subtraction


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subtraction

 [sub-trak´shun]
the photographic or electronic removal of overlying structures from radiologic images.

sub·trac·tion

(sŭb-trak'shŭn),
A technique used to enhance detectability of opacified anatomic structures on radiographic or scintigraphic images; a negative of an image made before introduction of contrast medium or radionuclide is photographically or electronically removed from a later image; commonly used in cerebral angiography.
See also: digital subtraction angiography, mask.

sub·trac·tion

(sŭb-trak'shŭn)
A technique used to enhance detectability of opacified anatomic structures on radiographic or scintigraphic images; a negative of an image made before introduction of contrast medium or radionuclide is photographically or electronically removed from a later image; commonly used in cerebral angiography.
See also: digital subtraction angiography, mask

subtraction

(sŭb-trak′shŏn)
Removal of undesired overlying structures from a radiographical image by superimposing an image taken before the addition of contrast material with one taken after.
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