Validation of volume blood flow measurements using three-dimensional distance-concentration functions derived from digital x-ray angiograms.

D J Hawkes; A M Seifalian; A C Colchester; N Iqbal; C R Hardingham; C F Bladin; K E Hobbs

doi:10.1097/00004424-199404000-00009

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PubMed · 8034449

Validation of volume blood flow measurements using three-dimensional distance-concentration functions derived from digital x-ray angiograms.

D J Hawkes·A M Seifalian·A C Colchester·N Iqbal·C R Hardingham·C F Bladin·K E Hobbs

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Abstract

RATIONALE AND OBJECTIVES: The authors present phantom validation of a method for computing pulsatile flow waveforms in arterial vessels from high-frame-rate biplane x-ray angiograms. METHODS: The three-dimensional course of a blood vessel is constructed from biplane digital x-ray angiograms. A parametric image of contrast mass versus time and true three-dimensional path length is generated. Adjacent contrast mass-distance profiles are matched to compute instantaneous velocity, which is multiplied by cross-sectional area to yield volume flow. An electromagnetic flowmeter was used to validate flow estimates in a phantom consisting of 150-mm tubes 3, 4, and 6 mm in diameter, orientated 15 degrees, 30 degrees, and 35 degrees to the imaging plane, with flow rates and waveforms expected in vivo. RESULTS: Mean and peak flows were accurate to within 9% and 10%, respectively, for velocities of less than 1 meter/second at a frame rate of 25 frames per second. CONCLUSIONS: A practical method for computing highly pulsatile flow waveforms in vivo in tortuous vessels is presented.

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Algorithms Angiography, Digital Subtraction Blood Flow Velocity Blood Vessels Humans Image Processing, Computer-Assisted Models, Cardiovascular Models, Structural Pulsatile Flow Journal Article Research Support, Non-U.S. Gov't

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D J Hawkes, A M Seifalian, A C Colchester, N Iqbal, C R Hardingham, C F Bladin, K E Hobbs. 1994. Validation of volume blood flow measurements using three-dimensional distance-concentration functions derived from digital x-ray angiograms.. https://doi.org/10.1097/00004424-199404000-00009

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