Angiography, Digital Subtraction

**Definition:** 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 digitized 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.

**Tree numbers:** - E01.370.350.600.350.700.060 - E01.370.350.700.060.060 - E01.370.350.700.700.060 - E01.370.350.760.060 - E01.370.370.050.060

**Synonyms:** - Digital Subtraction Angiography - Subtraction Angiography, Digital