Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017168 (gastroesophageal reflux disease)
 11,783 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Diagnostic interventions in nuclear medicine may be defined as the coadministration of a nonradioactive drug or application of a physical stimulus or physiologic maneuver to enhance the diagnostic utility of a nuclear medicine test. The rationale for each interventional maneuver follows from the physiology or metabolism of the particular organ or organ system under evaluation. Diagnostic inference is drawn from the pattern of change in the biodistribution of the tracer in response to the intervention-induced change in metabolism or function. In current practice, the most commonly performed interventional maneuvers are aimed at studies of the heart, genitourinary system, hepatobiliary system, and gastrointestinal tract. The single most commonly performed interventional study in the United States is the stress Thallium-201 myocardial perfusion scan aimed at the diagnosis of coronary artery disease. The stress portion of the study is accomplished with dynamic leg exercise on a treadmill and is aimed at increasing myocardial oxygen demands. Areas of myocardium distal to hemodynamically significant lesions in the coronary arteries become ischemic at peak stress due to the inability of the stenotic vessel to respond to the oxygen demand/blood flow needs of the myocardium. Ischemic areas are readily recognized as photopenic defects on scans obtained immediately after exercise, with "normalization" upon delayed imaging. Diuresis renography is aimed at the differential diagnosis of hydroureteronephrosis. By challenging the urinary tract collecting structures with an augmented urine flow, dilated, unobstructed systems can be differentiated from systems with significant mechanical obstruction. Obstructed systems have a low ability to respond even after effective diuresis, resulting in a characteristic prolonged retention of the radiotracer. Hepatobiliary interventions are most commonly employed in the clinical setting of suspected acute cholecystitis. Administering a cholecystogogue before a hepatobiliary tracer promotes visualization of the gallbladder by causing it to go through a contraction/filling cycle in which the filling phase occurs during maximum exposure to the radionuclide. This maneuver can convert a false positive study that suggests the presence of acute cholecystitis to a true negative study. Other gastrointestinal interventions are aimed at enhancing the detection of gastroesophageal reflux and gastrointestinal bleeding. Many new interventions have been developed that are currently aimed at research problems rather than clinical problems.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Diagnostic interventions in nuclear medicine. 264 73

A variety of scintigraphic techniques has been added to the gastroenterologist's armamentarium for the evaluation of motor dysfunction of the upper gastrointestinal tract and hepatobiliary tree. These methods include: esophageal transit scintigraphy for the measurement and quantitation of aboral movement of liquids through the esophagus, and for the measurement of esophageal clearance; gastroesophageal reflux scintigraphy for the detection and quantitation of gastroesophageal reflux, gastric scintigraphy for the physiological measurement of the simultaneous rates of emptying of liquids and solids from the stomach; hepatobiliary scintigraphy for the detection of acute cholecystitis, biliary tract obstruction, bile leaks; and enterogastric reflux scintigraphy for the detection and quantitation of bile reflux from the small bowel into the stomach. Each of these methods is relatively physiologic in comparison to other modalities in that none requires intubation or other nonphysiologic maneuvers. Each offers the practicing internist, surgeon, and gastrointestinal physiologist, the ability to measure normal and abnormal function in patients. Because of the low radiation burdens involved and high patient acceptance, these methods are suitable for serial studies in the same patient, particularly before and after the application of various therapeutic modalities.
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PMID:Scintigraphic techniques for the study of gastrointestinal motor function. 351 25

Patients are often referred for evaluation of a wide range of GI complaints including dysphagia, abdominal pain, bloating, nausea, constipation or diarrhoea. Many are diagnosed with 'functional' disease when endoscopy or conventional radiological studies fail to identify an anatomic cause for the patient's symptoms. In such cases nuclear medicine offers non-invasive methods for objectively demonstrating disease involving different areas of the gastrointestinal tract. Increasingly scintigraphy is playing a primary role in the evaluation of patients with suspected acute cholecystitis, active gastrointestinal bleeding, gastroparesis, and small and large bowel motility disorders. In addition, it supplements other studies when results are inconclusive in diagnosing oesophageal dysmotility, gastro-oesophageal reflux, acalculous cholecystitis, and postoperative complications of gastrointestinal surgery.
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PMID:Current applicability of scintigraphic methods in gastroenterology. 777 16