X-ray videodensitometric methods for blood flow and velocity measurement: A critical review of literature

Blood flow rate and velocity are important parameters for the study of vasc ular systems, and for the diagnosis, monitoring and evaluation of treatment of cerebro- and cardiovascular disease. For rapid imaging of cerebral and cardiac blood vessels, digital x-ray subtraction angiography has numerous a dvantages over other modalities. Roentgen-videodensitometric techniques mea sure blood flow and velocity from changes of contrast material density in x -ray angiograms. Many roentgenvideodensitometric flow measurement methods c an also be applied to CT, MR and rotational angiography images. Hence, roen tgen-videodensitometric blood flow and velocity measurement from digital x- ray angiograms represents an important research topic. This work contains a critical review and bibliography surveying current and old developments in the field. We present an extensive survey of English-language publications on the subject and a classification of published algorithms. We also prese nt descriptions and critical reviews of these algorithms. The algorithms ar e reviewed with requirements imposed by neuro- and cardiovascular clinical environments in mind. (C) 2000 American Association of Physicists in Medici ne. [S0094-2405(00)01409-7].