Volume blood flow waveforms measurements from quantitative X-ray angiographic data with aid of 3-dimensional reconstructions

Biplane images are recorded using digital angiography. The X-ray gantry geometry is established and the 3-dimensional (3D) orientation and calibre of a selected vessel computed. A "parametric" image is generated, in which the image grey level represents contrast material as a function of time and distance along a vessel segment. Adjacent concentration-distance profiles in parametric images are re-registered to minimise the mean sum of squares of differences. The distance translated per frame interval multiplied by vessel cross section gives volume flow. This technique has heen validated to be accurate to within 5% for mean flow ranging from 176 to 689 ml/min in a blood vessel phantom.