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Dive into the research topics where Alan H. Maurer is active.

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Featured researches published by Alan H. Maurer.


The American Journal of Gastroenterology | 2008

Consensus recommendations for gastric emptying scintigraphy: A joint report of the American neurogastroenterology and motility society and the society of nuclear medicine

Thomas L. Abell; Michael Camilleri; Kevin J. Donohoe; William L. Hasler; Henry C. Lin; Alan H. Maurer; Richard W. McCallum; Thomas Nowak; Martin L. Nusynowitz; Henry P. Parkman; Paul Shreve; Lawrence A. Szarka; William J. Snape; Harvey A. Ziessman

This consensus statement from the members of the American Neurogastroenterology and Motility Society and the Society of Nuclear Medicine recommends a standardized method for measuring gastric emptying (GE) by scintigraphy. A low-fat, egg-white meal with imaging at 0, 1, 2, and 4 h after meal ingestion, as described by a published multicenter protocol, provides standardized information about normal and delayed GE. Adoption of this standardized protocol will resolve the lack of uniformity of testing, add reliability and credibility to the results, and improve the clinical utility of the GE test.


Neurogastroenterology and Motility | 2011

Evaluation of gastrointestinal transit in clinical practice: position paper of the American and European Neurogastroenterology and Motility Societies

Satish S. Rao; Michael Camilleri; William L. Hasler; Alan H. Maurer; Henry P. Parkman; R. Saad; M Scott; Magnus Simren; E. E. Soffer; Lawrence A. Szarka

Background  Disorders of gastrointestinal (GI) transit and motility are common, and cause either delayed or accelerated transit through the stomach, small intestine or colon, and affect one or more regions. Assessment of regional and/or whole gut transit times can provide direct measurements and diagnostic information to explain the cause of symptoms, and plan therapy.


Gastroenterology | 1988

Role of opiate receptors in the regulation of colonic transit

Peter N. Kaufman; Benjamin Krevsky; Leon S. Malmud; Alan H. Maurer; Marjorie B. Somers; Jeffrey A. Siegel; Robert S. Fisher

The effects of morphine and the opiate antagonist naloxone on human colonic transit were investigated. In a crossover, double-blind fashion, two groups of 6 normal volunteers were studied using colonic transit scintigraphy during the administration of a test drug or control. The test drugs were morphine (0.1 mg/kg every 6 h s.c.) or naloxone (0.8 mg every 6 h s.c.); control was saline (1 ml every 6 h s.c.). Morphine significantly delayed transit in the cecum and ascending colon (p less than 0.05), slowed the progression of the geometric center (p less than 0.01), and decreased the number of bowel movements per 48 h (p less than 0.005). Naloxone accelerated transit in the transverse colon and rectosigmoid colon (p less than 0.05) and accelerated the progression of the geometric center (p less than 0.05), but had no effect on the number of bowel movements per 48 h (p greater than 0.05). These results suggest that narcotic analgesics may cause constipation in part by slowing colonic transit in the proximal colon and by inhibiting defecation. Acceleration of transit by naloxone suggests that endogenous opiate peptides may play an inhibitory role in the regulation of human colonic transit.


Gastroenterology | 1986

Colonic Transit Scintigraphy: A Physiologic Approach to the Quantitative Measurement of Colonic Transit in Humans

Benjamin Krevsky; Leon S. Malmud; Francine D'Ercole; Alan H. Maurer; Robert S. Fisher

Colonic transit scintigraphy was developed to quantitatively evaluate colonic transit. Using this technique the progression of a radiolabeled marker from cecal instillation to defecation was studied in 7 normal male volunteers. An 8-ml bolus containing 50 mu Ci of indium 111-diethylene triamine pentaacetic acid was instilled into the cecum via a 2-mm tube, which was passed orally, and serial scintigrams were obtained over 48 h. By 48 h, 70.7% +/- 9.1% (mean +/- SEM) of the instilled activity had been defecated. The cecum and ascending colon emptied rapidly, with a half-emptying time of 87.6 +/- 27.0 min. Geometric center analysis showed an initial logarithmic progression of activity in the proximal colon and a linear progression distally. This study suggests that the transverse colon, not the cecum and ascending colon, may be the primary site for fecal storage. Colonic transit scintigraphy is a safe, physiologic, and quantitative method for evaluating the colonic transit of fecal material and may provide a useful tool for evaluating normal and abnormal large intestinal physiology.


Neurogastroenterology and Motility | 2008

Gastric emptying of a non-digestible solid: assessment with simultaneous SmartPill pH and pressure capsule, antroduodenal manometry, gastric emptying scintigraphy

D. Cassilly; Steven Kantor; Linda C. Knight; Alan H. Maurer; Robert S. Fisher; J. Semler; Henry P. Parkman

Abstract  Gastric emptying of digestible solids occurs after trituration of food particles. Non‐digestible solids are thought to empty with phase III of the migrating motor complex (MMC). The aim of this study was to determine if a non‐digestible capsule given with a meal empties from the stomach with return of the fasting phase III MMC or during the fed pattern with the solid meal. Fifteen normal subjects underwent antroduodenal manometry and ingestion of a radiolabelled meal and SmartPill wireless pH and pressure capsule. In five subjects, emptying of the SmartPill was studied in the fasting period by ingesting the SmartPill with radiolabelled water. The SmartPill emptied from the stomach within 6 h in 14 of 15 subjects. SmartPill pressure recordings showed high amplitude phasic contractions prior to emptying. SmartPill gastric residence time (261 ± 22 min) correlated strongly with time to the first phase III MMC (239 ± 23 min; r = 0.813; P < 0.01) and correlated moderately with solid‐phase gastric emptying (r = 0.606 with T‐50% and r = 0.565 with T‐90%). Nine of 14 subjects emptied the capsule with a phase III MMC. In five subjects, the SmartPill emptied with isolated distal antral contractions. In five subjects ingesting only water, SmartPill gastric residence time (92 ± 44 min) correlated with the time to the first phase III MMC (87 ± 30 min; r = 0.979; P < 0.01). The non‐digestible SmartPill given with a meal primarily empties from the stomach with the return of phase III MMCs occurring after emptying the solid‐phase meal. However, in some subjects, the SmartPill emptied with isolated antral contractions, an unappreciated mechanism for emptying of a non‐digestible solid.


The American Journal of Gastroenterology | 2002

Treatment of idiopathic gastroparesis with injection of botulinum toxin into the pyloric sphincter muscle.

Larry S. Miller; Gregory A. Szych; Steven Kantor; Matthew Q. Bromer; Linda C. Knight; Alan H. Maurer; Robert S. Fisher; Henry P. Parkman

OBJECTIVES:We aimed to determine if botulinum toxin injection into the pyloric sphincter improves gastric emptying and reduces symptoms in patients with idiopathic gastroparesis.METHODS:Patients with idiopathic gastroparesis not responding to prokinetic therapy underwent botulinum toxin (80–100 U, 20 U/ml) injection into the pyloric sphincter. Gastric emptying scintigraphy was performed before and 4 wk after treatment. Total symptom scores were obtained from the sum of eight upper GI symptoms graded on a scale from 0 (none) to 4 (extreme).RESULTS:Ten patients were entered into the study. The mean percentage of solid gastric retention at 4 h improved from 27 ± 6% (normal < 10%) before botulinum toxin injection into the pylorus to 14 ± 4% (p = 0.038) 4 wk after treatment. The symptom score decreased from 15.3 ± 1.7 at baseline to 9.0 ± 1.9 (p = 0.006) at 4 wk, a 38 ± 9% decrease. Improvement in symptoms tended to correlate with improved gastric emptying of solids (r = 0.565, p = 0.086).CONCLUSIONS:This initial pilot study suggests that botulinum toxin injection into the pylorus in patients with idiopathic gastroparesis improves both gastric emptying and symptoms.


Digestive Diseases and Sciences | 2001

Extending Gastric Emptying Scintigraphy from Two to Four Hours Detects More Patients with Gastroparesis

Jin-Ping Guo; Alan H. Maurer; Robert S. Fisher; Henry P. Parkman

Gastric emptying scintigraphy (GES) is usually performed for up to 2 hr to measure the gastric emptying (GE) of solids. Symptomatic patients, however, may have borderline results at 2 hr, making it difficult to determine whether a gastric motor disorder is present. The aim of this study was to assess whether extending GES to 4 hr is useful in evaluating patients for gastroparesis and to correlate the results of GES with patient symptoms. We studied 129 patients undergoing GES at Temple University Hospital between July 1998 and March 1999. Solid-phase GE was measured at 0, 0.5, 1, 2, 3, and 4 hr after ingestion of a 99mTc sulfur colloid-labeled egg meal. Dyspeptic symptoms of upper abdominal discomfort, early satiety, postprandial abdominal bloating, nausea, vomiting, and anorexia were graded as none, mild, moderate and severe (0, 1, 2 and 3, respectively) with the sum representing a total symptom score. Of 129 patients, 86 had normal GE at 2 hr; 26 of the 86 normal scans at 2 hr were delayed at 3 hr. Six of the 60 scans normal at 2 and 3 hr were delayed at 4 hr. Of 43 patients with delayed GE at 2 hr, 39 were delayed at 3 hr and 35 were delayed at 4 hr. Overall, the percentage of patients with delayed GE increased from 33% at 2 hr only to 58% using the results of the 2-, 3-, and 4-hr scans (P < 0.05). There was a significantly greater symptom score in patients with delayed GE compared to patients with normal GE (8.4 ± 0.5 vs 7.1 ± 0.5; P < 0.05). Conclusion, prolonging GES after ingestion of a 99mTc-labeled egg meal from 2 to 4 hr increased the number of symptomatic patients found to have delayed GE. These results suggest that GES should be performed for up to 4 hrs when the 2-hr result is normal.


American Journal of Cardiology | 1984

Coronary thrombolysis by intravenous streptokinase in acute myocardial infarction: Acute and follow-up studies

James F. Spann; Sol Sherry; Blase A. Carabello; Barry S. Denenberg; Richard H. Mann; William D. McCann; James H. Gault; Richard D. Gentzler; Arthur D. Belber; Alan H. Maurer; Emmett M. Cooper

Coronary arteriography was performed before, immediately after, and 9 to 14 days after administering i.v. streptokinase (850,000 to 1,500,000 IU) to 43 patients within 6 hours of myocardial infarction. Ventricular function was determined by contrast ventriculography before and 9 to 14 days later and by radionuclide studies at clinical follow-up 8 months later. Early reperfusion occurred in 49% of patients, but in only 35% was it sustained. In patients with sustained reperfusion, early ventricular dysfunction was significantly reduced 9 to 14 days and 10 months later, and frequency of infarction, sudden death, and angina pectoris was not increased at follow-up. No serious bleeding occurred.


Journal of Nuclear Medicine Technology | 2008

Consensus Recommendations for Gastric Emptying Scintigraphy: A Joint Report of the American Neurogastroenterology and Motility Society and the Society of Nuclear Medicine

Thomas L. Abell; Michael Camilleri; Kevin J. Donohoe; William L. Hasler; Henry C. Lin; Alan H. Maurer; Richard W. McCallum; Thomas Nowak; Martin L. Nusynowitz; Henry P. Parkman; Paul Shreve; Lawrence A. Szarka; William J. Snape; Harvey A. Ziessman

This consensus statement from the members of the American Neurogastroenterology and Motility Society and the Society of Nuclear Medicine recommends a standardized method for measuring gastric emptying (GE) by scintigraphy. A low-fat, egg-white meal with imaging at 0, 1, 2, and 4 h after meal ingestion, as described by a published multicenter protocol, provides standardized information about normal and delayed GE. Adoption of this standardized protocol will resolve the lack of uniformity of testing, add reliability and credibility to the results, and improve the clinical utility of the GE test.


The American Journal of Gastroenterology | 2000

Whole gut transit scintigraphy in the clinical evaluation of patients with upper and lower gastrointestinal symptoms

Eugene S. Bonapace; Alan H. Maurer; Scott Davidoff; Benjamin Krevsky; Robert S. Fisher; Henry P. Parkman

OBJECTIVE:In a single noninvasive, quantitative test, whole gut transit scintigraphy (WGTS) measures gastric emptying (GE), small bowel transit (SBT), and colonic transit (CT). The aim of this study was to investigate the clinical utility of WGTS in patients with functional gastrointestinal (GI) symptoms.METHODS:A total of 108 patients with either dyspeptic upper GI symptoms (n = 35) or constipation (n = 73) underwent WGTS. Patients consumed a meal of 99 m-Tc egg sandwich with 111-In DTPA in water. They were imaged every 30 min for 6 h to measure GE and SBT, and at 24, 48, and 72 h to measure CT.RESULTS:Of 108 studies, 104 were analyzable. In patients with upper GI symptoms, 14/35 (40%) had delayed GE of solids, 4/35 (11%) delayed SBT, and 11/35 (31%) delayed CT. Of those with constipation, 13/69 (19%) had delayed GE, 5/69 (7%) delayed SBT, and 43/69 (65%) delayed CT. WGTS changed the initial clinical diagnosis in 47/104 (45%) and altered patient management in 70/104 (67%) of the patients.CONCLUSIONS:Transit abnormalities of the upper GI tract and colon are common in patients with functional GI symptoms. Patients with upper GI symptoms frequently have delayed GE, whereas those with constipation tend to have predominantly delayed CT. In many patients with functional GI symptoms, there was evidence of a diffuse GI motility disorder. Whole gut transit scintigraphy is a simple, clinically useful test, as it frequently leads to a change in diagnosis and, therefore, patient management.

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Richard W. McCallum

Texas Tech University Health Sciences Center

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