Publications by authors named "John Pandolfino"

Gastroesophageal reflux disease (GERD) encompasses an array of disorders unified by the reflux of gastric contents. Because there are many potential disease manifestations, esophageal and extraesophageal, there is no single biomarker of the entire disease spectrum; a set of GERD biomarkers that each quantifies specific aspects of GERD-related pathology might be needed. We review recent reports of biomarkers of GERD, specifically in relation to endoscopically negative esophageal disease and excluding conventional pH-impedance monitoring.

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Article Synopsis
  • The functional lumen imaging probe (FLIP) enhances the study of achalasia by identifying unique esophageal contractions that standard manometry misses.
  • In a study with 51 achalasia patients and 10 healthy controls, FLIP effectively mapped esophageal muscle activity during stretching, revealing distinct contraction patterns.
  • Results highlighted significant differences in contractility between achalasia types, suggesting FLIP may aid in further subclassifying achalasia and understanding its underlying mechanisms.
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Esophageal transport is a physiological process that mechanically transports an ingested food bolus from the pharynx to the stomach via the esophagus, a multilayered muscular tube. This process involves interactions between the bolus, the esophagus, and the neurally coordinated activation of the esophageal muscles. In this work, we use an immersed boundary (IB) approach to simulate peristaltic transport in the esophagus.

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Background: In the recently reported international survey of centers performing per-oral endoscopic myotomy (POEM), 88% of operators reported obtaining routinely an early postoperative contrast esophagram. To date, there have been no studies to assess the prognostic value of early esophagram in POEM.

Methods: A retrospective review of a prospectively maintained, single-institution database of patients who underwent POEM for treatment of achalasia was conducted.

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On the basis of a fully coupled active musculomechanical model for esophageal transport, we aimed to find the roles of circular muscle (CM) contraction and longitudinal muscle (LM) shortening in esophageal transport, and the influence of their coordination. Two groups of studies were conducted using a computational model. In the first group, bolus transport with only CM contraction, only LM shortening, or both was simulated.

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Background: During peroral esophageal myotomy (POEM) for the treatment of achalasia, the optimal distal gastric myotomy length is unknown. In this study, we used a functional lumen imaging probe (FLIP) to intraoperatively measure the effect of variable distal myotomy lengths on esophagogastric junction (EGJ) distensibility.

Methods: EGJ distensibility index (DI) (minimum cross-sectional area divided by intrabag pressure) was measured with FLIP after each operative step.

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Objectives: Enhanced characterization of esophageal peristaltic and sphincter function provided by esophageal pressure topography (EPT) offers a potential diagnostic advantage over conventional line tracings (CLT). However, high-resolution manometry (HRM) and EPT require increased equipment costs over conventional systems and evidence demonstrating a significant diagnostic advantage of EPT over CLT is limited. Our aim was to investigate whether the inter-rater agreement and/or accuracy of esophageal motility diagnosis differed between EPT and CLT.

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Importance: Achalasia significantly affects patients' quality of life and can be difficult to diagnose and treat.

Objective: To review the diagnosis and management of achalasia, with a focus on phenotypic classification pertinent to therapeutic outcomes.

Evidence Review: Literature review and MEDLINE search of articles from January 2004 to February 2015.

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Objectives: Adenoma-detection rates (ADRs) are associated with decreased interval colorectal cancer (CRC) rates and CRC mortality; quality improvement strategies focus on improving physician ADRs. The objective of this study was to examine the sequential effect of physician report cards and implementing institutional standards of practice (SOP) on ADRs.

Methods: Colonoscopy metrics were prospectively evaluated at a single academic medical center over a 23-month period (November 2012 to October 2014).

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Background & Aims: High-resolution manometry (HRM) expands recognition of minor esophageal motor abnormalities, but the clinical significance of these is unclear. We aimed to determine the outcomes of minor esophageal motor abnormalities.

Methods: We reviewed HRM tracings from patients who underwent esophageal manometry at Northwestern Memorial Hospital from July 2004 through October 2005 by using the Chicago classification (version 2.

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Introduction. Proton pump inhibitors (PPI) are one of the most commonly prescribed medication classes with similar efficacy between brand name and generic PPI formulations. Aims.

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Symptoms of heartburn and dysphagia as well as objective findings of abnormal esophageal acid exposure and esophageal dysmotility are common in patients with systemic sclerosis (SSc). Treatments for SSc esophageal disease are generally limited to gastroesophageal reflux disease (GERD) treatment with proton pump inhibitors. Progresses made in esophageal diagnostic testing offer the potential for improved clinical characterization of esophageal disease in SSc that may help direct management decisions.

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Background & Aims: Gastroesophageal reflux disease (GERD) is a common and costly disorder. Symptoms attributed to GERD have a wide spectrum of presentations and complications that have led to complex diagnostic and management algorithms. As such, there is considerable variation in clinical approaches to GERD.

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Background: The γ-aminobutyric acid type B-receptor agonist lesogaberan (AZD3355) has been developed for use in patients with gastroesophageal reflux disease (GERD) symptoms despite proton pump inhibitor (PPI) therapy (partial responders). This study aimed to explore the dose-response effect of lesogaberan on reflux episodes in partial responders.

Methods: In this randomized, single-centre, double-blind, crossover, placebo-controlled study, partial responders taking optimised PPI therapy were given 30, 90, 120 and 240 mg doses of lesogaberan.

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The Chicago Classification defines esophageal motility disorders in high resolution manometry. This is based on individual scoring of 10 swallows performed in supine position. Disorders of esophago-gastric junction (EGJ) outflow obstruction are defined by a median integrated relaxation pressure above the limit of normal and divided into 3 achalasia subtypes and EGJ outflow obstruction.

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Background: The functional lumen imaging probe (FLIP) is a novel diagnostic tool that can be used to measure esophagogastric junction (EGJ) distensibility. In this study, we performed intraoperative FLIP measurements during laparoscopic Heller myotomy (LHM) and peroral esophageal myotomy (POEM) for treatment of achalasia and evaluated the relationship between EGJ distensibility and postoperative symptoms.

Methods: Distensibility index (DI) (defined as the minimum cross-sectional area at the EGJ divided by distensive pressure) was measured with FLIP at two time points during LHM and POEM: (1) at baseline after induction of anesthesia, and (2) after operation completion.

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We aimed to model esophageal bolus transit based on esophageal pressure topography (EPT) landmarks, concurrent intrabolus pressure (IBP), and esophageal diameter as defined with fluoroscopy. Ten healthy subjects were studied with high-resolution impedance manometry and videofluoroscopy. Data from four 5-ml barium swallows (2 upright, 2 supine) in each subject were analyzed.

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Background: Peroral esophageal myotomy (POEM) is a new endoscopic operation for the treatment of achalasia. Here, we report 1-year physiologic and symptomatic outcomes following the procedure.

Methods: POEM patients from a single-institution series who were more than 1 year removed from surgery were studied.

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Background: For laparoscopic Heller myotomy (LHM), the optimal myotomy length proximal to the esophagogastric junction (EGJ) is unknown. In this study, we used a functional lumen imaging probe (FLIP) to measure EGJ distensibility changes resulting from variable proximal myotomy lengths during LHM and peroral esophageal myotomy (POEM).

Methods: Distensibility index (DI) (defined as the minimum cross-sectional area at the EGJ divided by pressure) was measured with FLIP after each operative step.

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This study aimed to develop and validate a method to measure bolus flow time (BFT) through the esophagogastric junction (EGJ) using a high-resolution impedance-manometry (HRIM) sleeve. Ten healthy subjects were studied with concurrent HRIM and videofluoroscopy; another 15 controls were studied with HRIM alone. HRIM studies were performed using a 4.

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