a definitive, universal treatment that could be beneficial for all FD patients is not available yet. Recently, probiotics have been suggested to be an effective therapeutic option that could alleviate gastrointestinal symptoms in patients with Irritable Bowel Syndrome (IBS), potentially due to anti-inflammatory properties or by modulating the complex bidirectional interactions between gastrointestinal microbiota and host crosstalk; however, their impact on the multiple aspects of FD remains ambiguous. In this review, we aim to summarize all currently available evidence for the efficacy of probiotics as a novel therapeutic approach for FD.

Nutrient Drink Test to Assess Gastric Accommodation in Cyclic Vomiting Syndrome: Single-blinded Parallel Grouped Prospective Study

Cyclic vomiting syndrome (CVS) is characterized by episodes of nausea and vomiting, separated by symptom-free intervals. The pathogenesis of CVS is poorly understood. Limited data exist on evaluating impaired gastric accommodation as a mechanistic means for symptoms. We aim to determine if CVS patients demonstrate impaired gastric accommodation applying a nutrient drink test (NDT) protocol. Through this single-blinded pilot clinical trial, patients with CVS per Rome IV critera and healthy controls were assessed for presence of impaired gastric accommodation by administering an established NDT protocol. Statistical analysis was performed, with data presented as medians and interquartile range. Eleven CVS patients and 15 healthy controls participated in the study between January 2018 and October 2018. Median age was 42.0 years and 37.0 years; majority of subjects were female, 72.7% and 73.3%, respectively. Demographics were similar between CVS and healthy controls. Almost all healthy controls (93.3%) ingested the complete 500 mL protocol, whereas a smaller proportion (72.7%) were able to complete all 4 doses in the CVS group (P = 0.188). Post-prandial visual analogue scale scores of nausea and abdominal pain were found to be significantly higher in CVS patients compared to healthy controls. To our knowledge, this is the first NDT protocol in CVS evaluating the role of impaired gastric accommodation and hypersensitivity as a possible pathophysiologic mechanism. Findings from this study suggest the presence of gastric hypersensitivity in a subset of CVS patients. These results provide the foundational data necessary for future larger testing of NDT and diagnostic accuracy in CVS.

A COMPARATIVE EVALUATION OF EFFECTIVENESS OF ACOTIAMIDE WITH RABEPRAZOLE VS MOSAPRIDE WITH RABEPRAZOLE IN PATIENTS WITH FUNCTIONAL DYSPEPSIA POST H.PYLORI ERADICATION

Background: Functional Dyspepsia is well dened when a patient had one or more of these symptoms with duration of three months or longer like post-prandial fullness, early satiation, epigastric pain and burning, bloating, nausea, vomiting and belching. Functional dyspepsia, consisting of epigastric pain syndrome and postprandial distress syndrome, is a prevalent functional gastrointestinal disorder. To date, only limited treatment options are available and conicting results in terms of efcacy have been reported. This was a prospective, com Methods: parative study carried out for a period of six months. Patient data were extracted from their medical records. Treatment outcome was evaluated based on the resolving of Symptoms using Gastrointestinal Symptom Rating Scale (GSRS), and (Hospital anxiety and depression scale) HADS scales. Descriptive statistics were used to summarize patient characteristics. Unpaired t-test and Mann Whitney test were used wherever appropriate. A total of 100 patients with conrmed funct Results: ional dyspepsia after H. pylori eradication were included.They were randomized into two study Groups namely Group 1 &amp; 2. Each Group consists of 50 patients. Patients in Group 1 treated with Acotiamide and Rabeprazole. Group 2 patients treated with Mosapride and Rabeprazole. Patients with two different treatments have shown signicant improvement in gastrointestinal symptoms. The major risk factors are consumption of junk food, tea and spicy food. Our study shows that FD is predominant in Females than Males. Minor ADRS were reported which includes Nausea, Headache, dizziness and Constipation. study till date revealed that effects of both gastroprokinetic drugs help in enhancing Gastric emptying Rate (GER) , Gastric Accommodation Rate (GAR) and helps in acceleration of intestinal transit which ultimately results in preventing relaxation peristaltic movements respectively. Our study demonstrated that Mosapride and Acotiamide were both effective and well t Conclusion: olerated in FD patients without serious side effects. We found that effectiveness of Mosapride is 86% and Acotiamide is 84% thus Mosapride offers good alternative to Acotiamide in treating post H.pylori FD patients. Further investigations with increased sample are required in order to conrm the results in depth

Gastric functional monitoring by gastric electrical impedance tomography (gEIT) suit with dual-step fuzzy clustering

Gastric Function has been successfully estimated by gastric electrical impedance tomography (gEIT) Suit with dual-step fuzzy clustering. The gEIT Suit which are made of elastic cloth with dual-planar electrodes and compact data acquisition (DAQ) system measures gastric impedance Z to visualize the gastric conductivity distribution σ. The dual-step fuzzy clustering extracts the clustered gastric conductivity distribution kσ, which accurately estimates the gastric function. The gEIT Suit with dual-step fuzzy clustering are applied to eight healthy persons during liquid meal consumption to estimate the gastric function under gastric accommodation phase of 200, 400 and 600 mL based on the gastric emptying phase. As the results, the gEIT Suit successfully estimate the gastric function. By the measured impedance Z, the subjects have a mean temporal impedance overline{Delta mathbf{Z} }= − 9.27 [Ohm] and p-value of that overline{mathbf{Z} }p(Z) = 0.0013[–]as the t-test result. In the case of gastric conductivity distribution σ, the subjects have a value of spatial mean conductivity distribution ⟨σ⟩ = 0.23[–] and p-value of that ⟨σ⟩ p(σ) = 0.0140[–]. Lastly, in the case gastric volume V, subjects have a gastric volume V = 12.44 [%] and p-value p(V) = 0.0664[–].

Parasympathetic control of gastrointestinal motility and cross-branch actions of parasympathetic neuromodulation.

Parasympathetic control of gastrointestinal motility and cross-branch actions of parasympathetic neuromodulation.

Development of an Ingestible Expandable Capsule for Weight Loss.

Obesity has grown to epidemic proportions with 2.1 billion people being overweight worldwide. A food-grade expandable capsule named EndoXpand for the treatment of overweight people was designed and developed in this study. EndoXpand consists of an inner expandable material (core), an embracing membrane, and a gelatin capsule shell. It is designed to occupy volume in the stomach and reduce hunger sensation. The occupied volume is changeable over time, dependent on the number of ingested capsules and their degradation time. This will avoid gastric accommodation to constant volume devices as seen in the use of intragastric balloons. Several materials were tested. Collagen casing was selected as the membrane and corn silk was used to tie the membrane. Dried black fungus (Auricularia auricula) was the biological material that expanded most. However, synthesized cellulose-based hydrogel expanded more and was chosen as the optimal expandable core material. The hydrogel-based EndoXpand expanded 72 times after soaking in an acidic environment for 80 min. The corn silk ligations weakened and broke after 3 h. This resulted in release of the expanded material that was designed to easily pass the pylorus and travel down the intestine for digestion or excretion. In conclusion, this study provides design and in vitro proof-of-technology data for a potential groundbreaking approach. Further studies are needed in animal models and human phase I studies.

A novel MRI-based three-dimensional model of stomach volume, surface area, and geometry in response to gastric filling and emptying.

Gastric motility and accommodation have a critical role in maintaining normal gastrointestinal homeostasis. Different modalities can be adopted to quantify those processes, that is, scintigraphy to measure emptying time and intragastric Barostat for accommodation assessment. However, magnetic resonance imaging (MRI) can assess the same parameters noninvasively without ionizing radiation. Our study aimed to develop a detailed three-dimensional (3D) MRI model of the stomach to describe gastric volumes, surface areas, wall tension distribution, and interobserver agreement. Twelve healthy volunteers underwent an MRI protocol of six axial T2-weighted acquisitions. Each dataset was used to construct a 3D model of the stomach: First, the volumes of the whole stomach, gastric liquid, and air were segmented. After landmark placing, a raw 3D model was generated from segmentation data. Subsequently, irregularities were removed, and the model was divided into compartments. Finally, surface area and 3D geometry parameters (inverse curvatures) were extracted. The inverse curvatures were used as a proxy for wall tension distribution without measuring the intragastric pressure. The model was able to describe changes in volume and surface geometry for each compartment with a distinct pattern in response to filling and emptying. The surface tension was distributed nonhomogeneously between compartments and showed dynamical changes at various time points. The presented model offers a detailed tool for evaluating gastric volumes, surface geometry, and wall tension in response to filling and emptying and will provide insights into gastric emptying and accommodation in diseases such as diabetic gastroparesis.

OR10-4 Sex as an Independent Variable in Satiety

Abstract Background Satiety is the result of postprandial physiologic events that determine the timing for the next meal by inhibiting the sensation of hunger. It is orchestrated by the brain-gut-axis, with gastric emptying and accommodation being key components of satiety and appetite sensations. Several indices have been used to quantify satiety. Longer time to empty 50% of the stomach content (GEt1/2) during a gastric emptying for solid study (GES), and lower SQ for fullness, lower SQ for satisfaction, and higher SQ for hunger after a meal challenge measured by visual analog scales (VAS) are all associated with prolonged satiety and are therefore protective against caloric overconsumption and to the development of obesity. Although obesity prevalence is higher in female compared to male subjects, there is little data on how sex affects biological indices of satiety. Methods This retrospective cohort study included patients with overweight and obesity who underwent anthropometric measurements, body composition evaluation, and satiety tests. After an 8-hour overnight fast, patients were provided a radiolabel breakfast (320kcal, 30% fat) to measure GES by scintigraphy over 4 hours and appetite sensations. We measured appetite sensations (hunger, fullness, and satisfaction) with 100-mm VAS every 30 minutes for 4 hours at baseline (before eating breakfast, i.e. VAS0') and after breakfast (VAS30' to VAS240'). The SQ for each appetite sensation was calculated with the following formula: (VAS0' – VAS30')/320. We performed univariate and multiple regression analyses to estimate the contribution of biological and anthropometric variables to GEt1/2. Results We included 743 subjects: 557 females (75%), mean age 40±11 years, mean BMI 33±8kg/m2. Compared to males, female participants had significantly higher BMI and lower height, weight, waist-to-hip ratio (W/H), and percentage lean mass (%LM). Compared to males, female participants had a slower GEt1/2 (123 vs. 98 minutes, p&amp;lt;0.0001), lower SQ for fullness (-15 vs. -12 mm, p=0.008), and lower SQ for satisfaction (-14 vs. -11 mm, p=0.01). Females had higher but not significant SQ for hunger. On univariate analysis, height, BMI, and %LM had a negative but significant correlation with GEt1/2 (R=-0.3, p&amp;lt;0.0001; R=-0.1, p=0.02; and R=-0.2, p=0.0003; respectively). On multiple regression analysis, when taking into consideration age, sex, height, W/H, and %LM, only sex (parameter estimate [PE]=6.8, p=0.02), height (PE=-82, p=0.0005), and W/H (PE=49, p=0.004) were independent predictors of GEt1/2. Conclusion This study highlights the sex differences in indices of satiety measured by GEt1/2 with a GES, and by SQ for hunger, fullness, and satisfaction with VAS. Sex is a strong independent predictor of GEt1/2. These observations highlight the importance of considering sex as a variable to understand the pathophysiologic mechanisms involved in obesity's heterogeneity. Presentation: Sunday, June 12, 2022 11:45 a.m. - 12:00 p.m.

S2861 Removal of Orbera Intragastric Balloon Using Endoscopic Ultrasound

Introduction: The Orbera intragastric balloon [IGB] was FDA-approved in the United States in 2015 for management of obesity. The balloon is placed endoscopically and requires endoscopic removal within six months. Most patients who undergo IGB placement initially experience mild gastrointestinal symptoms such as nausea, vomiting, acid reflux, and abdominal pain due to gastric accommodation. Occasionally, early removal of the balloon is necessary due to intolerable symptoms, dehydration, gastric outlet obstruction, or infection. We present a novel case of IGB removal using endoscopic ultrasound [EUS]-guided aspiration. Case Description/Methods: A twenty-four-year-old woman with obesity underwent Orbera IGB placement in the Dominican Republic without initial complication and lost forty-five pounds. Two months after IGB placement, she presented to the emergency room with two weeks of progressive epigastric pain, nausea, nonbilious but occasionally blood-streaked vomiting, inability to tolerate oral intake, and constipation. Vital signs were normal. Laboratory studies demonstrated hemoconcentration and low serum magnesium levels. She was also deficient in folate, iron, and vitamins A, D, and E. Abdominal radiograph demonstrated air and fluid in the stomach. She was admitted to the hospital for fluid resuscitation. On hospital day two, she underwent esophagogastroduodenoscopy [EGD] and EUS with removal of the IGB. On initial EGD inspection, the Orbera balloon was identified in the stomach and the scope was able to pass beyond the balloon. The scope was withdrawn and then the EUS was performed. The balloon was identified and a nineteen-gauge echotip needle was introduced into balloon. Six hundred milliliters of methylene-blue colored fluid were aspirated. The EGD scope was reintroduced and the deflated balloon was removed with a grasper. On EGD inspection after balloon removal, continuous edema and erosion of the mucosa were seen in the fundus. Post-procedure, her symptoms resolved and she was discharged home. (Figure) Discussion: As the use of IGBs for obesity management becomes more common, it is important that endoscopists have the ability to safely remove them. Medical centers that do not specialize in bariatric endoscopy are unlikely to stock IGB removal kits. Other techniques such as puncturing the balloon with biopsy forceps or a needle knife are generally ineffective. EUS-guided aspiration of an IGB was successful in this case and can be easily replicated at any institution with a endoscopist proficient in EUS.Figure 1.: a. Fully inflated Orbera intragastric balloon b. Orbera under EUS with needle catheter inserted for deflation c. Removal of fully deflated Orbera.

Indentation of a pressurized silicon stomach model – A non-invasive study of gastric wall stiffness and pressurized gastric content stiffness

Background and aimsEvaluation of gastric wall stiffness and intragastric pressure is essential for detailed assessments of gastric accommodation. However, non-invasive assessments are needed for large scale clinical studies and none of the existing methods takes abdominal wall effect into the calculation. This study aimed to assess gastric wall stiffness and gastric content stiffness as a proxy for intragastric pressure using novel mechanical modeling and non-invasive indentation tests on a silicon stomach model. MethodsA silicon stomach model (scaling 1:1 with the human stomach) was indented using a pressure algometer at intragastric pressures from 0 to 0.8 kPa. Wall thicknesses and luminal cross-sectional areas along the stomach were measured with ultrasound images. The gastric wall stiffness was compared between measurements from tensile tests on strips cut from the silicon stomach and estimations from a shell indentation model. The pressurized gastric content stiffness was predicted from a bonded two-layer axisymmetric half-space indentation model. ResultsThe gastric wall stiffness estimated from the shell indentation model showed no difference to measurements from the mechanical tests on the cutting strips (p = 0.14). The predicted gastric content stiffness was strongly associated with the intragastric pressure (r > 0.83, p < 0.001). ConclusionsThe mechanical model developed in this study can simultaneously predict the gastric wall stiffness and the pressurized gastric content stiffness. In future studies, the method can be applied to reveal intragastric pressure conditions non-invasively via the pressurized gastric content stiffness during gastric accommodation and emptying such as with magnetic resonance imaging.

Weight loss after endoscopic sleeve gastroplasty is independent of suture pattern: results from a randomized controlled trial.

Background and study aims This was a single-blind, single-center, prospective randomized controlled trial aimed at comparing the efficacy of three different suture patterns for endoscopic sleeve gastroplasty using Endomina (E-ESG). Patients and methods The suture patterns aimed to modify gastric accommodation by increasing the fundus distention ability (Group A), to reduce gastric volume (Group B) or to interrupt gastric emptying (Group C). Patients were randomized 1:1:1 and underwent clinical follow-up, gastric emptying scintigraphy, and satiety tests at baseline and 6 and 12 months post-procedure. The primary outcome was total body weight loss (TBWL) and excess weight loss (EWL) at 12 months post-procedure. Secondary outcomes included the impact of the suture patterns on gastric emptying and satiety. Results Overall, 48 patients (40 [83.3 %] female, aged 41.9 ± 9.5 years, body mass indexI 33.8 ± 2.7 kg/m 2 ) were randomized (16 in each group). In the entire cohort, mean (95 % confidence interval [CI]) TBWL and EWL at the end of the follow-up were 10.11 % (7.1–13.12) and 42.56 (28.23–56.9), respectively. There was no difference among the three study groups in terms of TBWL (95 %CI) (9.13 % [2.16–16.11] vs. 11.29 % [5.79–16.80] vs. 9.96 % [4.58–15.35]; P = 0.589) and EWL (95 %CI) (34.54 % [6.09–62.99] vs. 44.75 % [23.63–65.88] vs. 46.94 % [16.72–77.15]; P = 0.888) at 12 months post-procedure. The three groups did not differ in terms of mean gastric emptying time or in terms of satiety tests at the end of the follow-up. No serious adverse events occurred. Conclusions Three different suture patterns during E-ESG demonstrated comparable efficacy in terms of weight loss, with an overall EWL of > 25 % and TBWL of > 10 % at 12 months.

Efficacy of Slow Nutrient Drinking Test for Evaluating Postprandial Distress Symptom in Japanese Patients With Functional Dyspepsia.

Background/AimsFunctional dyspepsia (FD), one of the functional gastrointestinal disorders, is highly prevalent. Impaired gastric accommodation is proposed as a pathophysiology of FD. In order to assess gastric accommodation, a slow nutrient drinking test was developed. This study aims to evaluate the effectiveness of this slow nutrient drinking test among patients with FD in Japan.MethodsAsymptomatic/healthy participants (n = 26) and those with FD (n = 16), were enrolled. An infusion pump was used to deliver the liquid meal into cups. They were requested to score their meal-related and abdominal symptoms at 5-minute intervals, using a 100 mm visual analog scale. They were instructed to end the test when they felt unable to ingest more or until after 50 minutes.ResultsThe test ending time was significantly shorter in patients with FD than in healthy participants (22.3 ± 10.6 vs 45.0 ± 7.5 minutes, P < 0.001). The receiver operating characteristic curve indicated that the optimal cutoff time for detecting patients with FD was 30 minutes. The severity of meal-related and abdominal symptoms between healthy participants and those with FD was continuously different. Univariate and multivariate analyses revealed that the presence of symptoms of postprandial distress syndrome contributed to the short test ending time.ConclusionThe 30-minute slow nutrient drinking test is a minimally invasive method of effectively evaluating symptoms of postprandial distress syndrome among patients with FD, in Japan.

Effects on physiologic measures of appetite from intragastric balloon and endoscopic sleeve gastroplasty: results of a prospective study.

Background:Endoscopic bariatric therapies can help address widening management gaps in obesity. Their ability to facilitate weight loss is largely tied to influences on appetite through perturbations of gastric emptying and accommodation. As these tools gain traction in obesity therapy, their physiologic underpinnings require exploration, which may enhance efficacy, tolerance, and patient-tailored care.Methods:We prospectively assessed consecutive subjects with fluid-filled intragastric balloons (IGBs) (n = 18) placed between October 2016 and June 2017 or underwent endoscopic sleeve gastroplasty (ESG) (n = 23) from March 2018 to June 2018. Patients underwent physiologic appraisal at 3 months with 13C-spirulina-based gastric emptying breath test to determine time to half emptying (T50), as well as maximum tolerated volume (MTV) of a standard nutrient drink test. Changes in T50 and MTV at 3 months were compared with percent total body weight loss (%TBWL) at 3 and 6 months using best-fit linear regression.Results:The change in T50 at 3 months correlated with %TBWL at 3 months for IGB (P = 0.01) and ESG (P = 0.01) but with greater impact on %TBWL in IGB compared to ESG (R2 = 0.42 vs. 0.26). Change in T50 at 3 months was predictive of weight loss at 6 months for IGB (P = 0.01) but not ESG (P = 0.11). ESG was associated with greater decrease in MTV compared to IGB (340.25 ± 297.97 mL vs. 183.00 ± 217.13 mL, P = 0.08), indicting an enhanced effect on satiation through decreased gastric accommodation. Changes in MTV at 3 months did not correlate with %TBWL for either IGB (P = 0.26) or ESG (P = 0.49) but trended toward significance for predicting %TBWL at 6 months for ESG (P = 0.06) but not IGB (P = 0.19).Conclusion:IGB and ESG both induce weight loss but likely through distinct gastric motor function phenotypes, and gastric emptying may predict future weight loss in patients with IGB.

Postprandial symptoms in patients with symptoms of gastroparesis: roles of gastric emptying and accommodation.

Patients often are evaluated for gastroparesis because of symptoms occurring with meals. Gastric emptying scintigraphy (GES) is used for gastroparesis diagnosis, although results are not well correlated with gastroparesis symptoms. The aim of this study is to assess relationships between gastroparesis symptoms, gastric emptying (GE), and gastric accommodation (GA). Patients with symptoms of gastroparesis completed the Patient Assessment of Upper GI Symptoms (PAGI-SYM) and recorded symptoms during GES and water load satiety test (WLST), an indirect assessment for GA. A total of 109 patients with gastroparesis symptoms were assessed. Symptom severity increased after GES meal for stomach fullness, belching, nausea, abdominal burning, and abdominal pain. There was no difference in symptoms after meal between patients with delayed (n = 66) and normal (n = 42) GE. Diabetic patients (n = 26) had greater gastric retention than idiopathic patients (n = 78), but idiopathic patients had greater postprandial nausea, stomach fullness, and abdominal pain. Water consumed during WLST averaged 421 ± 245 mL. Idiopathic patients had greater nausea scores during WLST than diabetic patients. In comparison to those with normal water consumption (≥238 mL; n = 80), patients with impaired water ingestion (<238 mL; n = 26) had increased stomach fullness, early satiety, postprandial fullness, and loss of appetite on PAGI-SYM. Patients with delayed and normal GE had similar symptom profiles during GES and WLST. Idiopathic patients had less gastric retention but more symptoms after GES meal and after WLST compared with diabetic patients. Patients with impaired water consumption during WLST had increased symptoms by PAGI-SYM. These data suggest that impaired GA, rather than GE, may be important in explaining postprandial symptoms in patients with symptoms of gastroparesis.NEW & NOTEWORTHY Patients with delayed and normal gastric emptying (GE) had similar symptom profiles during gastric emptying scintigraphy (GES). Idiopathic patients with symptoms of gastroparesis had less gastric retention by GES; but more symptoms after GES meal and after water load satiety test (WLST) compared with diabetic patients. In patients with symptoms of gastroparesis, symptoms after WLST increased with decreasing water consumption. Early satiety and loss of appetite were associated with decreased water consumption during WLST. Thus, impaired accommodation and perhaps visceral hypersensitivity are important in explaining postprandial symptoms in gastroparesis.

High resolution retrograde tracing, morphological analysis, RNA sequencing and differential expression analysis of identified vagal afferent neurons innervating the muscle or mucosa in 3 different stomach regions in the rat

The functions of the stomach are powerfully influenced by the vagus nerve and vago‐vagal reflexes. The vagal afferent neurons that innervate the stomach and monitor its functional state have clearly demonstrated roles in appetite regulation, gastric accommodation and gastric emptying. In mammals with single compartment stomachs, including humans, the stomach can be divided into functional regions and the muscle and mucosal layers show region‐specific specializations. Electrophysiological and morphological studies suggest that the vagal sensory axons innervating the different regions and layers of the stomach wall have distinct properties and participate in different types of reflex controls. We therefore hypothesized that these functional and structural differences would be reflected in distinct gene expression profiles of afferent neurons, depending on the stomach region and tissue innervated. We developed methods to selectively retrogradely label afferent neurons innervating the muscle or mucosa in the corpus and antrum and the muscle in the fundus in the rat, using local microinjections of fluorescent nanospheres that diffuse minimally. Up to 30 microinjections of 30‐100nL of tracer beads were made into either the muscle or the mucosa in one stomach region in each rat under anesthesia. The animal was allowed to recover and kept for 1‐2 weeks before being humanely killed and tissues harvested. Labelled neurons were studied in situ in the nodose ganglion using confocal microscopy, immunohistochemistry and fluorescence in situ hybridization, and individual neurons collected after dissociation for RNAseq analysis. RNA sequencing was performed using pooled samples of 5‐12 neurons labelled from each region and deep sequencing (30‐50 million reads per sample), and then analyzed using minimal filtering to allow detection of genes expressed at low copy number.Nodose neurons labelled from the mucosa were significantly larger than those labelled from the muscle in both the corpus and antrum, whether quantified in situ or after dissociation, confirming that microinjections into the different stomach wall layers labelled different populations of neurons. Pairwise differential expression analyses of RNAseq data showed distinct mRNA expression profiles depending on the region innervated, and between muscle and mucosal innervating neurons in each region, based on Benjamini/Hochberg adjusted P values (Limma analysis tool). Some genes displayed region specific expression patterns while others showed tissue specific patterns (eg muscle vs mucosa) and some showed both. Among differentially expressed genes were some previously identified to specifically label gastric mucosal and muscle afferent neurons, such as somatostatin, CCKB receptor and GRP65. In addition, many other genes were differentially expressed and mRNA for genes known to be functional in vagal afferent neurons, such as ghrelin, leptin and galanin receptors, were detected. Differential expression patterns for various genes were confirmed in labelled neurons in situ using immunohistochemistry and/or in situhybridization. The data provide a rich resource for further studies of the visceral sensation in the different stomach regions and how region‐specific signaling might regulate appetite and gastric function in both normal and disease states.

Gastroparesis: A Multidisciplinary Approach to Management.

Gastroparesis is a neuromuscular disorder whose hallmark is delayed gastric emptying. It is a global challenge to the healthcare system because of poor treatment satisfaction for both the patients and clinicians, eventually leading to a reduction in the quality of life, with antecedent anxiety and depression. Although it is multifactorial in origin, diabetic, idiopathic, and drug-induced gastroparesis are the major risk factors. Disrupted interstitial cells of Cajal (ICC) and gastric dysrhythmia are pivotal to the pathogenesis, with most of the investigations targeted toward assessing gastric emptying and accommodation usually affected by distorted ICC and other neural networks. The treatment challenges can be overcome by a multidisciplinary approach involving gastroenterologists, gastrointestinal surgeons, biomedical engineers, nutritionists, psychologists, nurses, radionuclide radiologists, pharmacists, and family physicians. The exploration of the fundamental physiological processes underlying gastroparesis with the use of biomechanical materials should be given more attention by biomedical engineers to integrate innovative engineering with medicine for solving complex medical issues.

Role of Neuromodulators for the Management of Post-Gastric-Fundoplication Dyspepsia: A Retrospective Series.

Post-fundoplication dyspepsia is a common complication of gastric fundoplication surgeries. This can be attributable to the loss of fundal relaxation, decreased gastric accommodation, and/or alterations in gastric motility and sensitivity following fundoplication. The role of neuromodulators in the management of such symptoms is unknown. We retrospectively assessed the efficacy of neuromodulators such as tricyclic antidepressants, buspirone, and mirtazapine for the management of post-fundoplication dyspepsia.