PET-CTPositron emission tomography–computed tomography (better known as PET-CT or PET/CT) is a nuclear medicine technique which combines, in a single gantry, a positron emission tomography (PET) scanner and an x-ray computed tomography (CT) scanner, to acquire sequential images from both devices in the same session, which are combined into a single superposed () image. Thus, functional imaging obtained by PET, which depicts the spatial distribution of metabolic or biochemical activity in the body can be more precisely aligned or correlated with anatomic imaging obtained by CT scanning.
Positron emission tomographyPositron emission tomography (PET) is a functional imaging technique that uses radioactive substances known as radiotracers to visualize and measure changes in metabolic processes, and in other physiological activities including blood flow, regional chemical composition, and absorption. Different tracers are used for various imaging purposes, depending on the target process within the body. For example, -FDG is commonly used to detect cancer, NaF is widely used for detecting bone formation, and oxygen-15 is sometimes used to measure blood flow.
ZZ, or z, is the 26th and last letter of the Latin alphabet, as used in the modern English alphabet, the alphabets of other western European languages and others worldwide. Its usual names in English are zed ('zɛd) and zee ('ziː), with an occasional archaic variant izzard ('ɪzərd). In most English-speaking countries, including Australia, Canada, India, Ireland, New Zealand, South Africa and the United Kingdom, the letter's name is zed zɛd, reflecting its derivation from the Greek letter zeta (this dates to Latin, which borrowed Y and Z from Greek), but in American English its name is zee ziː, analogous to the names for B, C, D, etc.
English orthographyEnglish orthography is the writing system used to represent spoken English, allowing readers to connect the graphemes to sound and to meaning. It includes English's norms of spelling, hyphenation, capitalisation, word breaks, emphasis, and punctuation. Like the orthography of most world languages, English orthography has a broad degree of standardisation. This standardisation began to develop when movable type spread to England in the late 15th century.
Eddy currentIn electromagnetism, eddy currents (also called Foucault's currents) are loops of electric current induced within conductors by a changing magnetic field in the conductor according to Faraday's law of induction or by the relative motion of a conductor in a magnetic field. Eddy currents flow in closed loops within conductors, in planes perpendicular to the magnetic field. They can be induced within nearby stationary conductors by a time-varying magnetic field created by an AC electromagnet or transformer, for example, or by relative motion between a magnet and a nearby conductor.
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