Tomography, Emission-Computed, Single-Photon: A method of computed tomography that uses radionuclides which emit a single photon of a given energy. The camera is rotated 180 or 360 degrees around the patient to capture images at multiple positions along the arc. The computer is then used to reconstruct the transaxial, sagittal, and coronal images from the 3-dimensional distribution of radionuclides in the organ. The advantages of SPECT are that it can be used to observe biochemical and physiological processes as well as size and volume of the organ. The disadvantage is that, unlike positron-emission tomography where the positron-electron annihilation results in the emission of 2 photons at 180 degrees from each other, SPECT requires physical collimation to line up the photons, which results in the loss of many available photons and hence degrades the image.Photons: Discrete concentrations of energy, apparently massless elementary particles, that move at the speed of light. They are the unit or quantum of electromagnetic radiation. Photons are emitted when electrons move from one energy state to another. (From Hawley's Condensed Chemical Dictionary, 11th ed)Organotechnetium Compounds: Organic compounds that contain technetium as an integral part of the molecule. These compounds are often used as radionuclide imaging agents.Tomography, X-Ray Computed: Tomography using x-ray transmission and a computer algorithm to reconstruct the image.Tomography, Emission-Computed: Tomography using radioactive emissions from injected RADIONUCLIDES and computer ALGORITHMS to reconstruct an image.Technetium Tc 99m Exametazime: A gamma-emitting RADIONUCLIDE IMAGING agent used in the evaluation of regional cerebral blood flow and in non-invasive dynamic biodistribution studies and MYOCARDIAL PERFUSION IMAGING. It has also been used to label leukocytes in the investigation of INFLAMMATORY BOWEL DISEASES.Oximes: Compounds that contain the radical R2C=N.OH derived from condensation of ALDEHYDES or KETONES with HYDROXYLAMINE. Members of this group are CHOLINESTERASE REACTIVATORS.Thallium Radioisotopes: Unstable isotopes of thallium that decay or disintegrate emitting radiation. Tl atoms with atomic weights 198-202, 204, and 206-210 are thallium radioisotopes.Radiopharmaceuticals: Compounds that are used in medicine as sources of radiation for radiotherapy and for diagnostic purposes. They have numerous uses in research and industry. (Martindale, The Extra Pharmacopoeia, 30th ed, p1161)Positron-Emission Tomography: An imaging technique using compounds labelled with short-lived positron-emitting radionuclides (such as carbon-11, nitrogen-13, oxygen-15 and fluorine-18) to measure cell metabolism. It has been useful in study of soft tissues such as CANCER; CARDIOVASCULAR SYSTEM; and brain. SINGLE-PHOTON EMISSION-COMPUTED TOMOGRAPHY is closely related to positron emission tomography, but uses isotopes with longer half-lives and resolution is lower.Iofetamine: An amphetamine analog that is rapidly taken up by the lungs and from there redistributed primarily to the brain and liver. It is used in brain radionuclide scanning with I-123.Technetium: The first artificially produced element and a radioactive fission product of URANIUM. Technetium has the atomic symbol Tc, atomic number 43, and atomic weight 98.91. All technetium isotopes are radioactive. Technetium 99m (m=metastable) which is the decay product of Molybdenum 99, has a half-life of about 6 hours and is used diagnostically as a radioactive imaging agent. Technetium 99 which is a decay product of technetium 99m, has a half-life of 210,000 years.Iodine Radioisotopes: Unstable isotopes of iodine that decay or disintegrate emitting radiation. I atoms with atomic weights 117-139, except I 127, are radioactive iodine isotopes.ComputersCerebrovascular Circulation: The circulation of blood through the BLOOD VESSELS of the BRAIN.IodobenzenesTechnetium Tc 99m Sestamibi: A technetium imaging agent used to reveal blood-starved cardiac tissue during a heart attack.Thallium: A heavy, bluish white metal, atomic number 81, atomic weight [204.382; 204.385], symbol Tl.Xenon Radioisotopes: Unstable isotopes of xenon that decay or disintegrate emitting radiation. Xe atoms with atomic weights 121-123, 125, 127, 133, 135, 137-145 are radioactive xenon isotopes.Technetium Tc 99m Pyrophosphate: A radionuclide imaging agent used primarily in scintigraphy or tomography of the heart to evaluate the extent of the necrotic myocardial process. It has also been used in noninvasive tests for the distribution of organ involvement in different types of amyloidosis and for the evaluation of muscle necrosis in the extremities.Heart: The hollow, muscular organ that maintains the circulation of the blood.Brain: The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.Tropanes: N-methyl-8-azabicyclo[3.2.1]octanes best known for the ones found in PLANTS.Amphetamines: Analogs or derivatives of AMPHETAMINE. Many are sympathomimetics and central nervous system stimulators causing excitation, vasopressin, bronchodilation, and to varying degrees, anorexia, analepsis, nasal decongestion, and some smooth muscle relaxation.Magnetic Resonance Imaging: Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography: Tomography using single-photon emitting RADIONUCLIDES to create images that are captured in times corresponding to various points in the cardiac cycle.Sensitivity and Specificity: Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)Tomography: Imaging methods that result in sharp images of objects located on a chosen plane and blurred images located above or below the plane.Myocardial Perfusion Imaging: The creation and display of functional images showing where the blood is flowing into the MYOCARDIUM by following over time the distribution of tracers injected into the blood stream.Diagnostic Imaging: Any visual display of structural or functional patterns of organs or tissues for diagnostic evaluation. It includes measuring physiologic and metabolic responses to physical and chemical stimuli, as well as ultramicroscopy.Acetazolamide: One of the CARBONIC ANHYDRASE INHIBITORS that is sometimes effective against absence seizures. It is sometimes useful also as an adjunct in the treatment of tonic-clonic, myoclonic, and atonic seizures, particularly in women whose seizures occur or are exacerbated at specific times in the menstrual cycle. However, its usefulness is transient often because of rapid development of tolerance. Its antiepileptic effect may be due to its inhibitory effect on brain carbonic anhydrase, which leads to an increased transneuronal chloride gradient, increased chloride current, and increased inhibition. (From Smith and Reynard, Textbook of Pharmacology, 1991, p337)Image Processing, Computer-Assisted: A technique of inputting two-dimensional images into a computer and then enhancing or analyzing the imagery into a form that is more useful to the human observer.Organophosphorus Compounds: Organic compounds that contain phosphorus as an integral part of the molecule. Included under this heading is broad array of synthetic compounds that are used as PESTICIDES and DRUGS.Computer Simulation: Computer-based representation of physical systems and phenomena such as chemical processes.Exercise Test: Controlled physical activity which is performed in order to allow assessment of physiological functions, particularly cardiovascular and pulmonary, but also aerobic capacity. Maximal (most intense) exercise is usually required but submaximal exercise is also used.Phantoms, Imaging: Devices or objects in various imaging techniques used to visualize or enhance visualization by simulating conditions encountered in the procedure. Phantoms are used very often in procedures employing or measuring x-irradiation or radioactive material to evaluate performance. Phantoms often have properties similar to human tissue. Water demonstrates absorbing properties similar to normal tissue, hence water-filled phantoms are used to map radiation levels. Phantoms are used also as teaching aids to simulate real conditions with x-ray or ultrasonic machines. (From Iturralde, Dictionary and Handbook of Nuclear Medicine and Clinical Imaging, 1990)Cinanserin: A serotonin antagonist with limited antihistaminic, anticholinergic, and immunosuppressive activity.Organometallic Compounds: A class of compounds of the type R-M, where a C atom is joined directly to any other element except H, C, N, O, F, Cl, Br, I, or At. (Grant & Hackh's Chemical Dictionary, 5th ed)Multimodal Imaging: The use of combination of imaging techniques or platforms (e.g., MRI SCAN and PET SCAN) encompassing aspects of anatomical, functional, or molecular imaging methods.Myocytes, Cardiac: Striated muscle cells found in the heart. They are derived from cardiac myoblasts (MYOBLASTS, CARDIAC).Fluorodeoxyglucose F18: The compound is given by intravenous injection to do POSITRON-EMISSION TOMOGRAPHY for the assessment of cerebral and myocardial glucose metabolism in various physiological or pathological states including stroke and myocardial ischemia. It is also employed for the detection of malignant tumors including those of the brain, liver, and thyroid gland. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1162)Dopamine Plasma Membrane Transport Proteins: Sodium chloride-dependent neurotransmitter symporters located primarily on the PLASMA MEMBRANE of dopaminergic neurons. They remove DOPAMINE from the EXTRACELLULAR SPACE by high affinity reuptake into PRESYNAPTIC TERMINALS and are the target of DOPAMINE UPTAKE INHIBITORS.Predictive Value of Tests: In screening and diagnostic tests, the probability that a person with a positive test is a true positive (i.e., has the disease), is referred to as the predictive value of a positive test; whereas, the predictive value of a negative test is the probability that the person with a negative test does not have the disease. Predictive value is related to the sensitivity and specificity of the test.Indium Radioisotopes: Unstable isotopes of indium that decay or disintegrate emitting radiation. In atoms with atomic weights 106-112, 113m, 114, and 116-124 are radioactive indium isotopes.Frontal Lobe: The part of the cerebral hemisphere anterior to the central sulcus, and anterior and superior to the lateral sulcus.Tomography, Optical Coherence: An imaging method using LASERS that is used for mapping subsurface structure. When a reflective site in the sample is at the same optical path length (coherence) as the reference mirror, the detector observes interference fringes.Thalamic Diseases: Disorders of the centrally located thalamus, which integrates a wide range of cortical and subcortical information. Manifestations include sensory loss, MOVEMENT DISORDERS; ATAXIA, pain syndromes, visual disorders, a variety of neuropsychological conditions, and COMA. Relatively common etiologies include CEREBROVASCULAR DISORDERS; CRANIOCEREBRAL TRAUMA; BRAIN NEOPLASMS; BRAIN HYPOXIA; INTRACRANIAL HEMORRHAGES; and infectious processes.Cerebral Revascularization: Microsurgical revascularization to improve intracranial circulation. It usually involves joining the extracranial circulation to the intracranial circulation but may include extracranial revascularization (e.g., subclavian-vertebral artery bypass, subclavian-external carotid artery bypass). It is performed by joining two arteries (direct anastomosis or use of graft) or by free autologous transplantation of highly vascularized tissue to the surface of the brain.Radioactive Tracers: Radioactive substances added in minute amounts to the reacting elements or compounds in a chemical process and traced through the process by appropriate detection methods, e.g., Geiger counter. Compounds containing tracers are often said to be tagged or labeled. (Hawley's Condensed Chemical Dictionary, 12th ed)Technetium Tc 99m Medronate: A gamma-emitting radionuclide imaging agent used primarily in skeletal scintigraphy. Because of its absorption by a variety of tumors, it is useful for the detection of neoplasms.Regional Blood Flow: The flow of BLOOD through or around an organ or region of the body.NortropanesRadioisotopes: Isotopes that exhibit radioactivity and undergo radioactive decay. (From Grant & Hackh's Chemical Dictionary, 5th ed & McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Time Factors: Elements of limited time intervals, contributing to particular results or situations.Myocardial Ischemia: A disorder of cardiac function caused by insufficient blood flow to the muscle tissue of the heart. The decreased blood flow may be due to narrowing of the coronary arteries (CORONARY ARTERY DISEASE), to obstruction by a thrombus (CORONARY THROMBOSIS), or less commonly, to diffuse narrowing of arterioles and other small vessels within the heart. Severe interruption of the blood supply to the myocardial tissue may result in necrosis of cardiac muscle (MYOCARDIAL INFARCTION).Spondylolysis: Deficient development or degeneration of a portion of the VERTEBRA, usually in the pars interarticularis (the bone bridge between the superior and inferior facet joints of the LUMBAR VERTEBRAE) leading to SPONDYLOLISTHESIS.Reproducibility of Results: The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.Tissue Survival: The span of viability of a tissue or an organ.Gamma Cameras: Electronic instruments that produce photographs or cathode-ray tube images of the gamma-ray emissions from organs containing radionuclide tracers.Dipyridamole: A phosphodiesterase inhibitor that blocks uptake and metabolism of adenosine by erythrocytes and vascular endothelial cells. Dipyridamole also potentiates the antiaggregating action of prostacyclin. (From AMA Drug Evaluations Annual, 1994, p752)Electrocardiography: Recording of the moment-to-moment electromotive forces of the HEART as projected onto various sites on the body's surface, delineated as a scalar function of time. The recording is monitored by a tracing on slow moving chart paper or by observing it on a cardioscope, which is a CATHODE RAY TUBE DISPLAY.Spectrometry, Gamma: Determination of the energy distribution of gamma rays emitted by nuclei. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Myocardial Infarction: NECROSIS of the MYOCARDIUM caused by an obstruction of the blood supply to the heart (CORONARY CIRCULATION).Technetium Tc 99m Aggregated Albumin: A gamma-emitting radionuclide imaging agent used for the diagnosis of diseases in many tissues, particularly in cardiovascular and cerebral circulation.Image Enhancement: Improvement of the quality of a picture by various techniques, including computer processing, digital filtering, echocardiographic techniques, light and ultrastructural MICROSCOPY, fluorescence spectrometry and microscopy, scintigraphy, and in vitro image processing at the molecular level.Coronary Angiography: Radiography of the vascular system of the heart muscle after injection of a contrast medium.Dominance, Cerebral: Dominance of one cerebral hemisphere over the other in cerebral functions.Molecular Imaging: The use of molecularly targeted imaging probes to localize and/or monitor biochemical and cellular processes via various imaging modalities that include RADIONUCLIDE IMAGING; ULTRASONOGRAPHY; MAGNETIC RESONANCE IMAGING; FLUORESCENCE IMAGING; and MICROSCOPY.Coronary Disease: An imbalance between myocardial functional requirements and the capacity of the CORONARY VESSELS to supply sufficient blood flow. It is a form of MYOCARDIAL ISCHEMIA (insufficient blood supply to the heart muscle) caused by a decreased capacity of the coronary vessels.Imaging, Three-Dimensional: The process of generating three-dimensional images by electronic, photographic, or other methods. For example, three-dimensional images can be generated by assembling multiple tomographic images with the aid of a computer, while photographic 3-D images (HOLOGRAPHY) can be made by exposing film to the interference pattern created when two laser light sources shine on an object.Coronary Circulation: The circulation of blood through the CORONARY VESSELS of the HEART.Radionuclide Imaging: The production of an image obtained by cameras that detect the radioactive emissions of an injected radionuclide as it has distributed differentially throughout tissues in the body. The image obtained from a moving detector is called a scan, while the image obtained from a stationary camera device is called a scintiphotograph.Flumazenil: A potent benzodiazepine receptor antagonist. Since it reverses the sedative and other actions of benzodiazepines, it has been suggested as an antidote to benzodiazepine overdoses.Tissue Distribution: Accumulation of a drug or chemical substance in various organs (including those not relevant to its pharmacologic or therapeutic action). This distribution depends on the blood flow or perfusion rate of the organ, the ability of the drug to penetrate organ membranes, tissue specificity, protein binding. The distribution is usually expressed as tissue to plasma ratios.Myocardium: The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.Cardiac Output: The volume of BLOOD passing through the HEART per unit of time. It is usually expressed as liters (volume) per minute so as not to be confused with STROKE VOLUME (volume per beat).Tomography, Optical: Projection of near-IR light (INFRARED RAYS), in the 700-1000 nm region, across an object in parallel beams to an array of sensitive photodetectors. This is repeated at various angles and a mathematical reconstruction provides three dimensional MEDICAL IMAGING of tissues. Based on the relative transparency of tissues to this spectra, it has been used to monitor local oxygenation, brain and joints.Echocardiography: Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues. The standard approach is transthoracic.Temporal Lobe: Lower lateral part of the cerebral hemisphere responsible for auditory, olfactory, and semantic processing. It is located inferior to the lateral fissure and anterior to the OCCIPITAL LOBE.Moyamoya Disease: A noninflammatory, progressive occlusion of the intracranial CAROTID ARTERIES and the formation of netlike collateral arteries arising from the CIRCLE OF WILLIS. Cerebral angiogram shows the puff-of-smoke (moyamoya) collaterals at the base of the brain. It is characterized by endothelial HYPERPLASIA and FIBROSIS with thickening of arterial walls. This disease primarily affects children but can also occur in adults.Models, Structural: A representation, generally small in scale, to show the structure, construction, or appearance of something. (From Random House Unabridged Dictionary, 2d ed)Nitrogen Radioisotopes: Unstable isotopes of nitrogen that decay or disintegrate emitting radiation. N atoms with atomic weights 12, 13, 16, 17, and 18 are radioactive nitrogen isotopes.Tomography, Spiral Computed: Computed tomography where there is continuous X-ray exposure to the patient while being transported in a spiral or helical pattern through the beam of irradiation. This provides improved three-dimensional contrast and spatial resolution compared to conventional computed tomography, where data is obtained and computed from individual sequential exposures.Nuclear Medicine: A specialty field of radiology concerned with diagnostic, therapeutic, and investigative use of radioactive compounds in a pharmaceutical form.Ventricular Dysfunction, Left: A condition in which the LEFT VENTRICLE of the heart was functionally impaired. This condition usually leads to HEART FAILURE; MYOCARDIAL INFARCTION; and other cardiovascular complications. Diagnosis is made by measuring the diminished ejection fraction and a depressed level of motility of the left ventricular wall.Skull Neoplasms: Neoplasms of the bony part of the skull.Image Interpretation, Computer-Assisted: Methods developed to aid in the interpretation of ultrasound, radiographic images, etc., for diagnosis of disease.Pyrrolidines3-Iodobenzylguanidine: A guanidine analog with specific affinity for tissues of the sympathetic nervous system and related tumors. The radiolabeled forms are used as antineoplastic agents and radioactive imaging agents. (Merck Index, 12th ed) MIBG serves as a neuron-blocking agent which has a strong affinity for, and retention in, the adrenal medulla and also inhibits ADP-ribosyltransferase.Algorithms: A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.Ventricular Function, Left: The hemodynamic and electrophysiological action of the left HEART VENTRICLE. Its measurement is an important aspect of the clinical evaluation of patients with heart disease to determine the effects of the disease on cardiac performance.Follow-Up Studies: Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.Contrast Media: Substances used to allow enhanced visualization of tissues.Gated Blood-Pool Imaging: Radionuclide ventriculography where scintigraphic data is acquired during repeated cardiac cycles at specific times in the cycle, using an electrocardiographic synchronizer or gating device. Analysis of right ventricular function is difficult with this technique; that is best evaluated by first-pass ventriculography (VENTRICULOGRAPHY, FIRST-PASS).Treatment Outcome: Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.Occipital Lobe: Posterior portion of the CEREBRAL HEMISPHERES responsible for processing visual sensory information. It is located posterior to the parieto-occipital sulcus and extends to the preoccipital notch.Coronary Artery Disease: Pathological processes of CORONARY ARTERIES that may derive from a congenital abnormality, atherosclerotic, or non-atherosclerotic cause.Prospective Studies: Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.Sturge-Weber Syndrome: A non-inherited congenital condition with vascular and neurological abnormalities. It is characterized by facial vascular nevi (PORT-WINE STAIN), and capillary angiomatosis of intracranial membranes (MENINGES; CHOROID). Neurological features include EPILEPSY; cognitive deficits; GLAUCOMA; and visual defects.Dobutamine: A catecholamine derivative with specificity for BETA-1 ADRENERGIC RECEPTORS. It is commonly used as a cardiotonic agent after CARDIAC SURGERY and during DOBUTAMINE STRESS ECHOCARDIOGRAPHY.Myocardial Stunning: Prolonged dysfunction of the myocardium after a brief episode of severe ischemia, with gradual return of contractile activity.Stroke Volume: The amount of BLOOD pumped out of the HEART per beat, not to be confused with cardiac output (volume/time). It is calculated as the difference between the end-diastolic volume and the end-systolic volume.Severity of Illness Index: Levels within a diagnostic group which are established by various measurement criteria applied to the seriousness of a patient's disorder.Multidetector Computed Tomography: Types of spiral computed tomography technology in which multiple slices of data are acquired simultaneously improving the resolution over single slice acquisition technology.ROC Curve: A graphic means for assessing the ability of a screening test to discriminate between healthy and diseased persons; may also be used in other studies, e.g., distinguishing stimuli responses as to a faint stimuli or nonstimuli.Brain Diseases: Pathologic conditions affecting the BRAIN, which is composed of the intracranial components of the CENTRAL NERVOUS SYSTEM. This includes (but is not limited to) the CEREBRAL CORTEX; intracranial white matter; BASAL GANGLIA; THALAMUS; HYPOTHALAMUS; BRAIN STEM; and CEREBELLUM.Retrospective Studies: Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.Monte Carlo Method: In statistics, a technique for numerically approximating the solution of a mathematical problem by studying the distribution of some random variable, often generated by a computer. The name alludes to the randomness characteristic of the games of chance played at the gambling casinos in Monte Carlo. (From Random House Unabridged Dictionary, 2d ed, 1993)Radioimmunodetection: Use of radiolabeled antibodies for diagnostic imaging of neoplasms. Antitumor antibodies are labeled with diverse radionuclides including iodine-131, iodine-123, indium-111, or technetium-99m and injected into the patient. Images are obtained by a scintillation camera.Prognosis: A prediction of the probable outcome of a disease based on a individual's condition and the usual course of the disease as seen in similar situations.Chorea: Involuntary, forcible, rapid, jerky movements that may be subtle or become confluent, markedly altering normal patterns of movement. Hypotonia and pendular reflexes are often associated. Conditions which feature recurrent or persistent episodes of chorea as a primary manifestation of disease are referred to as CHOREATIC DISORDERS. Chorea is also a frequent manifestation of BASAL GANGLIA DISEASES.Sodium Pertechnetate Tc 99m: A gamma-emitting radionuclide imaging agent used for the diagnosis of diseases in many tissues, particularly in the gastrointestinal system, cardiovascular and cerebral circulation, brain, thyroid, and joints.Arrhythmias, Cardiac: Any disturbances of the normal rhythmic beating of the heart or MYOCARDIAL CONTRACTION. Cardiac arrhythmias can be classified by the abnormalities in HEART RATE, disorders of electrical impulse generation, or impulse conduction.Myocardial Contraction: Contractile activity of the MYOCARDIUM.Cardiac Surgical Procedures: Surgery performed on the heart.Scattering, Radiation: The diversion of RADIATION (thermal, electromagnetic, or nuclear) from its original path as a result of interactions or collisions with atoms, molecules, or larger particles in the atmosphere or other media. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Hemodynamics: The movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM.Atrophy: Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes.Heart Ventricles: The lower right and left chambers of the heart. The right ventricle pumps venous BLOOD into the LUNGS and the left ventricle pumps oxygenated blood into the systemic arterial circulation.Pentetic Acid: An iron chelating agent with properties like EDETIC ACID. DTPA has also been used as a chelator for other metals, such as plutonium.Electroencephalography: Recording of electric currents developed in the brain by means of electrodes applied to the scalp, to the surface of the brain, or placed within the substance of the brain.Brain Neoplasms: Neoplasms of the intracranial components of the central nervous system, including the cerebral hemispheres, basal ganglia, hypothalamus, thalamus, brain stem, and cerebellum. Brain neoplasms are subdivided into primary (originating from brain tissue) and secondary (i.e., metastatic) forms. Primary neoplasms are subdivided into benign and malignant forms. In general, brain tumors may also be classified by age of onset, histologic type, or presenting location in the brain.Attitude to Computers: The attitude and behavior associated with an individual using the computer.Reference Values: The range or frequency distribution of a measurement in a population (of organisms, organs or things) that has not been selected for the presence of disease or abnormality.Cone-Beam Computed Tomography: Computed tomography modalities which use a cone or pyramid-shaped beam of radiation.Alzheimer Disease: A degenerative disease of the BRAIN characterized by the insidious onset of DEMENTIA. Impairment of MEMORY, judgment, attention span, and problem solving skills are followed by severe APRAXIAS and a global loss of cognitive abilities. The condition primarily occurs after age 60, and is marked pathologically by severe cortical atrophy and the triad of SENILE PLAQUES; NEUROFIBRILLARY TANGLES; and NEUROPIL THREADS. (From Adams et al., Principles of Neurology, 6th ed, pp1049-57)Receptors, Dopamine D2: A subfamily of G-PROTEIN-COUPLED RECEPTORS that bind the neurotransmitter DOPAMINE and modulate its effects. D2-class receptor genes contain INTRONS, and the receptors inhibit ADENYLYL CYCLASES.Corpus Striatum: Striped GRAY MATTER and WHITE MATTER consisting of the NEOSTRIATUM and paleostriatum (GLOBUS PALLIDUS). It is located in front of and lateral to the THALAMUS in each cerebral hemisphere. The gray substance is made up of the CAUDATE NUCLEUS and the lentiform nucleus (the latter consisting of the GLOBUS PALLIDUS and PUTAMEN). The WHITE MATTER is the INTERNAL CAPSULE.Electron Microscope Tomography: A tomographic technique for obtaining 3-dimensional images with transmission electron microscopy.Meningioma: A relatively common neoplasm of the CENTRAL NERVOUS SYSTEM that arises from arachnoidal cells. The majority are well differentiated vascular tumors which grow slowly and have a low potential to be invasive, although malignant subtypes occur. Meningiomas have a predilection to arise from the parasagittal region, cerebral convexity, sphenoidal ridge, olfactory groove, and SPINAL CANAL. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, pp2056-7)Death, Sudden, Cardiac: Unexpected rapid natural death due to cardiovascular collapse within one hour of initial symptoms. It is usually caused by the worsening of existing heart diseases. The sudden onset of symptoms, such as CHEST PAIN and CARDIAC ARRHYTHMIAS, particularly VENTRICULAR TACHYCARDIA, can lead to the loss of consciousness and cardiac arrest followed by biological death. (from Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 7th ed., 2005)Cerebral Arterial Diseases: Pathological conditions of intracranial ARTERIES supplying the CEREBRUM. These diseases often are due to abnormalities or pathological processes in the ANTERIOR CEREBRAL ARTERY; MIDDLE CEREBRAL ARTERY; and POSTERIOR CEREBRAL ARTERY.Feasibility Studies: Studies to determine the advantages or disadvantages, practicability, or capability of accomplishing a projected plan, study, or project.Parkinson Disease: A progressive, degenerative neurologic disease characterized by a TREMOR that is maximal at rest, retropulsion (i.e. a tendency to fall backwards), rigidity, stooped posture, slowness of voluntary movements, and a masklike facial expression. Pathologic features include loss of melanin containing neurons in the substantia nigra and other pigmented nuclei of the brainstem. LEWY BODIES are present in the substantia nigra and locus coeruleus but may also be found in a related condition (LEWY BODY DISEASE, DIFFUSE) characterized by dementia in combination with varying degrees of parkinsonism. (Adams et al., Principles of Neurology, 6th ed, p1059, pp1067-75)Carbon Radioisotopes: Unstable isotopes of carbon that decay or disintegrate emitting radiation. C atoms with atomic weights 10, 11, and 14-16 are radioactive carbon isotopes.Brain Ischemia: Localized reduction of blood flow to brain tissue due to arterial obstruction or systemic hypoperfusion. This frequently occurs in conjunction with brain hypoxia (HYPOXIA, BRAIN). Prolonged ischemia is associated with BRAIN INFARCTION.Neuropsychological Tests: Tests designed to assess neurological function associated with certain behaviors. They are used in diagnosing brain dysfunction or damage and central nervous system disorders or injury.Otoacoustic Emissions, Spontaneous: Self-generated faint acoustic signals from the inner ear (COCHLEA) without external stimulation. These faint signals can be recorded in the EAR CANAL and are indications of active OUTER AUDITORY HAIR CELLS. Spontaneous otoacoustic emissions are found in all classes of land vertebrates.Dementia: An acquired organic mental disorder with loss of intellectual abilities of sufficient severity to interfere with social or occupational functioning. The dysfunction is multifaceted and involves memory, behavior, personality, judgment, attention, spatial relations, language, abstract thought, and other executive functions. The intellectual decline is usually progressive, and initially spares the level of consciousness.Perfusion: Treatment process involving the injection of fluid into an organ or tissue.False Positive Reactions: Positive test results in subjects who do not possess the attribute for which the test is conducted. The labeling of healthy persons as diseased when screening in the detection of disease. (Last, A Dictionary of Epidemiology, 2d ed)AzetidinesCoronary Vessels: The veins and arteries of the HEART.Aphasia: A cognitive disorder marked by an impaired ability to comprehend or express language in its written or spoken form. This condition is caused by diseases which affect the language areas of the dominant hemisphere. Clinical features are used to classify the various subtypes of this condition. General categories include receptive, expressive, and mixed forms of aphasia.Cerebrovascular Disorders: A spectrum of pathological conditions of impaired blood flow in the brain. They can involve vessels (ARTERIES or VEINS) in the CEREBRUM, the CEREBELLUM, and the BRAIN STEM. Major categories include INTRACRANIAL ARTERIOVENOUS MALFORMATIONS; BRAIN ISCHEMIA; CEREBRAL HEMORRHAGE; and others.Neurologic Examination: Assessment of sensory and motor responses and reflexes that is used to determine impairment of the nervous system.Basal Ganglia: Large subcortical nuclear masses derived from the telencephalon and located in the basal regions of the cerebral hemispheres.Cerebral Infarction: The formation of an area of NECROSIS in the CEREBRUM caused by an insufficiency of arterial or venous blood flow. Infarcts of the cerebrum are generally classified by hemisphere (i.e., left vs. right), lobe (e.g., frontal lobe infarction), arterial distribution (e.g., INFARCTION, ANTERIOR CEREBRAL ARTERY), and etiology (e.g., embolic infarction).Parietal Lobe: Upper central part of the cerebral hemisphere. It is located posterior to central sulcus, anterior to the OCCIPITAL LOBE, and superior to the TEMPORAL LOBES.Radiation Dosage: The amount of radiation energy that is deposited in a unit mass of material, such as tissues of plants or animal. In RADIOTHERAPY, radiation dosage is expressed in gray units (Gy). In RADIOLOGIC HEALTH, the dosage is expressed by the product of absorbed dose (Gy) and quality factor (a function of linear energy transfer), and is called radiation dose equivalent in sievert units (Sv).Echocardiography, Stress: A method of recording heart motion and internal structures by combining ultrasonic imaging with exercise testing (EXERCISE TEST) or pharmacologic stress.Coronary Stenosis: Narrowing or constriction of a coronary artery.Isotope Labeling: Techniques for labeling a substance with a stable or radioactive isotope. It is not used for articles involving labeled substances unless the methods of labeling are substantively discussed. Tracers that may be labeled include chemical substances, cells, or microorganisms.Blood Flow Velocity: A value equal to the total volume flow divided by the cross-sectional area of the vascular bed.Computer Peripherals: Various units or machines that operate in combination or in conjunction with a computer but are not physically part of it. Peripheral devices typically display computer data, store data from the computer and return the data to the computer on demand, prepare data for human use, or acquire data from a source and convert it to a form usable by a computer. (Computer Dictionary, 4th ed.)Brain Mapping: Imaging techniques used to colocalize sites of brain functions or physiological activity with brain structures.Rest: Freedom from activity.Myocardial Revascularization: The restoration of blood supply to the myocardium. (From Dorland, 28th ed)Technetium Tc 99m Pentetate: A technetium imaging agent used in renal scintigraphy, computed tomography, lung ventilation imaging, gastrointestinal scintigraphy, and many other procedures which employ radionuclide imaging agents.Fluorine Radioisotopes: Unstable isotopes of fluorine that decay or disintegrate emitting radiation. F atoms with atomic weights 17, 18, and 20-22 are radioactive fluorine isotopes.Tomography, X-Ray: Tomography using x-ray transmission.Vasodilator Agents: Drugs used to cause dilation of the blood vessels.Equipment Design: Methods of creating machines and devices.Computer Literacy: Familiarity and comfort in using computers efficiently.Epilepsy: A disorder characterized by recurrent episodes of paroxysmal brain dysfunction due to a sudden, disorderly, and excessive neuronal discharge. Epilepsy classification systems are generally based upon: (1) clinical features of the seizure episodes (e.g., motor seizure), (2) etiology (e.g., post-traumatic), (3) anatomic site of seizure origin (e.g., frontal lobe seizure), (4) tendency to spread to other structures in the brain, and (5) temporal patterns (e.g., nocturnal epilepsy). (From Adams et al., Principles of Neurology, 6th ed, p313)Cerebellum: The part of brain that lies behind the BRAIN STEM in the posterior base of skull (CRANIAL FOSSA, POSTERIOR). It is also known as the "little brain" with convolutions similar to those of CEREBRAL CORTEX, inner white matter, and deep cerebellar nuclei. Its function is to coordinate voluntary movements, maintain balance, and learn motor skills.Radiation: Emission or propagation of acoustic waves (SOUND), ELECTROMAGNETIC ENERGY waves (such as LIGHT; RADIO WAVES; GAMMA RAYS; or X-RAYS), or a stream of subatomic particles (such as ELECTRONS; NEUTRONS; PROTONS; or ALPHA PARTICLES).Tomography Scanners, X-Ray Computed: X-ray image-detecting devices that make a focused image of body structures lying in a predetermined plane from which more complex images are computed.Epilepsy, Temporal Lobe: A localization-related (focal) form of epilepsy characterized by recurrent seizures that arise from foci within the temporal lobe, most commonly from its mesial aspect. A wide variety of psychic phenomena may be associated, including illusions, hallucinations, dyscognitive states, and affective experiences. The majority of complex partial seizures (see EPILEPSY, COMPLEX PARTIAL) originate from the temporal lobes. Temporal lobe seizures may be classified by etiology as cryptogenic, familial, or symptomatic (i.e., related to an identified disease process or lesion). (From Adams et al., Principles of Neurology, 6th ed, p321)Cysteine: A thiol-containing non-essential amino acid that is oxidized to form CYSTINE.Evaluation Studies as Topic: Studies determining the effectiveness or value of processes, personnel, and equipment, or the material on conducting such studies. For drugs and devices, CLINICAL TRIALS AS TOPIC; DRUG EVALUATION; and DRUG EVALUATION, PRECLINICAL are available.Cerebral Cortex: The thin layer of GRAY MATTER on the surface of the CEREBRAL HEMISPHERES that develops from the TELENCEPHALON and folds into gyri and sulchi. It reaches its highest development in humans and is responsible for intellectual faculties and higher mental functions.Light: That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.Pilot Projects: Small-scale tests of methods and procedures to be used on a larger scale if the pilot study demonstrates that these methods and procedures can work.Hyperemia: The presence of an increased amount of blood in a body part or an organ leading to congestion or engorgement of blood vessels. Hyperemia can be due to increase of blood flow into the area (active or arterial), or due to obstruction of outflow of blood from the area (passive or venous).Heart Diseases: Pathological conditions involving the HEART including its structural and functional abnormalities.Luminescent Measurements: Techniques used for determining the values of photometric parameters of light resulting from LUMINESCENCE.Serotonin Plasma Membrane Transport Proteins: Sodium chloride-dependent neurotransmitter symporters located primarily on the PLASMA MEMBRANE of serotonergic neurons. They are different than SEROTONIN RECEPTORS, which signal cellular responses to SEROTONIN. They remove SEROTONIN from the EXTRACELLULAR SPACE by high affinity reuptake into PRESYNAPTIC TERMINALS. Regulates signal amplitude and duration at serotonergic synapses and is the site of action of the SEROTONIN UPTAKE INHIBITORS.Fatty Acids: Organic, monobasic acids derived from hydrocarbons by the equivalent of oxidation of a methyl group to an alcohol, aldehyde, and then acid. Fatty acids are saturated and unsaturated (FATTY ACIDS, UNSATURATED). (Grant & Hackh's Chemical Dictionary, 5th ed)Vehicle Emissions: Gases, fumes, vapors, and odors escaping from the cylinders of a gasoline or diesel internal-combustion engine. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed & Random House Unabridged Dictionary, 2d ed)Computer Systems: Systems composed of a computer or computers, peripheral equipment, such as disks, printers, and terminals, and telecommunications capabilities.Functional Laterality: Behavioral manifestations of cerebral dominance in which there is preferential use and superior functioning of either the left or the right side, as in the preferred use of the right hand or right foot.Middle Cerebral Artery: The largest of the cerebral arteries. It trifurcates into temporal, frontal, and parietal branches supplying blood to most of the parenchyma of these lobes in the CEREBRAL CORTEX. These are the areas involved in motor, sensory, and speech activities.Analysis of Variance: A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.Cardiac Pacing, Artificial: Regulation of the rate of contraction of the heart muscles by an artificial pacemaker.Cerebral Angiography: Radiography of the vascular system of the brain after injection of a contrast medium.Cardiac Tamponade: Compression of the heart by accumulated fluid (PERICARDIAL EFFUSION) or blood (HEMOPERICARDIUM) in the PERICARDIUM surrounding the heart. The affected cardiac functions and CARDIAC OUTPUT can range from minimal to total hemodynamic collapse.Cardiomegaly: Enlargement of the HEART, usually indicated by a cardiothoracic ratio above 0.50. Heart enlargement may involve the right, the left, or both HEART VENTRICLES or HEART ATRIA. Cardiomegaly is a nonspecific symptom seen in patients with chronic systolic heart failure (HEART FAILURE) or several forms of CARDIOMYOPATHIES.Benzamides: BENZOIC ACID amides.Cardiac Catheterization: Procedures in which placement of CARDIAC CATHETERS is performed for therapeutic or diagnostic procedures.Holmium: Holmium. An element of the rare earth family of metals. It has the atomic symbol Ho, atomic number 67, and atomic weight 164.93.Spectrometry, Fluorescence: Measurement of the intensity and quality of fluorescence.Carotid Stenosis: Narrowing or stricture of any part of the CAROTID ARTERIES, most often due to atherosclerotic plaque formation. Ulcerations may form in atherosclerotic plaques and induce THROMBUS formation. Platelet or cholesterol emboli may arise from stenotic carotid lesions and induce a TRANSIENT ISCHEMIC ATTACK; CEREBROVASCULAR ACCIDENT; or temporary blindness (AMAUROSIS FUGAX). (From Adams et al., Principles of Neurology, 6th ed, pp 822-3)Models, Biological: Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.Carotid Artery, Internal: Branch of the common carotid artery which supplies the anterior part of the brain, the eye and its appendages, the forehead and nose.Case-Control Studies: Studies which start with the identification of persons with a disease of interest and a control (comparison, referent) group without the disease. The relationship of an attribute to the disease is examined by comparing diseased and non-diseased persons with regard to the frequency or levels of the attribute in each group.Postprandial Period: The time frame after a meal or FOOD INTAKE.Postoperative Complications: Pathologic processes that affect patients after a surgical procedure. They may or may not be related to the disease for which the surgery was done, and they may or may not be direct results of the surgery.Retinal Rod Photoreceptor Cells: Photosensitive afferent neurons located in the peripheral retina, with their density increases radially away from the FOVEA CENTRALIS. Being much more sensitive to light than the RETINAL CONE CELLS, the rod cells are responsible for twilight vision (at scotopic intensities) as well as peripheral vision, but provide no color discrimination.Dopamine: One of the catecholamine NEUROTRANSMITTERS in the brain. It is derived from TYROSINE and is the precursor to NOREPINEPHRINE and EPINEPHRINE. Dopamine is a major transmitter in the extrapyramidal system of the brain, and important in regulating movement. A family of receptors (RECEPTORS, DOPAMINE) mediate its action.Adenosine: A nucleoside that is composed of ADENINE and D-RIBOSE. Adenosine or adenosine derivatives play many important biological roles in addition to being components of DNA and RNA. Adenosine itself is a neurotransmitter.

Biological factors and overestimation of left ventricular ejection fraction by gated SPECT. (1/59)

BACKGROUND: Some patients present an overestimated left ventricular ejection fraction (LVEF) on electrocardiogram-gated myocardial scintigraphy (gated SPECT). OBJECTIVE: To establish the relationship between biological factors and overestimated LVEF. METHODS: We selected 3838 patients who underwent gated SPECT between May 20, 2000 and September 16, 2005 with normal perfusion images and LVEF > or =50%. The following variables were analyzed: gender (29.4% females and 70.6% males), age (from 20 to 94 years - mean: 56 years), weight (from 33.5 to 150 kg - mean: 79.6 kg), height (from 138 to 220 cm - mean: 171 cm) and BMI (from 13.9 to 54 - mean: 27.2). In a subgroup of 1002 patients who underwent echocardiogram, the diastolic diameter (from 36 to 68 mm - mean 47.5 mm) and systolic diameter (from 22 to 41 mm - mean 29.8 mm) variables were included. The patients were divided into two groups: normal LVEF (< or =80%) and overestimated LVEF (>80%). The odds ratio (OR) for presenting an overestimated LVEF was calculated for each variable using logistic regression. RESULTS: The following odds ratios were found (p < 0.005): female gender OR = 3.585 (95%CI: 2.745 to 4.683), age in years OR = 1.020 (95%CI: 1.011 to 1.029) and height in cm OR = 0.893 (95%CI: 0.829 to 0.962). Weight and BMI were not significantly associated with LVEF (p>0.2). In the subgroup of 1002 patients, a statistically significant influence was found in overestimated LVEF values for the systolic diameter, gender and height variables. CONCLUSION: Although systolic diameter influences the overestimation of LVEF, the gender and height variables have an independent influence on LVEF overestimation by gated SPECT.  (+info)

Echocardiographic and cardiac single photon emission computed tomography predictors of left ventricle reverse remodeling after surgical revascularization in patients with ischemic cardiomyopathy and left ventricle systolic dysfunction. (2/59)

BACKGROUND: The extent of scar or viable hypocontractile myocardial tissue determines postinfarction left ventricle remodeling. The aim of this pilot study was to evaluate the revascularization effect in a group of patients with ischemic cardiomyopathy and LV systolic dysfunction indicated for surgical revascularization, based on evidence for multivessel disease on coronarography and viable myocardium (CMR, SPECT). AIMS: To evaluate the revascularization effect in patients with ischemic LV systolic dysfunction and to find preoperative predictors of revascularization effect. METHODS: 33 patients (64+/-11 years) with baseline LVEF 34.9+/-9.3 % were included in the study. After a follow-up of 10.7+/-1.2 months, ECHO and SPECT were performed again. The whole group of patients was divided according to revascularization effect (postoperative increase LVEF > 5 % and postoperative decrease LVESV > 5 % compared with baseline) into revascularization responders (R, n = 22) and nonresponders (NR, n = 11). RESULTS: At baseline there was no difference between the subgroups in LVEF (R = 35.7+/-11.0 % vs. NR = 34.3+/-8.2 %), EDV (R = 183.6+/-43.2 vs. NR = 180.2+/-80.5 ml), ESV (R = 118.5+/-40.4 vs. NR = 119.7+/-55.2 ml). The responders showed in a revascularization effect subanalysis differences in the values of LVEF (+9.8+/-8.1 %, p < 0.009), reduction of EDV (-39.9+/-50.9 ml, p = 0.05) and ESV (-35.4+/-42.6 ml, p = 0,002) compared with baseline. The only preoperative parameters predicting LV reverse remodeling were the T(E-Em) (R = -10.6+/-44.1 vs. NR = 29.7+/-43.7 ms, p = 0.037) and the size of fixed perfusion defect (FPD) (R = 11.9+/-13.5 vs. NR = 22.9+/-15.3 % of LV, p = 0.044). CONCLUSIONS: Patients with ischemic LV systolic dysfunction with a preoperatively determined myocardial viability develop LV reverse remodeling. The only preoperative parameters predicting LV reverse remodeling were echocardiographic T(E-Em) and FPD on SPECT.  (+info)

Low-dose dobutamine gated-SPECT analysis of left ventricular segmental wall thickening in ischemic cardiomyopathy. (3/59)

INTRODUCTION AND OBJECTIVES: The objective of this study was to use low-dose dobutamine (LDD) gated single-photon emission computed tomography (SPECT) to evaluate segmental thickening of the left ventricle (LV) and its relationship with changes in ejection fraction (EF) and ventricular volumes in patients with ischemic cardiomyopathy. METHODS: This prospective multicenter study involved 89 patients with ischemic cardiomyopathy (i.e., EF < or =40%) who underwent LDD gated-SPECT at rest. The LV was divided into 17 segments and systolic thickening was assessed in a total of 1513 segments during LDD infusion. RESULTS; A significant increase in LVEF (33.2% vs. 30.8%; P< .001) was observed during LDD infusion and occurred at the expense of a reduction in end-systolic volume (130.5 mL vs. 136.4 mL; P=.005). The increase in EF was > or =5% in 33.7% of patients, while the EF decreased by > or =5% in 5.6% of patients. With LDD infusion, both an improvement in > or =3 segments with severely decreased baseline thickening (odds ratio [OR] = 18.3; 95% confidence interval [CI], 5.3-63) and an improvement in > or =10 segments with mild-to-moderate alterations in baseline thickening (OR = 4.53; 95% CI, 1.26-16.16) were associated with a > or =5% increase in LVEF. CONCLUSIONS: During the assessment of global left ventricular contractile reserve by LDD gated-SPECT, attention should be paid not only to the behavior of segments with severely decreased baseline thickening, which are generally regarded as indicating viability, but also to segments with mild-to-moderate alterations and to those in which thickening decreases.  (+info)

Incremental prognostic value of cardiac function assessed by ECG-gated myocardial perfusion SPECT for the prediction of future acute coronary syndrome. (4/59)

BACKGROUND: The prognostic value of ECG-gated rest 201Tl/stress 99mTc-tetrofosmin myocardial perfusion single-photon emission computed tomography for the prediction of acute coronary syndrome (ACS: myocardial infarction (MI) and unstable angina (UA)) and the implications of ejection fraction (EF) has not yet been defined in Japanese. METHODS AND RESULTS: The 1,895 patients were followed up for the occurrence ACS. The mean follow-up interval was 26.9+/-15.5 months. The 142 patients with revascularization within 60 days were censored. Summed stress score (SSS) and summed difference score (SDS) were calculated. The 19 MI and 29 UA occurred (1.1% and 1.6%, respectively). Univariate Cox analysis showed that hypertension (Wald 5.09, p<0.05), poststress EF (Wald 10.9, p<0.01), SSS (Wald 12.4, p<0.001) and SDS (Wald 18.7, p<0.001) were significant predictors of ACS. Multivariate Cox analysis showed that hypertension (Wald 4.27, p<0.05) and SDS (Wald 8.59, p<0.01) were independent predictors. When multiple clinical risk factors (number of coronary risk factors > or =2), significant ischemia (SDS > or =4) and low EF (EF <45%) were applied to multivariate Cox analysis, the combination of significant ischemia and low EF showed the highest predictive value (Wald 11.9; p<0.001) for future ACS. CONCLUSION: Poststress EF added incremental prognostic value for the prediction of ACS.  (+info)

Respiratory motion detection and correction in ECG-gated SPECT: a new approach. (5/59)

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Intensive cardiovascular risk factors therapy and prevalence of silent myocardial ischaemia in patients with type 2 diabetes. (6/59)

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Validation of gated blood-pool SPECT regional left ventricular function measurements. (7/59)

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Single photon emission computed tomography: an alternative imaging modality in left ventricular evaluation. (8/59)

Various diagnostic imaging modalities have been used for quantitative left ventricular (LV) parameters. Because of the suboptimal value of the most widely used technology, two-dimensional (2D) echocardiography, 3D ultrasonographic imaging has improved accuracy for LV volume and function. Single photon emission computed tomography (SPECT) is another diagnostic method where LV volumetric and functional parameters can be accurately provided by gated myocardial perfusion tomographic slices. First pass radionuclide venticulography is another imaging modality which has some practical limitations. Despite lower ejection fraction (EF) values compared with invasive approach, noninvasive techniques are accurate in determination of normal and depressed EF. Noninvasive techniques with 3D approach including gated SPECT are beneficial for not only global but also regional LV evaluation. It has been mentioned that the slight difference between echocardiography and SPECT could be caused by the diverse population studied. The results of diagnostic stress tests support that SPECT is feasible to use in evaluation of LV volume and functional analysis. Magnetic resonance imaging is an expensive modality to use routinely, but it preserves its importance in selected patients for providing precise LV geometric data.  (+info)

*List of MeSH codes (E01)

... positron-emission tomography MeSH E01.370.350.350.800.800 --- tomography, emission-computed, single-photon MeSH E01.370.350.350 ... computer-assisted MeSH E01.370.350.350.800 --- tomography, emission-computed MeSH E01.370.350.350.800.700 --- ... gated blood-pool imaging MeSH E01.370.370.050.650.650.950 --- ventriculography, first-pass MeSH E01.370.370.065 --- angioscopy ... cardiac MeSH E01.370.370.380.250 --- exercise test MeSH E01.370.370.380.400 --- heart auscultation MeSH E01.370.370.380.400.500 ...

*Iterative reconstruction

"EM reconstruction algorithm for emission and transmission tomography". Journal of Computer Assisted Tomography. 8 (2): 306-316 ... Geman, Stuart; McClure, Donald E. (1985). "Bayesian image analysis: An application to single photon emission tomography". ... Applying a Level Set Method for Resolving Physiologic Motions in Free-Breathing and Non-gated Cardiac MRI. FIMH, 2013, (PDF) ... Tomographic reconstruction Positron Emission Tomography Tomogram Computed Tomography Magnetic Resonance Imaging Inverse problem ...
Background: Phase analysis from gated single photon emission computed tomography myocardial perfusion imaging (GSPECT MPI) has emerged as an attractive means to assess left ventricular mechanical dyssynchrony. Whether dyssynchrony assessed by GSPECT MPI can identify patients at increased risk of mortality is unknown.. Methods: We identified all patients with angiographically significant coronary disease and a GSPECT MPI in the Duke Databank for Cardiovascular Disease between July 2003 and August 2009. The range of time during which 95% of the left ventricle is initiating contraction (phase bandwidth) and the degree of heterogeneity in the distribution of segmental initiation of mechanical contraction (phase standard deviation (SD)) by GSPECT MPI were measured. To evaluate the relationship between each measure of dyssynchrony and long-term survival, unadjusted and adjusted Cox proportional hazards models were constructed.. Results: A total of 1434 patients were identified.The median age was 64 ...
Introduction: Diastolic dyssynchrony is increasingly being recognized in both the adult and pediatric population. Increasing diastolic dyssynchrony has correlated with increased pulmonary capillary wedge pressures and worse clinical outcomes in patients with normal cardiac anatomy. No data exist in patients with single right ventricle (sRV) physiology. Goal of this study was to determine if diastolic dyssynchrony in patients with sRV physiology correlates with ventricular end-diastolic pressures (VEDP) obtained via cardiac catheterization.. Methods: Tissue Doppler imaging (TDI) and strain rate (SR) analysis of sRV patients undergoing catheterization were performed. TDI analysis was performed at the level of the atrioventricular valve. Time interval from onset of QRS to peak TDI e wave of the respective walls was obtained. Differences in intervals were calculated: QRS(RV) - QRS(IVS) and QRS(RV) - QRS(LV). The sRV was separated into a six segment model for SR analysis. Time interval from onset of ...
If you specify the WLLCHISQ option in the TABLES statement, PROC SURVEYFREQ computes a Wald test for independence based on the log odds ratios. For more information about Wald tests, see the section Wald Chi-Square Test. For a two-way table of R rows and C columns, the Wald log-linear test is based on the (R - 1)(C - 1)-dimensional array of elements ...
I was diagnosed with a small heart mummur 11 years ago when I was pregnant with my son. Doctors told me it was small and it was nonthing to worry about. My mother and her side of her family have Cong...
46 patients with a large anterior myocardial infarction (peak CK 2399-11213U/L, peak Tn I 68-249 ng/dL) were included in the study 6-9 days after primary PCI. The control group involved 12 patients not subjected to cell therapy (1:4 assignment). To evaluate myocardial perfusion and viability, regional and global left ventricular contractility, GSPECT was performed 2 days prior to autologous CD34+ cells transcoronary application. In addition, in a subgroup of 23 consecutive patients the cells were labeled with 99mTc-HMPAO to assess their early myocardial retention (i.e., homing to the infarct zone vs. border zone vs. non-infarcted area, myocardial SPECT) and proportion of retention in the heart vs. other organs (whole body SPECT). After 6 months, GSPECT was repeated ...
Hypertension is one of the most important risk factors for cardiovascular disease. However, hypertension may also result in left ventricular dyssynchrony (LVD) which is characterized by delayed activation of certain ventricular segments leading to un
Cute lil hearts. Also shown - Big Hearts, Medium Hearts. Vannas Choice yarn and Freshstitches Design. Purchase of a heart supports Jump Rope For Heart and Hoops For Heart.
Okay, I admit it. I posted this entire release just so I could wonder aloud about the use of "office" as a verb. Is that common practice and I just missed it? Ill admit I was caught behind the times with "effort" as a verb. I heard some guy on sports talk radio this morning utter the sentence "were efforting Stephen A. Smith right now," meaning that theyre trying to get the loud mouth basketball commenter who just got canned (or maybe "not retained") by ESPN on the phone. When the sports guys have bought into the new use of the word, Im just a curmudgeon for disliking it, I suppose. I dont want to be all Andy Rooney here, but does the English language not have enough words? Weve got way more than anyone else, so I dont see why weve got to make up new ways to use words weve already got. Plus, its not like its more Twitterifically efficient or anything: "He offices out of"=17 characters; "He is based at"=14 characters. Maybe he didnt want to be "based" (because it sounded too base). ...
Small heart syndrome is associated with a small heart shadow on a chest X-ray or magnetic resonance imaging. It was first proposed in 1944 as "neurocirculatory asthenia." Current studies show that small heart syndrome is associated with a smaller left ventricular chamber size and diminished cardiac stroke volume.[1] Small heart syndrome is characterized with weakness or fatigue even after ordinary exertion, heart palpitation, dyspnea, and fainting. Miwa and Fujita have shown that it is significantly more prevalent in ME/CFS patient (61%) compared to a control group (24%).[2] ...
Read "Robust and automatic diagnosis of the intraventricular mechanical dyssynchrony for the left ventricle in cardiac magnetic resonance images, International Journal of Computer Assisted Radiology and Surgery" on DeepDyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips.
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Patients with chest pain who underwent SPECT myocardial perfusion imaging (MPI) with an ultralow-radiation-dose gamma camera had no major cardiac events a year later. The research, published in the April issue of the Journal of Nuclear Medicine, indicates that MPI radiation dose can be slashed without adverse clinical impact.
DENVER -- The use of regadenoson (Lexiscan) is safe and can lead to cost and time efficiencies in patients undergoing exercise SPECT myocardial perfusion imaging.
Hello, I am trying to understand some results I got (see below) and any assistance will be greatly appreciated. I have run a number of conditional logit models (with cluster-adjusted robust SEs) and usually, if you get a greater Wald chi-square value, you also get a greater pseudo r-square. But the models below are strange in that the first one has a great pseudo r-square value while the second one has a greater Wald chi-square value. The only thing that changes from one model to the next are the third and fourth variables starting from the bottom (i.e., in the second model, a_lneuclkm and m_lneuclkm have been substituted by a_lneuclmins and m_lneuclmins). Does anyone have any information about how the Wald test statistic is calculated so that I can relate this to how the log-likelihood and the pseudo r-square are calculated (and work out why they might be behaving in this way)? Thanks very much, Lucia. Model 1 . clogit choice commerc100 nostations popdens unemp10 imdincome imdhealth ...
Very scary indeed! Ive had 2 similar situation where Ive either gone to the ER or to my doctor (when it wasnt that bad, but I knew I needed it checked) and the bad time was inflammation around my heart and the 2nd time was, what my doctor thinks, an allergic reaction to my ex-husbands cats (we were married at the time) - inflammation but not quite the same or bad as the first time it happened. But, yeah, EKGs, check Xrays, the whole bit and then super duper ibuprofen!! I havent had any other recurrences in a number of years, but it is very very scary (the first time, I even had my left arm going number in addition to the chest pain and shortness of breath!!). Hope he feels better very soon!!. ReplyDelete ...
2006 erschien von Wald Geist Winter die erste Demo Siegreich ist das Eis, welche damals gut gefiel. Ende Dezember ist nun mit Teufelskreise das Debütalbum erschienen. Wald Geist Winter hat sich natürlich weiterentwickelt und anno 2010/2011 klingt man nicht mehr ganz so rau wie noch auf der ersten Demo. Grimmig ist der Black Metal des Duos aber nach wie vor. Einen Einklang hat man sich gespart und so legt man mit Heimkehr auch gleich direkt … mehr. ...
This work involves the detection and monitoring of solvent interactions with heavy oil and bitumen. Two nondestructive methodslow-field nuclear magnetic resonance (NMR) and X-ray computer-assisted tomography (CAT)were used. It is shown that low-field NMR can be a very useful tool in understanding the relationship of viscosity, density, and asphaltene precipitation in bitumen−solvent mixtures. Such mixtures are present in solvent-related heavy oil and bitumen recovery processes, such as vapor extraction (VAPEX). As a solvent comes into contact with a heavy oil or bitumen sample, the mobility of hydrogen-bearing molecules of both solvent and oil changes. These changes are detectable through changes in the NMR relaxation characteristics of both the solvent and the oil and can be correlated to mass flux and concentration changes. Based on Ficks second law, diffusion coefficients were calculated for combinations of three oils and six solvents. X-ray CAT scanning was also used in parallel for ...
Buy the Vets Choice Health Extension Holistic Small Heart Shaped Treats 1 Lb for your pet plus read product reviews, see photos and watch videos at PetStore.com.
OBJECTIVES The value of gated single-photon emission computed tomography technetium-99m methoxyisobutylisonitrile (gated SPECT (99m)Tc-MIBI) in children is not yet established probably because gated SPECT (99m)Tc-MIBI has rarely been used in pediatric clinical and research studies. The purpose of this study was to evaluate perfusion abnormalities and left ventricular (LV) function by gated SPECT (99m)Tc-MIBI in children and adolescents with severe congenital heart disease (CHD). METHODS Seventeen children and adolescents with severe CHD (11 boys and six girls, mean age 11+/-4 years) underwent 2-day rest-stress (11 boys) or 1-day rest (six girls) gated SPECT (99m)Tc-MIBI. Myocardial perfusion was evaluated by a 17-segment model with a 5-point score to derive the summed stress score, the summed rest score (SRS), and the summed difference score based on the 4D-MSPECT software results. The extent of myocardial perfusion abnormalities was also expressed as a percentage of the LV size. The 4D-MSPECT
The NM Emory Cardiac Toolbox (ECTb) v4.1 provides advanced tools for cardiac SPECT and PET analysis including comparison of perfusion to viability data, display of 3D images with coronary overlays and gated 3D cine, normal limits for agent match/mismatch as well as optional phase analysis for wall motion and evaluation of thickening. ...
Structural Characterization: Use of Transmission Electron Microscopy (TEM) in high resolution, energy filtered, conventional and convergent beam modes to characterize nitride nanostructures (quantum wells and dots). Quantitative analysis of HRTEM images using the geometric phase analysis, a projection method and images simulations ...
Aging Backwards is a term coined by Dr. Michael Wald, The Blood Detective, to describe how each of us has the biological potential to actually reverse-age. Dr. Wald gives specific nutritional strategies that have been demonstrated in scientific studies to affect our fundamental aging process. Dr. Wald can be reached by calling 914-552-1442. www.IntegratedNutritionNY.com/email: [email protected] view more ...
0067] In general, processor 502 may generate a variety of images or signals for display to a user via display 508 based on the measured torso-surface potentials, calculated torso-surface or estimated cardiac activation times, or the degree of change in electrical dyssynchrony. For example, a graded response reflecting the efficacy of a particular location of the LV lead 102 during biventricular pacing or single ventricle fusion pacing may be provided to the physician in terms of a red, yellow and green signal. A red signal may be shown if the reduction in electrical dyssynchrony during CRT pacing compared to intrinsic rhythm is negative (an increase in electrical dyssynchrony) or minimal, e.g., less than 5%. A yellow signal may be triggered if there is some reduction in electrical dyssynchrony during CRT pacing compared to intrinsic rhythm, for example between 5% and 15%, but there may be potentially better sites for lead placement. If the reduction in electrical dyssynchrony during CRT pacing ...
SPECT scans were reviewed in a blinded fashion by 3 independent expert readers using the 17-segment model for standardized myocardial segmentation. At rest and stress, each segment was scored on a 0 (normal) to 4 (absent contrast/radiotracer uptake) scale by each of the 3 blinded readers according to the amount of contrast or radiotracer the myocardium in the segment absorbed. If the stress score was ≥ 2 and the rest score was less than the stress score, the segment was counted as having a reversible defect.. The number of segments with reversible defects was categorized as absence (0 - 1 reversible segments) or presence (≥ 2 defects reversible segments) of ischemia.. Each reader was defined as having self-agreement based upon identical categorization of a given participant as absent or present for ischemia for both the initial and second stress visits.. Majority agreement is if at least 2 out of the 3 blinded readers demonstrated self-agreement for a given participant. ...
This is Digital Version of (Ebook) 978-0898383805 Silent Myocardial Ischemia: Proceedings of the Symposium on New Drugs and De Product Will Be Deliver
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Sweet Heart blocks. Comes in a rainbow of different colors. Hang on the wall or decorate a mantel or shelf. Great accents for the home, nursery or ...
Results Pacing was associated with reduced GLS after 2 years, although 2-year GLS was lower in RVA (−13.9±4.1 vs −15.5±4.6, p=0.02). RVA was an independent correlate of ΔGLS, although there was a minor difference in ΔGLS between the RVA and non-RVA groups (−1.8±3.6 vs −0.8±3.4%, p=0.07), reflecting impairment of GLS at baseline in RVA. Apical strain was significantly lower in RVA than those in non-RVA at baseline and 2 years (both p,0.01). Dyssynchrony and discoordination parameters at 2 years also showed significant deterioration in RVA. Apical strain, dyssynchrony and discoordination parameters at 2 years were significantly associated with ΔGLS. ...
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HXPN IS GAINING GREAT MOMENTUM! WE ARE ABOUT TO SEE FIRWORKS! WATCH IT ON MONDAY MAY 21! __________ Company: Harris Exploration Inc Symbol: HXPN Price: 0.78 5-day Target: $2.5 Rating: Agressive Buy __________ HXPN HAS GAINED OVER 50% IN 2 DAYS! WE ARE EXPECTING GAINS TOPPING 200% AND MORE! GET IN NOW WHILE YOU STILL CAN MAKE PROFIT! ________________________________________ Yes, so I imagined. I was afraid there could be little chance of my h Small heart had Harriet for visiting. Only half an hour before her fri Emma, said Mr. Knightley presently, I have a piece of news for you. Me!--not at all, replied Mr. Knightley, rather displeased; I do not It is a most repulsive quality, indeed, said he. Oftentimes very co Yes--it seems to depend upon nothing but the ill-humour of Mrs. Churc This was too true for contradiction. Unwelcome as it was, Mr. Woodhous Mr. Weston, with triumph of a different sort, was confessing that he h And Mrs. Perry and the children, how are they? do the children ...
Background: It is of great clinical importance to exclude myocardial infarction in patients with suspected coronary artery disease who do not have stress-induced ischemia. The diagnostic use of myocardial perfusion single-photon emission computed tomography (SPECT) in this situation is sometimes complicated by attenuation artifacts that mimic myocardial infarction. Imaging in the prone position has been suggested as a method to overcome this problem. Methods: In this study, 52 patients without known prior infarction and no stress-induced ischemia on SPECT imaging were examined in both supine and prone position. The results were compared with cardiac magnetic resonance imaging (CMR) with delayed-enhancement technique to confirm or exclude myocardial infarction. Results: There were 63 defects in supine-position images, 37 of which disappeared in the prone position. None of the 37 defects were associated with myocardial infarction by CMR, indicating that all of them represented attenuation ...
Newer multimodality imaging may help uncover unique ventricular morphology that might be consistent with unrecognized forms of possible cardiomyopathies (1-3). We describe one such possibility in a 52-year-old man with chronic atypical chest pain and no prior cardiac history who had a fixed anterior defect on a stress myocardial perfusion single-photon emission computed tomography. Coronary angiography revealed normal epicardial arteries without evidence of atherosclerotic lesions, luminal stenosis, thrombus, or dissection but a left ventricular angiogram (Fig. 1,Online Video 1) showed an unusual appearance, with a large left ventricular aneurysm and multiple small-to-moderate size diverticula with surrounding areas of prominent trabeculation of the basal anterior, apical and basal, and mid-inferior walls. Cardiac magnetic resonance (Online Videos 2 and 3) confirmed the presence of a large mid-distal anterior and anteroseptal wall aneurysm with a relatively narrow neck surrounded by thinned ...
Semantic Scholar extracted view of Correct interpretation of a myocardial perfusion SPECT study in a patient with Ebsteins anomaly through recognition of septal artifact. by Gabriel B. Grossman et al.
The study was approved by the Mayo Clinic Institutional Review Board. Patients provided written informed consent. We prospectively recruited a sample of 121 patients hospitalized with their first AMI between November 2002 and October 2007. These patients represented a subset of patients who were enrolled in a prospective, community-based AMI study from Olmsted County, Minnesota, designed to examine changes in the incidence of AMI diagnosis resulting from using cTnT in place of the myocardial bound fraction of creatine kinase (CK-MB). Details of this study have been published elsewhere (14). For myocardial infarction diagnosis, we applied a computerized algorithm that integrated ischemic symptoms, the Minnesota code of the electrocardiograms, and cTnT levels (14). For this algorithm, 3 electrocardiograms were electronically available and were coded using a previously validated electronic coding system. For those patients who were transferred from another medical facility in Olmsted County to the ...
Left ventricular strain and dyssynchrony in three directions (longitudinal, radial and circumferential) in the sham-operated group (sham), the pacing-induced he
Pharmacologic stress with dipyridamole has provided useful diagnostic, as well as prognostic, information in patients undergoing thallium-201 myocardial perfusion imaging. With its ultrashort half-life and a potent and consistent vasodilator effect, adenosine may be the coronary vasodilator of choice with myocardial perfusion imaging.. Fifty-one healthy subjects and 93 patients with suspected coronary artery disease constituted the study group. In this multicenter study the comparative safety and diagnostic efficacy of single-photon emission computed tomography (SPECT) thallium imaging during adenosine-induced coronary hyperemia was compared with exercise treadmill stress. There was a mean increase in heart rate of 37% and a mean decrease in diastolic blood pressure of 5% during the adenosine infusion of 140 μg/kg per min for 6 min. Adenosine infusion was well tolerated in 95% of the subjects. Side effects requiring intervention occurred in seven subjects (5%). None of the subjects experienced ...
Abstract. Background: An analysis of the US National Cardiovascular Data Registry has revealed that only 38% of patients referred for coronary angiography after non-invasive coronary testing have relevant coronary obstruction (CO) (≥70%) of one or more coronary arteries.. Methods: A single-center trial was undertaken in 165 consecutive, symptomatic patients with either known or suspected coronary disease and/or valve disease(VHD) who agreed to undergo cardiac catheterization and coronary angiography if stress myocardial perfusion imaging was abnormal. A total of 116 patients with abnormal SPECT MPI tests, persistent chest pain, or significant VHD underwent final analysis. An MCG coronary obstruction (CO) score of ≥ 4.0 was considered indicative of relevant CO (≥70%) in one or more coronary arteries. Angiographic results were finalized by consensus of two angiographers.. Results: CO (≥70%) was present in 53 of 116 patients (46%). The MCG CO score was significantly higher for patients with ...
Diagnostic medical test Single-photon emission computed tomography scan including diseases and symptoms diagnosed or ruled out by this test.
I will never forget the day that we received a large envelope from Make-A-Wish Iowa. I quickly read through everything. I was excited to share the great news with Jax that he was getting a wish. I could not wait to see what he would wish for. Make-A-Wish tells you to have fun and enjoy the process…have your child dream big….for ANYTHING. So that is what we did, we said to Jax, "if you could wish for anything in the world what would you want?".. I watched him silently start thinking about it. Almost instantly he looks at us with a sparkle in his eye and says, "Oh, I know. I have the perfect wish." I couldnt wait to hear. Then it comes.. "Im going to wish for a small heart.". Of course, all he really wants is a cure too. As I fought back tears I told him that would be my wish too but thats not how it works. Make-A-Wish cannot heal your heart.. Jax was 10 lbs 2 oz at birth. That is a BIG baby. What we would soon find out was that he had a big heart too. He spent 12 days in neonatal intensive ...

LV dyssynchrony as assessed by phase analysis of gated SPECT myocardial perfusion imaging in patients with Wolff-Parkinson...LV dyssynchrony as assessed by phase analysis of gated SPECT myocardial perfusion imaging in patients with Wolff-Parkinson...

... using phase analysis of gated single photon emission co ... Cardiac-Gated Single-Photon Emission Computer-Assisted ... using phase analysis of gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI).. METHODS: ... Phase analysis of gated SPECT MPI was used to assess LV dyssynchrony pre- and post-RFA.. RESULTS: Among the 45 patients, 3 had ... Electrophysiologic Techniques, Cardiac / methods. Female. Humans. Male. Middle Aged. Myocardial Perfusion Imaging / methods. ...
more infohttp://www.biomedsearch.com/nih/LV-dyssynchrony-as-assessed-by/22532253.html

A systematic analysis of factors which may impact upon tomographic perfusion imaging measurements: Implications for the use of...A systematic analysis of factors which may impact upon tomographic perfusion imaging measurements: Implications for the use of...

Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography * Swine * Thorax * Myocardial Reperfusion ... Each animal underwent four modes of gamma camera imaging: a cardiac and respiratory gated SPECT study, an ungated SPECT study, ... Each animal underwent four modes of gamma camera imaging: a cardiac and respiratory gated SPECT study, an ungated SPECT study, ... Each animal underwent four modes of gamma camera imaging: a cardiac and respiratory gated SPECT study, an ungated SPECT study, ...
more infohttps://mayoclinic.pure.elsevier.com/en/publications/a-systematic-analysis-of-factors-which-may-impact-upon-tomographi

Daniel C Lee - Fingerprint
     - Northwestern ScholarsDaniel C Lee - Fingerprint - Northwestern Scholars

Positron-Emission Tomography Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography Electrocardiography ...
more infohttps://www.scholars.northwestern.edu/en/persons/daniel-c-lee/fingerprints/

Cardiac Arrhythmias | Cardiology Conferences | Global Events 2018 | USACardiac Arrhythmias | Cardiology Conferences | Global Events 2018 | USA

Cardiac Surgeons and Experts from USA, Australia, Europe, Asia, Middle East at Cardiology Conference, Interventional Cardiology ... events, Heart Disease Meetings, Cardiac Nursing Congress during 2017, 2018 ... Track 7-11Cardiac-gated single photon emission computer assisted tomography. *Track 7-12Gated blood-pool imaging ... Track 3:Cardiac Surgery Cardiac (heart) surgery is surgery on the heart or great vessels performed by cardiac surgeons. ...
more infohttps://cardiac.conferenceseries.com/2018/call-for-abstracts.php

Echocardiography & Cardiac ImagingEchocardiography & Cardiac Imaging

Cardiac Surgeons and Experts from USA, Australia, Europe, Asia, Middle East at Cardiology Conference, Interventional Cardiology ... events, Heart Disease Meetings, Cardiac Nursing Congress during 2017, 2018 ... Cardiac-gated imaging techniques. *Gated blood-pool imaging. *Cardiac-gated single photon emission computer assisted tomography ... Cardiac Regeneration - Clinical Cardiology Congress 2018 (Hong Kong). *Cardiac Regeneration & Remodeling - Cardiac Nursing 2018 ...
more infohttps://cardiac.conferenceseries.com/events-list/echocardiography-cardiac-imaging

Gated Blood-Pool Imaging | Profiles RNSGated Blood-Pool Imaging | Profiles RNS

Cardiac-Gated Imaging Techniques. *Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography ... Reconstruction of dynamic gated cardiac SPECT. Med Phys. 2006 Nov; 33(11):4384-94. ... "Gated Blood-Pool Imaging" is a descriptor in the National Library of Medicines controlled vocabulary thesaurus, MeSH (Medical ... This graph shows the total number of publications written about "Gated Blood-Pool Imaging" by people in this website by year, ...
more infohttps://profiles.umassmed.edu/display/116616

Effects of motion, attenuation, and scatter corrections on gated cardi by Xiaofeng Niu, Yongyi Yang et al."Effects of motion, attenuation, and scatter corrections on gated cardi" by Xiaofeng Niu, Yongyi Yang et al.

In the experiments the authors use Monte Carlo simulated cardiac gated SPECT imaging based on the 4D NURBS-based cardiac-torso ... In low-count gated studies, it can have even greater impact than other degrading factors. Both attenuation and scatter ... In gated cardiac single photon emission computed tomography (SPECT), image reconstruction is often hampered by various ... Artifacts; Cardiac-Gated Single-Photon Emission Computer-Assisted; Tomography; Female; Humans; Image Enhancement; Image ...
more infohttps://escholarship.umassmed.edu/radiology_pubs/15/

Search Articles | University of Toronto LibrariesSearch Articles | University of Toronto Libraries

Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography , Myocardial Perfusion Imaging , Care and treatment , ... single photon emission computed tomography (11) 11 Filter by. Remove filter. single-photon emission computed tomography (11) 11 ... Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography - methods , Myocardial Ischemia - complications , Sensitivity ... EMISSION COMPUTED-TOMOGRAPHY , Tomography, Emission-Computed, Single-Photon - methods , Prognosis , Diabetes Complications - ...
more infohttps://query.library.utoronto.ca/index.php/search/q?kw=Author:Heo,%20Jaekyeong

Search Articles | University of Toronto LibrariesSearch Articles | University of Toronto Libraries

Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography , Myocardial Perfusion Imaging , Stroke Volume , Sympathetic ... Cardiac patients , Mortality , Medicine, Experimental , Heart , Occlusion , Cardiac muscle , peroneal nerve , Muscles , ... single unit , SINGLE-UNIT ANALYSIS , NOREPINEPHRINE TURNOVER , VASOCONSTRICTOR NEURONS , microneurography , SYMPATHETIC-NERVE ... Cardiac Output, Low - etiology , Heart Rate - drug effects , Cardiac Catheterization , Hypertrophy, Right Ventricular - ...
more infohttps://query.library.utoronto.ca/index.php/search/q?kw=SubjectTerms:Sympathetic%20Fibers,%20Postganglionic%20-%20physiopathology

A quantitative study of motion estimation methods on 4D cardiac gated  by Wenyuan Qi, Yongyi Yang et al."A quantitative study of motion estimation methods on 4D cardiac gated " by Wenyuan Qi, Yongyi Yang et al.

The periodic OFE method is used to exploit the inherent periodic nature in cardiac gated images. In this method, the optical ... known cardiac motion derived from the NURBS-based cardiac-torso (NCAT) phantom. ... we investigate the effect of different optical flow estimation methods for motion-compensated temporal processing in gated ... Motion-compensated temporal processing can have a major impact on improving the image quality in gated cardiac single photon ...
more infohttps://escholarship.umassmed.edu/radiology_pubs/17/

Acute Myocardial Infarct Imaging: Overview, Radiography, Computed TomographyAcute Myocardial Infarct Imaging: Overview, Radiography, Computed Tomography

... is a condition characterized by ischemic injury and necrosis of the cardiac muscle. Ischemic injury occurs when the blood ... Abbott BG, Abdel-Aziz I, Nagula S. Selective use of single-photon emission computed tomography myocardial perfusion imaging in ... The Rule Out Myocardial Infarction Using Computer Assisted Tomography (ROMICAT) Study. Circ Cardiovasc Qual Outcomes. 2013 Sep ... Prognostic value of stress-gated Tc-99m sestamibi SPECT after acutemyocardial infarction. Am J Cardiol. 2001 Feb 15. 87(4):381- ...
more infohttps://emedicine.medscape.com/article/350175-overview

List of MeSH codes (E01) - WikipediaList of MeSH codes (E01) - Wikipedia

... positron-emission tomography MeSH E01.370.350.350.800.800 --- tomography, emission-computed, single-photon MeSH E01.370.350.350 ... computer-assisted MeSH E01.370.350.350.800 --- tomography, emission-computed MeSH E01.370.350.350.800.700 --- ... gated blood-pool imaging MeSH E01.370.370.050.650.650.950 --- ventriculography, first-pass MeSH E01.370.370.065 --- angioscopy ... cardiac MeSH E01.370.370.380.250 --- exercise test MeSH E01.370.370.380.400 --- heart auscultation MeSH E01.370.370.380.400.500 ...
more infohttps://en.wikipedia.org/wiki/List_of_MeSH_codes_(E01)

Pazhenkottil, Aju P<...Pazhenkottil, Aju P<...

... dose computed tomography for attenuation correction of cadmium-zinc-telluride single photon emission computed tomography ... Impact on Image Quality in Ultralow-Dose Coronary Computed Tomography Angiography. Journal of Computer Assisted Tomography, 40( ... Fused cardiac hybrid imaging with coronary computed tomography angiography and positron emission tomography in patients with ... Gated SPECT myocardial perfusion imaging with cadmium-zinc-telluride detectors allows real-time assessment of dobutamine-stress ...
more infohttps://www.zora.uzh.ch/view/authors_for_linking_in_citation/Pazhenkottil=3AAju_P=3A=3A.html

Computer-assisted determination of left ventricular endocardial borders reduces variability in the echocardiographic assessment...Computer-assisted determination of left ventricular endocardial borders reduces variability in the echocardiographic assessment...

... assessment and automatically determined LVEF from quantitative myocardial gated single photon emission computed tomography ( ... cardiac magnetic resonance and as of late also cardiac computed tomography. Two-dimensional echocardiography has, due to its ... gated single-photon emission computed tomography versus two-dimensional echocardiography. Eur J Nucl Med. 2001, 28: 1610-1615. ... assessment and automatically determined LVEF from quantitative myocardial gated single photon emission computed tomography ( ...
more infohttps://cardiovascularultrasound.biomedcentral.com/articles/10.1186/1476-7120-6-55

Detection of coronary artery disease with perfusion stress echocardiography using a novel ultrasound imaging agent: two Phase 3...Detection of coronary artery disease with perfusion stress echocardiography using a novel ultrasound imaging agent: two Phase 3...

Tc single photon emission computed tomography (SPECT) for coronary artery disease (CAD) detection. PSE is a novel technique for ... Gated Blood-Pool Imaging (MeSH) * Humans (MeSH) * Image Enhancement (MeSH) * Image Interpretation, Computer-Assisted (MeSH) ... Cardiac & Cardiovascular Systems * Cardiovascular System & Cardiology * DIAGNOSIS * DIPYRIDAMOLE STRESS * DOBUTAMINE * EMISSION ... METHODS AND RESULTS: Chronic, stable, chest pain patients (n=662) underwent Imagify PSE and gated SPECT imaging at rest and ...
more infohttps://scholars.latrobe.edu.au/display/publication236547

Ian S. Rogers, M.D., M.P.H. | Stanford Medicine ProfilesIan S. Rogers, M.D., M.P.H. | Stanford Medicine Profiles

Images for CTA, computed tomography perfusion (CTP), and single-photon emission computed tomography (SPECT) were each read by 2 ... Rule Out Myocardial Infarction using Computer Assisted Tomography) Trial JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY Hoffmann ... ECG-gated, 8-slice cardiac multidetector CT was performed. We measured the mPA and transverse axial diameter of the ascending ... who underwent both single-photon emission computed tomography (SPECT)-MPI stress testing and 64-slice computed tomography ...
more infohttps://med.stanford.edu/profiles/ian-rogers?tab=bio

Diagnostic value of left ventricular dyssynchrony after exercise and at rest in the detection of multivessel coronary artery...Diagnostic value of left ventricular dyssynchrony after exercise and at rest in the detection of multivessel coronary artery...

Tc-sestamibi gated single-photon emission computed tomography and coronary angiography. LV mechanical dyssynchrony was ... Tomography, Emission-Computed, Single-Photon. *Computer Assisted Diagnosis. *Transient Ischemic Dilation. *synovial sarcoma ... Clinical usefulness of a novel program Heart Function View for evaluating cardiac function from gated myocardial perfusion ... exercise and at rest in the detection of multivessel coronary artery disease on single-photon emission computed tomography.. @ ...
more infohttps://www.semanticscholar.org/paper/Diagnostic-value-of-left-ventricular-dyssynchrony-Hida-Chikamori/645aa75b27ad8c7e63cd5284d2ed9dc88c11d5f3

Iterative reconstruction - WikipediaIterative reconstruction - Wikipedia

"EM reconstruction algorithm for emission and transmission tomography". Journal of Computer Assisted Tomography. 8 (2): 306-316 ... Geman, Stuart; McClure, Donald E. (1985). "Bayesian image analysis: An application to single photon emission tomography". ... Applying a Level Set Method for Resolving Physiologic Motions in Free-Breathing and Non-gated Cardiac MRI. FIMH, 2013, (PDF) ... Tomographic reconstruction Positron Emission Tomography Tomogram Computed Tomography Magnetic Resonance Imaging Inverse problem ...
more infohttps://en.wikipedia.org/wiki/Iterative_reconstruction

Fuchs, Tobias A<...Fuchs, Tobias A<...

... value as an adjunct to coronary artery calcium score and myocardial perfusion single-photon emission computed tomography. ... Impact on Image Quality in Ultralow-Dose Coronary Computed Tomography Angiography. Journal of Computer Assisted Tomography, 40( ... and age-related differences in rest and post-stress left ventricular cardiac function determined by gated SPECT. International ... Fused cardiac hybrid imaging with coronary computed tomography angiography and positron emission tomography in patients with ...
more infohttps://www.zora.uzh.ch/view/authors_for_linking_in_citation/Fuchs=3ATobias_A=3A=3A.html

PET and MRI in cardiac imaging: from validation studies to integrated applications | SpringerLinkPET and MRI in cardiac imaging: from validation studies to integrated applications | SpringerLink

Introduction Positron emission tomography (PET) is the gold standard for non-invasive assessment of myocardial viability and ... MR-IMPACT: comparison of perfusion-cardiac magnetic resonance with single-photon emission computed tomography for the detection ... Medical image computing and computer-assisted intervention - MICCAI 2001. Lecture Notes in Computer Science, vol. 2208. 4th ... Dual cardiac-respiratory gated PET: implementation and results from a feasibility study. Eur J Nucl Med Mol Imaging 2007;34: ...
more infohttps://link.springer.com/article/10.1007%2Fs00259-008-0980-1

Coronary Computed Tomographic Angiography | CirculationCoronary Computed Tomographic Angiography | Circulation

Consequently, 4 randomized, controlled trials in the ED have compared CTA with usual care6-8 and single-photon emission CT,9 ... In the Rule Out Myocardial Infarction Using Computer Assisted Tomography (ROMICAT) I trial, in which providers were blinded to ... ACCF/SCCT/ACR/AHA/ASE/ASNC/NASCI/SCAI/SCMR 2010 appropriate use criteria for cardiac computed tomography: a report of the ... For instance, with prospective gated ECG triggering, the average effective dose is ≈3 to 4 mSv, equivalent to the annual level ...
more infohttp://circ.ahajournals.org/content/130/23/2052

Journal of Computer Assisted Tomography Page 18Journal of Computer Assisted Tomography Page 18

Source: Journal of Computer Assisted Tomography - November 1, 2014 Category: Radiology Tags: Cardiac Imaging Source Type: ... Evaluation of Selective Positron Emission Tomography Template Method for Spatial Normalization of Amyloid Imaging With 11C- ... ResultsIncreasing photon energy was associated with reduced metal artifacts in GSI images (P. Source: Journal of Computer ... After 6 weeks, precontrast, single-energy computed tomography (SECT) and postcontrast DECT were performed, and HFF maps were ...
more infohttps://medworm.com/journal/journal-of-computer-assisted-tomography/18/

Patente US20080242978 - Method and apparatus for registering a physical space to image space - Google PatentesPatente US20080242978 - Method and apparatus for registering a physical space to image space - Google Patentes

... such as positron emission tomography (PET) combined with CT, or single photon emission computer tomography (SPECT) combined ... The present disclosure relates to a method and apparatus for performing a computer assisted surgical procedure, and ... Gated Image Acquisition and Patient Model Construction. US20120099772 *. 20 Oct 2010. 26 Abr 2012. Medtronic Navigation, Inc.. ... The image data registered with the 4D information can show the brain (or anatomy of interest) moving during the cardiac or ...
more infohttp://www.google.es/patents/US20080242978

Reproducibility of Chronic and Acute Infarct Size Measurement by Delayed Enhancement-Magnetic Resonance Imaging | JACC: Journal...Reproducibility of Chronic and Acute Infarct Size Measurement by Delayed Enhancement-Magnetic Resonance Imaging | JACC: Journal...

Single-photon emission computed tomography IS imaging has been used extensively as surrogate end point in clinical trials (2). ... equipped with a five-element cardiac phased-array coil for signal reception. A vectorcardiogram for gating and triggering was ... whereas in other trials semi-automatic computer-assisted algorithms were used (8,13,14,16). Recently, the most objective ... 2003) Contrast-enhanced MRI and routine single photon emission computed tomography (SPECT) perfusion imaging for detection of ...
more infohttp://www.onlinejacc.org/content/47/8/1641?ijkey=ea66621c65937a2dba8dfa5c32bc432af70b0e25&keytype2=tf_ipsecsha

Prognosis and Outcome: State of the Evidence | Springer for Research & DevelopmentPrognosis and Outcome: State of the Evidence | Springer for Research & Development

Prognostic value of multislice computed tomography and gated single-photon emission computed tomography in patients with ... rule out myocardial infarction using computer assisted tomography) trial. J Am Coll Cardiol. 2009;53:1642-50.CrossRefGoogle ... ACCF/SCCT/ACR/AHA/ASE/ASNC/NASCI/SCAI/SCMR 2010 appropriate use criteria for cardiac computed tomography. A report of the ... matched comparison with myocardial perfusion single-photon emission computed tomography. J Cardiovasc Comput Tomogr. 2008;2:93- ...
more infohttps://rd.springer.com/chapter/10.1007%2F978-1-60327-237-7_51
  • Abstract: The technological advances in computed tomography (CT) scanners and their continuously increased use have raised concern about the patient-induced risks from the CT procedures. (medworm.com)
  • In 49 patients with a previous infarction or recent angiography with ≥70% stenosis, or both, the addition of gated images changed the percentage of "abnormal" scan interpretations from 78% (38 of 49) to 92% (45 of 49). (onlinejacc.org)
  • These scenarios may occur in intraoperative CT, in cardiac CT, or when metal artifacts require the exclusion of some portions of the projection data. (wikipedia.org)
  • MI may also manifest itself as sudden cardiac death, which may not be apparent on autopsy (because necrosis takes time to develop). (medscape.com)
  • Overall, use of degrading corrections in 4D reconstruction is shown to be most effective for improving both reconstruction accuracy of the myocardium and detectability of perfusion defects in gated images. (umassmed.edu)
  • Because history alone is often inadequate to identify patients who may be safely discharged, 3 it is common practice to use observation and serial cardiac biomarkers for patient evaluation. (ahajournals.org)
  • Additionally, exercise testing and vasodilator stress testing are commonly used, although such testing can be performed only after an observation period, which includes serial cardiac biomarkers. (ahajournals.org)
  • The initial evaluation of acute chest pain requires an ECG and cardiac biomarkers ( Figure 1A ). (ahajournals.org)
  • In addition, LGE provides incremental prognostic value to MACE and cardiac mortality beyond common clinical, angiographic, and functional predictors. (ahajournals.org)
  • Cardiac PET has the advantage of higher spatial resolution, temporal resolution, and, in many cases, a decreased radiation exposure to patients. (medscape.com)
  • METHODS: We consider the following three methods for obtaining the image motion in 4D reconstruction: (1) the Horn-Schunck optical flow equation (OFE) method, (2) a recently developed periodic OFE method, and (3) known cardiac motion derived from the NURBS-based cardiac-torso (NCAT) phantom. (umassmed.edu)
  • Defect severity was significantly underestimated with the addition of a chest cavity and tomographic reconstruction but was unaltered by cardiac and respiratory motion. (elsevier.com)
  • Here, iterative reconstruction techniques are usually a better, but computationally more expensive alternative to the common filtered back projection (FBP) method, which directly calculates the image in a single reconstruction step. (wikipedia.org)
  • In low-count gated studies, it can have even greater impact than other degrading factors. (umassmed.edu)
  • A dual energy window data acquisition algorithm then determines non-scatter photons in a primary energy window utilizing the scatter fraction. (google.com)
  • Beyond this depth, high spatial resolution cannot be maintained since photons are multiply scattered. (uwm.edu)