CT number


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number

 [num´ber]
a symbol, as a figure or word, expressive of a certain value or a specified quantity determined by count.
atomic number (Z) a number expressive of the number of protons in an atomic nucleus, or the positive charge of the nucleus expressed in terms of the electronic charge.
Avogadro's number (N) (NA) the number of molecules in one mole of a substance: 6.023 × 1023. Called also Avogadro's constant.
CT number the density assigned to a voxel in a CAT scan on an arbitrary scale on which air has a density −1000; water, 0; and compact bone +1000. See also hounsfield unit.
mass number (A) the number of nucleons (protons plus neutrons) in the atom of a nuclide; generally indicated by a superscript preceding the symbol of a chemical element (e.g., 131I), denoting a specific isotope.
oxidation number a number assigned to each atom in a molecule or ion that represents the number of electrons theoretically gained (positive oxidation numbers) or lost (negative numbers) in converting the atom to the elemental form.

CT num·ber

a normalized value of the calculated x-ray absorption coefficient of a pixel (picture element) in a computed tomogram, expressed in Hounsfield units, where the CT number of air is -1000 and that of water is 0.
Synonym(s): Hounsfield number

CT number

Hounsfield,

Godfrey N., English electronics engineer and Nobel laureate, 1919–.
Hounsfield number - a normalized value of the calculated x-ray absorption coefficient of a pixel in a computed tomogram. Synonym(s): CT number
Hounsfield unit - a normalized index of x-ray attenuation used in CT imaging.

CT

computed tomography.

CT number
the density assigned to a voxel in a CT (computed tomography) scan on an arbitrary scale on which air has a density −1000; water, 0; and compact bone +1000. CT numbers are sometimes said to be expressed in 'Hounsfield units'.
References in periodicals archive ?
Therefore, wood CT numbers computed using Equation [1] are generally less than zero.
In this study, all of the CT numbers were determined based on Equation [2].
The linear least squares fitting (Worthing and Geffner 1943) was performed to establish the linear relationship between the measured densities of the green discs and their corresponding average values of the CT numbers.
The window width is set to define the range of CT numbers to be displayed.