| angiography, digital subtraction | A method of delineating blood vessels by subtracting a tissue background image from an image of tissue plus intravascular contrast material that attenuates the X-ray photons. The background image is determined from a digitised image taken a few moments before injection of the contrast material. The resulting angiogram is a high-contrast image of the vessel. This subtraction technique allows extraction of a high-intensity signal from the superimposed background information. The image is thus the result of the differential absorption of X-rays by different tissues. (12 Dec 1998) |
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| biplane angiography | Synchronous angiocardiography in two planes at right angles to each other or in two orthogonal planes. (05 Mar 2000) |
| radionuclide angiography | The measurement of visualization by radiation of any organ after a radionuclide has been injected into its blood supply. It is used to diagnose heart, liver, lung, and other diseases and to measure the function of those organs, except renography, for which radioisotope renography is available. (12 Dec 1998) |
| magnetic resonance angiography | Non-invasive method of vascular imaging and determination of internal anatomy without injection of contrast media or radiation exposure. The technique is used especially in cerebral angiography as well as for studies of other vascular structures. (12 Dec 1998) |
| magnification angiography | Enhanced imaging of small blood vessels using an increased distance from subject to film, as in magnification radiography. (05 Mar 2000) |
| cerebral angiography | Radiography of the vascular system of the brain after injection of a contrast medium. (12 Dec 1998) |
| MR angiography | Imaging of blood vessels using special MR sequences which enhance the signal of flowing blood and suppress that from other tissues. Synonym: magnetic resonance angiography. (05 Mar 2000) |
| coronary angiography | Radiography of the vascular system of the heart muscle after injection of a contrast medium. (12 Dec 1998) |
| scintigraphic angiography | The measurement of visualization by radiation of any organ after a radionuclide has been injected into its blood supply. It is used to diagnose heart, liver, lung, and other diseases and to measure the function of those organs, except renography, for which radioisotope renography is available. (12 Dec 1998) |
| selective angiography | <procedure, radiology> Angiography in which visualization is improved by concentrating the contrast medium in the region to be studied by injection through a catheter positioned in a regional artery. (05 Mar 2000) |
| digital subtraction angiography | Computer-assisted roentgenographic 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 amount intra-arterially. (05 Mar 2000) |
| interventional angiography | <cardiology, surgery> The surgical repair of a blood vessel. A balloon angioplasty is a noninvasive procedure where a balloon-tipped catheter is introduced into a diseased blood vessel. As the balloon is inflated, the vessel opens further allowing for improved flow of blood. (12 Nov 1997) |
| therapeutic angiography | Use of angiographic catheters that have been modified to reduce or increase regional blood flow, or to deliver medicinal agents; interventional therapeutic angiography. See: angioplasty, balloon catheter, interventional angiography. (05 Mar 2000) |
| fluorescein angiography | <procedure> The process of taking X-rays of blood vessels that have been injected with a special dye. The dye allows to person viewing the X-ray to see the blood vessels. (13 Nov 1997) |