digital subtraction angiography

(redirected from Angiography, digital subtraction)
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radiography of vessels of the body after injection of contrast material; see also arteriography, lymphangiography, and phlebography. Called also vasography.
digital subtraction angiography radiographic visualization of blood vessels, with images produced by subtracting background structures and enhancing the contrast of those areas that change in density between a preliminary “mask” image and subsequent images.

dig·i·tal sub·trac·tion an·gi·og·ra·phy (DSA),

computer-assisted radiographic angiography that permits visualization of vascular structures without superimposed bone and soft tissue densities; subtraction of images made before and after contrast injection removes structures not enhanced by the contrast medium. Other image processing can be performed. Contrast material may be injected intravenously or in a lower-than-usual amount intraarterially.

digital subtraction angiography (DSA)

a method in which radiographic images of blood vessels filled with contrast material are digitized and then subtracted from images obtained before administration of the material. The method increases the contrast between the vessels and the background.

digital subtraction angiography

Radiology A diagnostic technique that uses video equipment and computers to enhance images obtained with conventional angiography

dig·i·tal sub·trac·tion an·gi·og·ra·phy

(DSA) (dij'i-tăl sŭb-trak'shŭn an'jē-og'ră-fē)
Computer-assisted radiographic angiography permitting visualization of vascular structures without superimposed bone and soft tissue density; images made before and after contrast injection allow subtraction (separation and removal) of opacities not enhanced by the contrast medium Other image-processing can be performed. Contrast material may be injected intravenously or in lower-than-usual amounts intraarterially.
See: digital radiography

digital subtraction angiography

A method of imaging blood vessels that eliminates unwanted detail. Two digitized images are made, before and after injecting a radio-opaque dye. A negative image of one is then combined with the other, so that only differences between the two show up-in this case the dye in the vessels.
References in classic literature ?
Her benefactors had seen fit to ignore mention of her strange past, and so she passed as their ward whose antecedents not having been mentioned were not to be inquired into.
The 'Deus ex Machina' should be employed only for events external to the drama,--for antecedent or subsequent events, which lie beyond the range of human knowledge, and which require to be reported or foretold; for to the gods we ascribe the power of seeing all things.
It resulted from these antecedents that everyone entered heartily into the purpose for which they met; besides, it would not be unlikely that they would have an opportunity of playing either the cardinal or his people an ill turn, and for such expeditions these worthy gentlemen were always ready.
Your brother told me that my antecedents and occupations were against me; that your family stands, somehow, on a higher level than I do.
The Lascar was known to be a man of the vilest antecedents, but as, by Mrs.
Let us put it down to his deplorable antecedents and education, if you wish.
Manson Mingott's English son-in-law, the banker, and had speedily made himself an important position in the world of affairs; but his habits were dissipated, his tongue was bitter, his antecedents were mysterious; and when Medora Manson announced her cousin's engagement to him it was felt to be one more act of folly in poor Medora's long record of imprudences.
By discarding a claim to knowledge of the ultimate purpose, we shall clearly perceive that just as one cannot imagine a blossom or seed for any single plant better suited to it than those it produces, so it is impossible to imagine any two people more completely adapted down to the smallest detail for the purpose they had to fulfill, than Napoleon and Alexander with all their antecedents.
That I have some claim to the exercise of a veto here, would not, I believe, be denied by any reasonable person cognizant of the relations between us: relations which, though thrown into the past by your recent procedure, are not thereby annulled in their character of determining antecedents.
The product of a large store of reading has been here secreted anew for the reader who desires to see, in bird's-eye view, the light and shade of a long and varied period of poetic literature, by way of preparation for Shakespeare, [9] (with a full essay upon whom the volume closes,) explaining Shakespeare, so far as he can be explained by literary antecedents.
Her fear of the man was gradually departing, and she was full of a thousand unsatisfied curiosities as to his plans for the future in so far as they related to her, as well as more personal questions regarding himself, since she could not but wonder as to his antecedents and his strange and solitary life in the jungle, as well as his friendly intercourse with the savage apes among which she had found him.
It would be easy to find a thousand places where your antecedents would be neither known nor questioned.