PubMed Health⌕ Search

Biomedical subjects

T R DeMeester

Publications and source records attributed to T R DeMeester.

At least 73 records · Page 4Linked to original sources
PubMed1998

Pharyngeal swallowing disorders: selection for and outcome after myotomy.

OBJECTIVE: To develop selection criteria based on the mechanical properties of pharyngoesophageal swallowing that indicate when patients with pharyngeal dysphagia will benefit from a myotomy. SUMMARY BACKGROUND DATA: The pathophysiology of pharyngoesophageal swallowing disorders is complex. The disorder is of interest to several medical specialists (gastroenterologists, otorhinolaryngologists, general and thoracic surgeons), which contributes to confusion about the entity. The management is compounded because it is most frequently seen in the elderly, is often associated with generalized neuromuscular disease, and occurs with a high prevalence of concomitant disease. The selection of patients for myotomy is difficult and of major importance to the quality of life of the affected patients. METHOD: One hundred seven patients without a Zenker diverticulum but with pharyngeal dysphagia underwent a detailed manometric assessment of the upper esophageal sphincter (UES). Cricopharyngeal opening was identified by the presence of a subatmospheric pressure drop before bolus arrival. Impaired pharyngoesophageal segment compliance resulting in a resistance to pharyngoesophageal flow was determined by measuring the intrabolus pressure generated by a 5-ml liquid bolus. RESULTS: Thirty-one of 107 patients underwent a myotomy (29%). Both impaired sphincter opening and increased intrabolus pressure predicted a good outcome. CONCLUSION: Myotomy is beneficial in patients with pharyngeal swallowing disorders and manometric evidence of defective sphincter opening and increased intrabolus pressure.

Adult↗
PubMed1998

Normal esophageal body function: a study using ambulatory esophageal manometry.

OBJECTIVE: The objective of this study was to establish normative ambulatory manometric data for contractions and contraction propagation in three levels of the esophagus. METHODS: Twenty-five healthy volunteers underwent simultaneous ambulatory 24 h manometry. Concomitant 24 h pH studies were performed to exclude the presence of increased esophageal acid exposure. Pressures were recorded over a complete circadian cycle while patients continued with their normal lifestyles including eating and sleeping. Data were analyzed with a software program that was previously modified and validated and that enables quantitation of contractions in terms of efficacy. RESULTS: The frequency of contractions was lowest during sleep, was increased when awake, and was highest during meals. Contraction amplitude increased during meals, providing a greater propulsive force for bolus transport. Similarly, the prevalence of peristaltic waves varied according to different physiologic states, ie., while eating, upright, awake, and sleeping. An increased amplitude and prevalence of peristalsis resulted in an increase in manometric efficacy during meals. CONCLUSIONS: This study provides normative data for ambulatory manometry for comparison when studying patients with disease.

Adult↗
PubMed1997

Nissen fundoplication prevents shortening of the sphincter during gastric distention.

OBJECTIVE: To determine the dynamic effects of a Nissen fundoplication on a volume-stressed lower esophageal sphincter (LES). DESIGN: Before and after experimental study in 10 baboons. SETTING: University animal research unit. INTERVENTIONS: Continuous manometric evaluation of the esophagus, cardia, and stomach during distention of the stomach with water. Slow motorized pull-through of the LES after each successive intragastric increment of 50 mL of water. Tests were performed again after a Nissen fundoplication. MAIN OUTCOME MEASURES: Lower esophageal sphincter length and frequency of common cavity episodes after each volume increment. The pressure and intragastric volume at the yield point are defined as the point of permanent loss of the gastroesophageal pressure gradient. RESULTS: Gastric distention of the stomach with water resulted in a progressive decrease in LES length and competency. The median +/- interquartile range LES length decreased by 1.5 +/- 0.3 mm for every 1-mm Hg increase in gastric pressure before fundoplication and by 0.2 +/- 0.1 mm after fundoplication (P < .02). With gastric distention there was an indirect correlation between the degree of LES length and the frequency of reflux episodes (r = -0.70). This correlation was abolished by a Nissen fundoplication (r = -0.31). The median +/- interquartile range frequency of common cavity episodes (2.19 +/- 2.05 episodes per minute) before fundoplication decreased significantly (P < .001) to 0 +/- 0.59 episodes per minute after fundoplication. The median +/- interquartile range yield pressure (13 +/- 9 mm Hg) and yield volume (825 +/- 855 mL) were significantly (P < .01) improved after Nissen fundoplication to 39 +/- 36 mm Hg and 1250 +/- 750 mL, respectively. CONCLUSION: By preventing sphincter shortening, a Nissen fundoplication improves competency of the LES to progressive degrees of gastric distention.

Animals↗
PubMed1997

A new intraluminal antigastroesophageal reflux procedure in baboons.

BACKGROUND: A new endoscopic intraluminal procedure (valvuloplasty) was designed to provide a simple, easy approach to the cardia and to correct and augment any mechanical deficiencies present. The feasibility, durability, and efficacy of this procedure was tested in 13 baboons. METHODS: The valvuloplasty consisted of an intussusception of the gastroesophageal junction into the stomach to create a nipple-type valve. The configuration of the valve was maintained with eight staples and stability was aided by an intramural injection of sodium morrhuate. Gastrointestinal endoscopy and esophageal manometry were performed before and after the procedure. Competency was determined as the intragastric pressure (yield pressure) and volume (yield volume) needed to result in equalization of gastric and esophageal pressure while distending the stomach with water. Comparisons were made with a group of normal baboons (n = 10). RESULTS: All baboons had a normal eating pattern with none showing any evidence of vomiting or regurgitation. Endoscopic circumferential integrity of the valves was 86% at 6 months. The median lower esophageal sphincter length in the valvuloplasty group was significantly (p < 0.01) increased after the procedure from 21 mm to 30 mm. The median yield pressure (22.1 mm Hg) and yield volume (1,525 ml) of the valvuloplasty group was significantly (p < 0.01) greater than the controls (14 mm Hg and 859 ml). CONCLUSIONS: The valvuloplasty is simple, safe, and durable. It augments mechanical function of the cardia and improves competency.

Animals↗
PubMed1997

Isolated upright gastroesophageal reflux is not a contraindication for antireflux surgery.

BACKGROUND: Patients with gastroesophageal reflux disease who reflux only in the upright position are thought to have a less severe abnormality. Controversy exists over whether these patients should be considered candidates for antireflux surgery. METHODS: A total of 224 consecutive patients with increased esophageal acid exposure on 24-hour pH monitoring were classified as having upright (n = 54), supine (n = 72), or bipositional (n = 98) reflux and were evaluated by manometry and endoscopy. Of these, 116 patients had a laparoscopic Nissen fundoplication. Their clinical outcome at a median of 12 months (range 4 to 44 months) was compared. RESULTS: Patients with upright reflux had a lower prevalence of a structurally defective lower esophageal sphincter, fewer hiatal hernias, and less esophageal injury when compared to those with bipositional reflux (p < 0.005). Excellent (asymptomatic) or good outcome (minor symptoms not requiring acid suppression therapy) was achieved in 86% of the patients with upright reflux, 90% of those with supine reflux, and 89% of those with bipositional reflux. CONCLUSIONS: Patients with upright reflux have less complicated, earlier disease and have results equivalent to those patients with supine and bipositional reflux after antireflux surgery.

Adolescent↗
PubMed1997

Composition and concentration of bile acid reflux into the esophagus of patients with gastroesophageal reflux disease.

BACKGROUND: Reflux of duodenal contents into the esophagus of patients with gastroesophageal reflux disease has been suggested by pH and bilirubin monitoring but is rarely directly measured. A portable device has been developed and was used to collect and quantitate material refluxed into the esophagus under ambulatory conditions during a prolonged time period. The objective of this study was to use this device to quantitate the composition and concentration of bile acids refluxed into the esophagus of patients with gastroesophageal reflux disease. METHODS: Esophageal aspiration was performed on 43 normal subjects and 37 patients with reflux disease during a 17-hour period. Aspiration was performed through a modified 16F Salem sump tube, positioned 5 cm above the lower esophageal sphincter and connected to a portable, battery powered pump that aspirated continuously at 100 mm Hg pressure. Validation studies showed that minimal amounts of saliva and swallowed liquids were aspirated and that gastric pressure was not altered. Postprandial, upright, and supine collections were performed. Total bile acids were assayed by a standard enzymatic assay; specific conjugated bile acids were analyzed by high-performance liquid chromatography. RESULTS: There was no difference in the total aspiration volume between normal volunteers and patients with gastroesophageal reflux disease, although patients tended to have a higher volume in the supine and postprandial periods. Bile acids could be detected in 58% of normal subjects and 86% of patients (p < 0.003). The mean concentration of bile salt exposure (micromole per liter) was higher in patients during the postprandial and supine periods. The mean bile acid reflux rate (micromole per hour) during all three aspiration periods was significantly higher in patients. On a molar basis the composition of the bile acids was 60% glycocholic acid, 16% glycodeoxycholic acid, and 15% glycochenodeoxycholic acid. Taurocholic, taurodeoxycholic, taurochenodeoxycholic, and glycolithocholic acid constituted the remaining 10%. CONCLUSIONS: Patients with reflux disease have an increased concentration of bile acids in their esophageal aspirates. Most of the exposure occurs during the postprandial and supine periods. A variety of bile acids were detected, most of which were in their glycine conjugated form.

Adult↗
PubMed1997

Esophageal replacement for end-stage benign esophageal disease.

The fact that esophageal resection and foregut reconstruction for benign disease can be performed with only a 2% mortality and minimal morbidity is encouraging news to patients who are crippled by the various manifestations of end-stage disease. The continuation of slow, anxious, and socially restricted alimentation or the maintenance of nutrition by enteral or parenteral means is unnecessary. The patient should be referred to a unit skilled in evaluating foregut function, performing esophageal replacement surgery, and caring for patients in the perioperative period. In our experience, the colon, when available, is the preferred conduit for esophageal replacement over the long term. Even though some subtle preoperative symptoms of foregut dysfunction may persist after surgery, the overall outcome is generally judged to be satisfactory. Indeed, patients can re-enter society and live a normal and fulfilled life after remedial surgery. Prolonged attempts at medical management of patients with severe derangements of esophageal structure and function are not warranted. Long-term esophageal replacement for severe end-stage benign disease can be accomplished with low mortality, a high degree of success, and a marked improvement in the quality of alimentation. Reconstruction restores the pleasure of eating and is viewed by the patient to be highly successful.

Colon↗
PubMed1997

Surgical treatment of dysplasia and adenocarcinoma.

It is currently recommended that patients with Barrett's esophagus who are medically fit be enrolled in a surveillance program and undergo 1 to 2 yearly endoscopy examinations with multiple biopsies. An acceptable protocol for these purposes requires obtaining four biopsy specimens, one from each quadrant of the esophagus, every 2 cm along the visible length of the Barrett's mucosa, with additional biopsy specimens from any abnormal-appearing area. Patients in surveillance programs are directed for further therapy if they develop low-grade or high-grade dysplasia or invasive adenocarcinoma.

Adenocarcinoma↗
PubMed1997

Gastroesophageal reflux in achalasia. When is reflux really reflux?

An abnormal score during 24-hr esophageal pH monitoring in achalasia may be associated either with a slow steady drift to below pH 4, or else multiple sharp dips characteristic of typical gastroesophageal reflux. To test the hypothesis that the former pattern was due to food fermentation and not reflux, samples of chewed bland food (N = 22) were incubated with saliva at 37 degrees C for 24 hr and the pH monitored (in vitro study). Further, the pH tracings of 20 patients with achalasia before operation and 12 patients after operation were studied (in vivo study). The pH of chewed food fell to a median of pH 4.0 during incubation and in seven of 22 samples fell to below pH 4. Preoperatively, four of the five patients with an abnormal pH score showed a slow steady drift, and all of these had evidence of retained food at endoscopy. Postoperatively, three of the six patients with an abnormal pH score had a slow steady drift to below pH 4. Use of pH 3 as a threshold clearly distinguished true reflux from food fermentation, since the patients with reflux all had an abnormal percentage of time below pH 3.

Esophageal Achalasia↗
PubMed1997

Barrett's esophagus. The significance of p53 in clinical practice.

OBJECTIVE: The authors provide an updated review the molecular biology of the p53 tumor suppressor gene with reference to its role in the malignant degeneration of Barrett's esophagus. SUMMARY BACKGROUND DATA: Appreciation of the function of the tumor suppressor gene p53 has given new insight into regulation of the cell cycle, and the gene appears to play an important role in many solid tumors. Esophageal adenocarcinoma is increasing in frequency in the western world at an alarming rate and is unique because there is a clear metaplasia (Barrett's mucosa)/ dysplasia/carcinoma sequence. p53 malfunction arises as an early event in this carcinogenic process and has been demonstrated in patients with nondysplastic Barrett's metaplasia. The possible causes of p53 malfunction in this setting are discussed. The most reliable method for the detection of p53 mutations is DNA sequencing. p53 immunohistochemistry appears too insensitive to act as a reliable marker for the presence of a mutation and cannot be used as a reliable marker for the future development of cancer. CONCLUSIONS: High-grade dysplasia within Barrett's mucosa remains the best clinical predictor of adenocarcinoma. The mutational spectrum observed in these tumors should provide clues to their etiology.

Adenocarcinoma↗
PubMed1997

Inflammation and specialized intestinal metaplasia of cardiac mucosa is a manifestation of gastroesophageal reflux disease.

OBJECTIVE: The purpose of the study was to test the hypothesis that cardiac mucosa, carditis, and specialized intestinal metaplasia at an endoscopically normal-appearing cardia are manifestations of gastroesophageal reflux disease. SUMMARY BACKGROUND DATA: In the absence of esophageal mucosal injury, the diagnosis of gastroesophageal reflux disease currently rests on 24-hour pH monitoring. Histologic examination of the esophagus is not useful. The recent identification of specialized intestinal metaplasia at the cardia, along with the observation that it occurs in inflamed cardiac mucosa, led the authors to focus on the type and condition of the mucosa at the gastroesophageal junction and its relation to gastroesophageal reflux disease. METHODS: Three hundred thirty-four consecutive patients with symptoms of foregut disease, no evidence of columnar-lined esophagus, and no history of gastric or esophageal surgery were evaluated by 1) endoscopic biopsies above, at, and below the gastroesophageal junction; 2) esophageal motility; and 3) 24-hour esophageal pH monitoring. The patients were divided into groups depending on the histologic presence of cardiac epithelium with and without inflammation or associated intestinal metaplasia. Markers of gastroesophageal reflux disease were compared between groups (i.e., lower esophageal sphincter characteristics, esophageal acid exposure, the presence of endoscopic erosive esophagitis, and hiatal hernia). RESULTS: When cardiac epithelium was found, it was inflamed in 96% of the patients. The presence of cardiac epithelium and carditis was associated with deterioration of lower esophageal sphincter characteristics and increased esophageal acid exposure. Esophagitis occurred more commonly in patients with carditis whose sphincter, on manometry, was structurally defective. Specialized intestinal metaplasia at the cardia was only seen in inflamed cardiac mucosa, and its prevalence increased both with increasing acid exposure and with the presence of esophagitis. CONCLUSION: The findings of cardiac mucosa, carditis, and intestinal metaplasia in an endoscopically normal-appearing gastroesophageal junction are histologic indicators of gastroesophageal reflux disease. These findings may be among the earliest signs of gastroesophageal reflux and contribute to the authors understanding of the pathophysiology of the disease process.

Adolescent↗
PubMed1997

Management of adenocarcinoma arising in Barrett's esophagus.

Esophageal adenocarcinoma is a highly malignant tumor and, if not diagnosed at an early stage, carries a poor prognosis. Controversy exists over how to manage carcinoma of the esophagus confined to the mucosa and the extent of resection to cure disease that has extended beyond the mucosa. Similarly, there are differing opinions regarding the role of adjuvant chemotherapy and the efficacy of surgical resection for palliation. These issues are discussed as they pertain to the management of adenocarcinoma arising in Barrett's esophagus.

Adenocarcinoma↗
PubMed1997

Can the combination of symptoms and endoscopy confirm the presence of gastroesophageal reflux disease?

The aim of this study was to evaluate the accuracy of symptomatology and esophagogastroduodenoscopy (EGD) in the diagnosis of proven gastroesophageal reflux disease (GERD). We evaluated the symptoms and EGD findings of 100 consecutive patients presenting with symptoms suggestive of GERD. Patients' symptoms were scored at their first visit with a standardized symptom scoring system (grades 0-3). Grade 3 symptoms were the most severe. EGD findings were classified according to the modified Savary-Miller scale. Esophageal acid exposure was quantified using 24-hour esophageal pH monitoring; a positive composite score was considered evidence of GERD. Fifty-seven patients had positive pH scores, and 43 were negative. The combination of grade 2 or 3 heartburn and/or regurgitation with erosive esophagitis or Barrett's esophagus on EGD had a 97 per cent specificity and 64 per cent sensitivity for accurately diagnosing GERD. It is concluded that, in the presence of moderate to severe symptoms and endoscopic injury, the diagnosis of GERD can be made without further studies. However, 24-hour esophageal pH monitoring is still indicated in patients with mild typical symptoms, atypical symptoms, or when the combination of heartburn and regurgitation, regardless of their severity, occurs in the absence of severe mucosal damage.

Adolescent↗
PubMed1997

Role of esophageal body function in gastroesophageal reflux disease: implications for surgical management.

BACKGROUND: Effective esophageal peristalsis is a major determinant of esophageal clearance function. The relation of esophageal body function with a mechanically defective lower esophageal sphincter and the development of esophageal mucosal injury in patients with gastroesophageal reflux disease is unclear. STUDY DESIGN: We analyzed the relations among the manometrically determined esophageal clearance function, lower esophageal sphincter dysfunction, esophageal acid exposure, and the presence and severity of esophageal mucosal injury in patients with gastroesophageal reflux disease. Normal values for the manometric assessment of esophageal clearance function were established in 50 normal volunteers and subsequently applied to 160 symptomatic patients with increased esophageal exposure to gastric juice and various grades of esophageal mucosal injury (no minimal surgery, esophagitis, stricture, and Barrett's esophagus). RESULTS: Defective clearance function was present in 47.5% of the patients; a defective lower esophageal sphincter was documented in 63.1%. Compromised esophageal clearance function was significantly more common in patients with a defective lower esophageal sphincter than in those with normal sphincter function (55% versus 33.8%). Esophageal acid exposure time and the prevalence and severity of esophageal mucosal injury were highest in patients with a defective sphincter and compromised clearance function. CONCLUSIONS: These data show that esophageal motor function deteriorates with increasing severity of mucosal injury. This appears to be due to persistent reflux of gastric juice across a mechanically defective lower esophageal sphincter. This may influence the choice and outcome of antireflux surgery. Surgical correction of a mechanically defective sphincter before the loss of esophageal body function is advocated.

Esophagus↗