A short-lived radioactive tracer isotope which decays by emitting a positron, chemically incorporated into a metabolically active molecule, is injected into the living subject (usually into blood circulation). There is a waiting period while the metabolically active molecule (usually a sugar) becomes concentrated in tissues of interest, then the subject is placed in the imaging scanner. The short-lived isotope decays, emitting a positron. After travelling up to a few millimeters the positron annihilates with an electron, producing a pair of ...

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Positron emission tomography, Positron emission tomography - Description, Positron emission tomography - Applications, Positron emission tomography - PET scans safety

Read more here: » Positron emission tomography: Encyclopedia II - Positron emission tomography - Description

See also:

Positron emission tomography, Positron emission tomography - Description, Positron emission tomography - Applications, Positron emission tomography - PET scans safety

Read more here: » Positron emission tomography: Encyclopedia II - Positron emission tomography - PET scans safety

The most famous use of the positron in fiction was Isaac Asimov's use in his robots' positronic brains. It is likely that he chose to use positrons because they were relatively newly-discovered when he was first writing about the robots. Perhaps in an homage to Asimov, in the Star Trek universe the android Data, his "brother" Lore, "daughter" Lal, and other sundry related androids also have positronic brains. In Hideaki Anno's Neon Genesis Evangelion, the positron rifle, based upon the ATHENA tests in Europe, is used ...

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Positron, Positron - The positron in fiction

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The diagnostic tests in cardiology are methods of identifying heart conditions associated with healthy vs. unhealthy, pathologic, heart function. Cardiology diagnostic tests and procedures - Bedside. Cardiology diagnostic tests and procedures - History. Obtaining a medical history is always the first "test", part of understanding the likelihood of significant disease, as detectable within the current limitations of clinical medicine. Yet heart problems often produce no symptoms ...

Including:

Cardiology diagnostic tests and procedures - Bedside
Cardiology diagnostic tests and procedures - History Cardiology diagnostic tests and procedures - Auscultation
Cardiology diagnostic tests and procedures - Laboratory
Cardiology diagnostic tests and procedures - Blood tests
Cardiology diagnostic tests and procedures - Electrophysiology
Cardiology diagnostic tests and procedures - Electrocardiogram Cardiology diagnostic tests and procedures - Holter monitor Cardiology diagnostic tests and procedures - Event monitor Cardiology diagnostic tests and procedures - Cardiac stress testing
Cardiology diagnostic tests and procedures - Medical imaging
Cardiology diagnostic tests and procedures - Coronary catheterization Cardiology diagnostic tests and procedures - Echocardiogram Cardiology diagnostic tests and procedures - Intravascular ultrasound Cardiology diagnostic tests and procedures - Positron emission tomography Cardiology diagnostic tests and procedures - Computed axial tomography Cardiology diagnostic tests and procedures - Magnetic resonance imaging
Cardiology diagnostic tests and procedures - Related topics

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Computed tomography (CT), originally known as computed axial tomography (CAT) and body section roentgenography, is a medical imaging method employing tomography where digital geometry processing is used to generate a three-dimensional image of the internals of an object from a large series of two-dimensional X-ray images taken around a single axis of rotation. The word "tomography" is derived from the Greek tomos (slice) and graphia (describing). CT produces a series of axial images which can be manipulated, through a process known as windo ...

Including:

Computed tomography - History Computed tomography - Principles Computed tomography - Diagnostic use
Computed tomography - Cranial CT Computed tomography - Chest CT Computed tomography - Cardiac CT Computed tomography - Abdominal and pelvic CT Computed tomography - Extremities

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PET may mean: Commodore PET (Personal Electronic Transactor) Pierre Elliott Trudeau (1919–2000), an influential Canadian politician Politiets Efterretningstjeneste, the Danish Security Intelligence Service Polyethylene terephthalate, a common plastic material Positron emission tomography, a three-dimensional imaging technique in nuclear medicine Potential evapotranspiration, a measure of the atmospheric demand for water vapour from evaporation and transpiration

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Cardiology diagnostic tests and procedures - Blood tests. A variety of blood tests are available for analyzing cholesterol transport behavior, HDL, LDL, triglycerides, lipoprotein little a, homocysteine, C-reactive protein, blood sugar control: fasting, after eating or averages using glycosylated albumen or hemoglobin, myoglobin, creatine kinase, troponin, brain-type natriuretic peptide, etc. to assess the evolution of coronary artery disease and evidence of existing damage. A great many more physiologic markers related to atherosclerosis a ...

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Cardiology diagnostic tests and procedures, Cardiology diagnostic tests and procedures - Bedside, Cardiology diagnostic tests and procedures - History, Cardiology diagnostic tests and procedures - Auscultation, Cardiology diagnostic tests and procedures - Laboratory, Cardiology diagnostic tests and procedures - Blood tests, Cardiology diagnostic tests and procedures - Electrophysiology, Cardiology diagnostic tests and procedures - Electrocardiogram, Cardiology diagnostic tests and procedures - Holter monitor, Cardiology diagnostic tests and procedures - Event monitor, Cardiology diagnostic tests and procedures - Cardiac stress testing, Cardiology diagnostic tests and procedures - Medical imaging, Cardiology diagnostic tests and procedures - Coronary catheterization, Cardiology diagnostic tests and procedures - Echocardiogram, Cardiology diagnostic tests and procedures - Intravascular ultrasound, Cardiology diagnostic tests and procedures - Positron emission tomography, Cardiology diagnostic tests and procedures - Computed axial tomography, Cardiology diagnostic tests and procedures - Magnetic resonance imaging, Cardiology diagnostic tests and procedures - Related topics

Read more here: » Cardiology diagnostic tests and procedures: Encyclopedia II - Cardiology diagnostic tests and procedures - Laboratory

Cardiology diagnostic tests and procedures - Electrocardiogram. Electrocardiography (ECG/EKG) monitors electrical activity of the heart, primarily as recorded from the skin surface. A 12 lead recording, 6 for the front plane and 6 for the lower chest crossectional plane, is the most commonly used form. Cardiology diagnostic tests and procedures - Holter monitor. A Holter monitor records a continuous EKG rhythm pattern (rarely a full EKG) for 24 hours or more. Thes ...

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Cardiology diagnostic tests and procedures, Cardiology diagnostic tests and procedures - Bedside, Cardiology diagnostic tests and procedures - History, Cardiology diagnostic tests and procedures - Auscultation, Cardiology diagnostic tests and procedures - Laboratory, Cardiology diagnostic tests and procedures - Blood tests, Cardiology diagnostic tests and procedures - Electrophysiology, Cardiology diagnostic tests and procedures - Electrocardiogram, Cardiology diagnostic tests and procedures - Holter monitor, Cardiology diagnostic tests and procedures - Event monitor, Cardiology diagnostic tests and procedures - Cardiac stress testing, Cardiology diagnostic tests and procedures - Medical imaging, Cardiology diagnostic tests and procedures - Coronary catheterization, Cardiology diagnostic tests and procedures - Echocardiogram, Cardiology diagnostic tests and procedures - Intravascular ultrasound, Cardiology diagnostic tests and procedures - Positron emission tomography, Cardiology diagnostic tests and procedures - Computed axial tomography, Cardiology diagnostic tests and procedures - Magnetic resonance imaging, Cardiology diagnostic tests and procedures - Related topics

Read more here: » Cardiology diagnostic tests and procedures: Encyclopedia II - Cardiology diagnostic tests and procedures - Electrophysiology

Cardiology diagnostic tests and procedures - Coronary catheterization. Coronary catheterization uses pressure monitoring and blood sampling through a catheter inserted into the heart through blood vessels in the leg to determine the functioning of the heart, and, following injections of radiocontrast dye, uses X-ray fluoroscopy, typically at 30 frame/s, to visualize the position and size of blood of within the heart chambers and arteries. Coronary angiography is used to determine the patency and configuration of the coronary artery lumens. ...

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Cardiology diagnostic tests and procedures, Cardiology diagnostic tests and procedures - Bedside, Cardiology diagnostic tests and procedures - History, Cardiology diagnostic tests and procedures - Auscultation, Cardiology diagnostic tests and procedures - Laboratory, Cardiology diagnostic tests and procedures - Blood tests, Cardiology diagnostic tests and procedures - Electrophysiology, Cardiology diagnostic tests and procedures - Electrocardiogram, Cardiology diagnostic tests and procedures - Holter monitor, Cardiology diagnostic tests and procedures - Event monitor, Cardiology diagnostic tests and procedures - Cardiac stress testing, Cardiology diagnostic tests and procedures - Medical imaging, Cardiology diagnostic tests and procedures - Coronary catheterization, Cardiology diagnostic tests and procedures - Echocardiogram, Cardiology diagnostic tests and procedures - Intravascular ultrasound, Cardiology diagnostic tests and procedures - Positron emission tomography, Cardiology diagnostic tests and procedures - Computed axial tomography, Cardiology diagnostic tests and procedures - Magnetic resonance imaging, Cardiology diagnostic tests and procedures - Related topics

Read more here: » Cardiology diagnostic tests and procedures: Encyclopedia II - Cardiology diagnostic tests and procedures - Medical imaging

X-ray slice data is generated using an X-ray source that rotates around the object; X-ray sensors are positioned on the opposite side of the circle from the X-ray source. Many data scans are progressively taken as the object is gradually passed through the gantry. They are combined together by the mathematical procedure known as tomographic reconstruction. Newer machines with faster computer systems and newer software strategies can process not only individual cross sections but continuously changing cross sections as the gantry, with ...

See also:

Computed tomography, Computed tomography - History, Computed tomography - Principles, Computed tomography - Diagnostic use, Computed tomography - Cranial CT, Computed tomography - Chest CT, Computed tomography - Cardiac CT, Computed tomography - Abdominal and pelvic CT, Computed tomography - Extremities, Computed tomography - Three dimensional 3D reconstruction, Computed tomography - The principle, Computed tomography - An example, Computed tomography - Segmentation, Computed tomography - CT imaging as graphic art

Read more here: » Computed tomography: Encyclopedia II - Computed tomography - Principles

Since its introduction in the 1970s, CT has become an important tool in medical imaging to supplement X-rays and medical ultrasonography. Although it is still quite expensive, it is the gold standard in the diagnosis of a large number of different disease entities. Computed tomography - Cranial CT. Diagnosis of cerebrovascular accidents and intracranial hemorrhage is the most frequent reason for a "head CT" or "CT brain". Scanning is done with or without intravenous contrast agents. CT genera ...

See also:

Computed tomography, Computed tomography - History, Computed tomography - Principles, Computed tomography - Diagnostic use, Computed tomography - Cranial CT, Computed tomography - Chest CT, Computed tomography - Cardiac CT, Computed tomography - Abdominal and pelvic CT, Computed tomography - Extremities, Computed tomography - Three dimensional 3D reconstruction, Computed tomography - The principle, Computed tomography - An example, Computed tomography - Segmentation, Computed tomography - CT imaging as graphic art

Read more here: » Computed tomography: Encyclopedia II - Computed tomography - Diagnostic use

Other proposed or developed medical imaging techniques (often termed modalities) include: diffuse optical tomography elastography electrical impedance tomography nuclear medicine optoacoustic imaging ophthalmology A-scan B-scan corneal topography Heidelberg retinal tomography Optical coherence tomography scanning laser ophthalmoscopy positron emission tomography Some of these techniques are still at a research stage and not yet used in clinical routines.

Medical imaging, Medical imaging - Origins, Medical imaging - Modern imaging technology, Medical imaging - Radiographs, Medical imaging - Fluoroscopy, Medical imaging - Computed tomography, Medical imaging - Magnetic resonance imaging, Medical imaging - Ultrasound, Medical imaging - Creation of three-dimensional images, Medical imaging - Other imaging techniques, Medical imaging - Non-diagnostic imaging

Read more here: » Medical imaging: Encyclopedia II - Medical imaging - Other imaging techniques

Computed tomography - The principle. Mathematically the result of a CT scan is a 3 dimensional matrix of numbers representing the radiodensity of the different parts of the body examined. Let us call this matrix the volume. Now consider a certain level of radiodensity and cast an imaginary ray through the volume. There are two possibilities: (a) our ray goes through the volume without hitting a point of the given or greater radiodensity, (b) there is a point at which the ray first hits a value equal or greater th ...

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Computed tomography, Computed tomography - History, Computed tomography - Principles, Computed tomography - Diagnostic use, Computed tomography - Cranial CT, Computed tomography - Chest CT, Computed tomography - Cardiac CT, Computed tomography - Abdominal and pelvic CT, Computed tomography - Extremities, Computed tomography - Three dimensional 3D reconstruction, Computed tomography - The principle, Computed tomography - An example, Computed tomography - Segmentation, Computed tomography - CT imaging as graphic art

Read more here: » Computed tomography: Encyclopedia II - Computed tomography - Three dimensional 3D reconstruction

The CT system was invented in 1972 by Godfrey Newbold Hounsfield of EMI Central Research Laboratories (now Sensaura [1] owned by Creative Technology Ltd.) using X-rays. Allan McLeod Cormack of Tufts University independently invented the same process and they shared a Nobel Prize in medicine in 1979. The first scanner, known as the EMI Scanner, took several hours to acquire the raw data and several days to produce the images. The first EMI scanner was limited to making tomographic sections of the brain. It required the use of a water-containi ...

See also:

Computed tomography, Computed tomography - History, Computed tomography - Principles, Computed tomography - Diagnostic use, Computed tomography - Cranial CT, Computed tomography - Chest CT, Computed tomography - Cardiac CT, Computed tomography - Abdominal and pelvic CT, Computed tomography - Extremities, Computed tomography - Three dimensional 3D reconstruction, Computed tomography - The principle, Computed tomography - An example, Computed tomography - Segmentation, Computed tomography - CT imaging as graphic art

Read more here: » Computed tomography: Encyclopedia II - Computed tomography - History

The CT system was invented in 1972 by Godfrey Newbold Hounsfield of EMI Central Research Laboratories (now Sensaura [1] owned by Creative Technology Ltd.) using X-rays. Allan McLeod Cormack of Tufts University independently invented the same process and they shared a Nobel Prize in medicine in 1979. The first scanner, known as the EMI Scanner, took several hours to acquire the raw data and several days to produce the images. The first EMI scanner was limited to making tomographic sections of the brain. It required the use of a water-containi ...

See also:

Computed tomography, Computed tomography - History, Computed tomography - Principles, Computed tomography - Diagnostic use, Computed tomography - Cranial CT, Computed tomography - Chest CT, Computed tomography - Cardiac CT, Computed tomography - Abdominal and pelvic CT, Computed tomography - Extremities

Read more here: » Computed tomography: Encyclopedia II - Computed tomography - History

X-ray slice data is generated using an X-ray source that rotates around the object; X-ray sensors are positioned on the opposite side of the circle from the X-ray source. Many data scans are progressively taken as the object is gradually passed through the gantry. They are combined together by the mathematical procedure known as tomographic reconstruction. Newer machines with faster computer systems and newer software strategies can process not only individual cross sections but continuously changing cross sections as the gantry, with ...

See also:

Computed tomography, Computed tomography - History, Computed tomography - Principles, Computed tomography - Diagnostic use, Computed tomography - Cranial CT, Computed tomography - Chest CT, Computed tomography - Cardiac CT, Computed tomography - Abdominal and pelvic CT, Computed tomography - Extremities

Read more here: » Computed tomography: Encyclopedia II - Computed tomography - Principles

Since its introduction in the 1970s, CT has become an important tool in medical imaging to supplement X-rays and medical ultrasonography. Although it is still quite expensive, it is the gold standard in the diagnosis of a large number of different disease entities. Computed tomography - Cranial CT. Diagnosis of cerebrovascular accidents and intracranial hemorrhage is the most frequent reason for a "head CT" or "CT brain". Scanning is done without intravenous contrast agents (contrast may rese ...

See also:

Computed tomography, Computed tomography - History, Computed tomography - Principles, Computed tomography - Diagnostic use, Computed tomography - Cranial CT, Computed tomography - Chest CT, Computed tomography - Cardiac CT, Computed tomography - Abdominal and pelvic CT, Computed tomography - Extremities

Read more here: » Computed tomography: Encyclopedia II - Computed tomography - Diagnostic use

As a medical specialty, radiology can be classified into two subfields. Diagnostic radiology is concerned with the use of various imaging modalities to aid in the diagnosis of disease. Radiation therapy uses radiation to treat diseases such as cancer. While originally encompassed within radiology, therapeutic radiology — or, as it is now called, radiation oncology — is now a separate field. Radiologyy is a widely divers religion and s ...

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Radiology, Radiology - Subdivisions, Radiology - Training, Radiology - Diagnostic radiology, Radiology - Plain radiography, Radiology - CT scanning, Radiology - Ultrasound, Radiology - MRI/NMR, Radiology - Nuclear medicine

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Diagnostic radiologists must complete four years of medical school (M.D. or D.O.) plus a five year of post-graduate training (residency). The first year of residency is a preliminary year in medicine, surgery or both, after which a four-year diagnostic radiology residency follows. During residency, both oral and written national examinations must be passed for board certification in diagnostic radiology. There are two separate written examinations required for certification by the American Board of Radiology, one covering the physics of medi ...

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Radiology, Radiology - Subdivisions, Radiology - Training, Radiology - Diagnostic radiology, Radiology - Plain radiography, Radiology - CT scanning, Radiology - Ultrasound, Radiology - MRI/NMR, Radiology - Nuclear medicine

Read more here: » Radiology: Encyclopedia II - Radiology - Training

Since 1970 Zeki has been based at University College, being appointed the Professor of Neurobiology in 1980. He was Co-Head of the Wellcome Department of Cognitive Neuroscience at University College London from 1994 to 2001. Zeki has conducted anatomical and physiological studies of the primate visual brain. Since 1987, he has used positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) to study the human visual brain. Zeki has lectured on the subject the world over. Among the more than 50 named lect ...

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Semir Zeki, Semir Zeki - Formative influences, Semir Zeki - Time at University College London, Semir Zeki - Scientific achievements, Semir Zeki - Life outside of science, Semir Zeki - Acknowledgement

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