Exploring pyloric dynamics in stenting using a distensibility technique.

BACKGROUND: Perforated duodenal ulcers can be treated with a covered stent. Stent migration is a severe complication, sometimes requiring surgery. Pyloric physiology during stent treatment has not been studied and mechanisms for migration are unknown. The aim of this study was to investigate the pyloric response to distention, mimicking stent treatment, using the EndoFLIP. METHODS: A nonsurvival study in five pigs was carried out, followed by a pilot study in one volunteer. Animals were gastroscoped during anaesthesia and the EndoFLIP was placed straddling the pylorus. Baseline distensibility readings were performed at stepwise balloon distentions to 20, 30, 40, and 50 mL, measuring pyloric cross-sectional area and pressure. Measurements were repeated after administration of a prokinetic drug and after a liquid meal. In the human study, readings were performed in conscious sedation at baseline and after stimulation with metoclopramide. KEY RESULTS: During baseline readings, the pylorus was shown to open more with increasing distention together with higher amplitude motility waves. Reaching maximum distention-volume (50 mL), pyloric pressure increased significantly (P = 0.016), and motility waves disappeared. After prokinetic stimulation, the pressure decreased and the motility waves increased in frequency and amplitude. After food stimulation, the pressure stayed low and the motility showed increase in amplitude. During both tests, the pylorus showed higher pressure and lack of motility waves at maximum probe distention. CONCLUSIONS AND INFERENCES: The pylorus seems to act as a sphincter at low distention but when further dilated starts acting as a pump. Fully distended the pyloric motility disappears and the pressure remains high, suggesting that a stent with high-radial force might show less migration.

Botulinum toxin for upper oesophageal sphincter dysfunction in neurological swallowing disorders.

BACKGROUND: Adequate upper oesophageal sphincter (UOS) opening is critical to safe and efficient swallowing due to the close proximity of the UOS to the airway entrance. Many people with neurological conditions, progressive and non-progressive, present with UOS dysfunction. The consequences for the person include difficulty swallowing food with subsequent choking and aspiration (passage of material into the trachea beyond the level of the true vocal cords). Clinical complications include aspiration pneumonia, weight loss, dehydration and malnutrition. Tube feeding is often indicated but is associated with increased mortality. Quality of life is also frequently impacted. A range of interventions exist that aim to improve UOS function and swallowing. These include compensatory strategies, rehabilitation techniques, pharmacological interventions and surgery. Over the last two decades, botulinum toxin has been gaining popularity as an intervention for UOS dysfunction, with some evidence to suggest that it is successful in improving swallow function. Despite a number of studies investigating its efficacy, there is a lack of consensus regarding whether this intervention is effective in improving swallowing for individuals with UOS dysfunction associated with neurological disease. OBJECTIVES: To establish the efficacy and safety of botulinum toxin use aimed at improving UOS dysfunction in people with swallowing difficulties (dysphagia) associated with non-progressive and progressive neurological disease. SEARCH METHODS: We searched the following electronic databases for published trials: the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE (1950 to 2013); EMBASE (1980 to 2013); AMED (Allied and Complementary Medicine) (1941 to 2013); CINAHL (Cumulative Index to Nursing and Allied Health Literature) (1937 to 2013). We also searched major clinical trials registers: CCT (http://www.controlled-trials.com); Clinical Trials (http://www.clinicaltrials.gov); Chinese Clinical Trial Register (www.chictr.org); ACTR (http://www.actr.org.au/. We examined the reference lists of all potentially relevant studies to identify further relevant trials. We handsearched published abstracts of conference proceedings from both the Dysphagia Research Society and the European Society of Swallowing Disorders. Digestive Disease Week (published in Gastroenterology) was also handsearched. Additionally, we searched ProQuest Dissertations & Theses for dissertation abstracts. SELECTION CRITERIA: Only randomised controlled trials were sought. DATA COLLECTION AND ANALYSIS: Independent searches were completed by JR, AM, MC and MW. Two review authors (JR and MW) independently inspected titles, abstracts and key words identified from the literature search. MAIN RESULTS: No randomised controlled studies were retrieved. Twenty-nine studies were excluded, mainly on the basis of trial design. AUTHORS' CONCLUSIONS: It was not possible to reach a conclusion on the efficacy and safety of botulinum toxin as an intervention for people with UOS dysfunction and neurological disease. There is insufficient evidence to inform clinical practice. Directions for future research are provided.

Innovative techniques in evaluating the esophagus; imaging of esophageal morphology and function; and drugs for esophageal disease.

This paper reporting on techniques for esophageal evaluation and imaging and drugs for esophageal disease includes commentaries on endoscopy techniques including dye-based high-resolution and dye-less high-definition endoscopy; the shift from CT to MRI guidance in tumor delineation for radiation therapy; the role of functional lumen imaging in measuring esophageal distensibility; electrical stimulation of the lower esophageal sphincter (LES) as an alternative to fundoduplication for treatment of gastroesophageal reflux disease (GERD); the morphological findings of reflux esophagitis and esophageal dysmotility on double-contrast esophagography; the value of videofluoroscopy in assessing protecting mechanisms in patients with chronic reflux or swallowing disorders; targeting visceral hypersensitivity in the treatment of refractory GERD; and the symptoms and treatments of nighttime reflux and nocturnal acid breakthrough (NAB).

Defining esophageal landmarks, gastroesophageal reflux disease, and Barrett's esophagus.

The following paper on gastroesophageal reflux disease (GERD) and Barrett's esophagus (BE) includes commentaries on defining esophageal landmarks; new techniques for evaluating upper esophageal sphincter (UES) tone; differential diagnosis of GERD, BE, and hiatal hernia (HH); the use of high-resolution manometry for evaluation of reflux; the role of fundic relaxation in reflux; the use of 24-h esophageal pH-impedance testing in differentiating acid from nonacid reflux and its potential inclusion in future Rome criteria; classification of endoscopic findings in GERD; the search for the cell origin that generates BE; and the relationship between BE, Barrett's carcinoma, and obesity.

Functional lumen imaging probe to assess geometric changes in the esophagogastric junction following endolumenal fundoplication.

BACKGROUND: The functional lumen imaging probe (FLIP) uses impedance planimetry to measure the geometry of a distensible organ. The purpose of this study was to evaluate FLIP as a method to determine structural changes at the gastroesophageal junction (GEJ) following transoral incisionless fundoplication (TIF) and compare these findings with the accepted methods of esophageal testing. METHODS: Two different approaches (TIF1.0 and 2.0) using the EsophyX™ device were performed in six and five animals, respectively. Three dogs underwent a sham procedure. FLIP measurements were performed pre- and post-procedure and at 2-week follow-up. Upper endoscopy, manometry, and 48-h pH testing were also performed at each time point. FLIP was performed in ten patients before and 3 months after TIF. RESULTS: Following TIF procedures, there was a significant decrease in cross-sectional area (CSA) of GEJ compared to baseline; however, the CSA of both groups returned to baseline at 2-week follow-up. The FLIP results were supported with pH testing and correlated highly with both measures of GEJ structural integrity (LES and cardia circumference). Following TIF in humans, there was a decrease in GEJ distensibility compared to baseline that persisted to the 3-month evaluation. CONCLUSION: FLIP is able to measure and display changes in tissue distensibility at the GEJ, and results correlate with established methods of testing. FLIP may represent a single testing modality by which to diagnose GERD and evaluate the outcome after antireflux surgery.

Esophagogastric junction distensibility after fundoplication assessed with a novel functional luminal imaging probe.

OBJECTIVE: The aim of the study was to compare the esophagogastric junction (EGJ) compliance in response to controlled distension in fundoplication (FP) patients and controls using the functional luminal imaging probe (FLIP). BACKGROUND: FP aims to replicate normal EGJ distensibility. FLIP is a new technology that uses impedance planimetry to measure intraluminal cross-sectional area (CSA) during controlled distension. METHODS: Ten controls and ten FP patients were studied with high-resolution esophageal pressure topography (HREPT) and then the FLIP placed across the EGJ. Deglutitive and interdeglutitive EGJ distensibility was assessed with volume-controlled distension. The FLIP measured eight CSAs spaced 4 mm apart within a cylindrical saline-filled bag along with the corresponding intrabag pressure. RESULTS: The EGJ formed an hourglass shape during distensions with the central constriction at the diaphragmatic hiatus. The distensibility of the hiatus was significantly greater during deglutitive relaxation in both subject groups, but FP patients exhibited reduced EGJ distensibility and compliance compared to controls. During the interglutitive period, the corresponding increase in intrabag pressures at larger volumes were also greater in FP patients implying a longer segment of EGJ constriction. The EGJ distensibility characteristics did not correlate with HREPT measures. CONCLUSIONS: FLIP technology was used to compare EGJ distensibility in FP patients and control subjects. The least distensible locus within the EGJ was always at the hiatus. EGJ distensibility was significantly reduced, and the length of constriction increased in FP patients. Future FLIP studies will compare patients with and without post-FP dysphagia and gas bloat, symptoms suggestive of an overly restrictive FP.

Functional luminal imaging probe geometric and histomorphologic analysis of abdominal wall wound induced by different trocars in pigs.

BACKGROUND: This study aimed to investigate wound geometry and tissue damage caused by several different trocar types using a quantitative functional luminal imaging probe (FLIP) geometric profile and histomorphologic analysis. METHODS: Four pigs were used in this study. After general anesthesia, six different trocars were randomly inserted at preselected locations in the porcine abdominal wall. The hydration status of the animals was monitored and maintained. A bag mounted on a FLIP was used to profile the geometry of the trocar holes during distension. After the FLIP study, the abdominal wall surrounding the trocar holes was harvested. The tissue was fixed in neutral 10% buffered formalin solution for more than 24 h. The samples contained control tissue (undamaged) and test tissue (damaged) through the entire rectangular tissue block. Approximately four to seven slides were cut parallel to the surface from each sample. Each slide was photographed, and the morphometry of the hole and damaged areas were measured and displayed three-dimensionally. The histologic sections were analyzed with regard to acute damage, bleeding, and acute inflammation of the skin, muscle, and fascia. RESULTS: The FLIP study demonstrated differences between the six trocars. These were mainly due to differences between the Versaport Plus V2 bladed trocar with the smooth cannula, the Applied Medical Separator nonbladed access system with threaded cannula, and the VersaStep Plus trocar. The morphometry data showed the smallest hole and damage areas for the Versaport Plus V2 bladed trocar with the smooth cannula. The damaged area divided by the trocar hole area was smallest for the VersaStep plus trocar and the Ethicon Endopath bladed trocar with a stability cannula (p < 0.05). The histologic analysis showed that the VersaStep Plus trocar and the Ethicon Endopath bladed trocar with a stability cannula gave the least bleeding and inflammation (p < 0.05). CONCLUSION: An agreement was found between the geometric data obtained by FLIP, the morphometric analysis, and the histology.

Transoral endoscopic fundoplication in the treatment of gastroesophageal reflux disease: the anatomic and physiologic basis for reconstruction of the esophagogastric junction using a novel device.

OBJECTIVE: To determine the safety, mechanism of action, immediate postprocedural anatomic impact on the esophagogastric junction, and short-term efficacy of the first entirely endolumenal antireflux procedure. BACKGROUND: A safe and effective endoscopic antireflux procedure remains elusive. Transoral endolumenal surgery has enormous potential for the treatment of gastroesophageal reflux disease (GERD) and other esophagogastric diseases. A canine model was used to study a novel endoscopic device, which allows for creation of an endoluminal fundoplication. METHODS: The transoral incisionless fundoplication (TIF) was performed in 21 canines in a phase I feasibility and safety study, and in 21 canines in a phase II study that included a detailed objective assessment of the effects of 2 variants of the TIF procedure (TIF 1.0 and TIF 2.0) versus sham on esophageal physiology and esophagogastric junction (EGJ) anatomy. RESULTS: In phase I, TIF provided a safe and feasible endolumenal therapy for GERD, with histologic data that demonstrated serosal fusion of approximated full-thickness tissue plications and durability of the fundoplication. TIF procedures effectively reduced cardia circumference and improved Hill classification grade. In phase II, the TIF 2.0 procedure achieved normalization of distal esophageal acid exposure and increased lower esophageal sphincter (LES) pressure and length based on objective testing over a 2-week period. TIF 2.0 demonstrated superior results to TIF 1.0, and valve appearance and location exhibited similarity to the Nissen fundoplication by vector volume analysis. CONCLUSIONS: The TIF procedure is safe and results in a durable and functional fundoplication as well as a platform for further development and modification of the procedure, which can be use to impact outcome. This work provides the foundation for human translation and assessment of long-term outcomes.

Comparison of transesophageal endoscopic plication (TEP) with laparoscopic Nissen fundoplication (LNF) in the treatment of uncomplicated reflux disease.

BACKGROUND: Transesophageal endoscopic plication (TEP) is a novel endotherapeutic approach in the management of gastroesophageal reflux disease (GERD). This non-randomized prospective study compares TEP with laparoscopic Nissen fundoplication (LNF). METHODS: Twenty-four consecutive patients treated with LNF, and 27 managed by TEP were studied. Symptom severity scores, endoscopy, 24 h esophageal pH and esophageal manometry and quality-of-life assessments were obtained pre- and posttreatment. RESULTS: In the LNF group the mean age was 36 yr (17-68) compared with 39 yr (22-62) in the TEP group. Symptom scoring, acid regurgitation score, reduction in the requirements of proton pump inhibitors (PPIs), and quality of life remained significantly improved in both groups at a median of 1 yr [10-18 months] follow-up post procedure. However, the improvement was significantly better in symptom score (p= 0.0383) and the control of acid reflux in the LNF group (p= 0.0007). Post-procedure dysphagia was more common in the LNF group. CONCLUSION: Both techniques improved symptom score, acid regurgitation, quality of life, and reduced the requirements for PPIs. The control of heartburn and acid reflux was better for LNF. TEP, like LNF, is a safe and effective method of management of symptomatic GERD but further developments are necessary to ensure control of esophageal acid reflux.