Assessment of stenosis severity using a novel method to estimate spatial and temporal variations of blood flow velocity in biplane coronarography

摘要: The authors present a novel method to estimate absolute blood flow velocity in coronary arteries from biplane angiograms. Spatial and temporal variations are derived giving simultaneously direct geometric an indirect functional index of stenosis severity, ratio reserve. No prior assumption concerning geometry is made. Deformable models used track artery segment dynamically three dimensions. A densitometric map obtained by summing densities across sections at every position along the previously calculated path time cardiac cycle. An advection relationship between density observed. spatiotemporal solution nonlinear least-squares scheme. simulation protocol based on simple conformations properties assess numerical stability immunity towards noise. Predicted results for compared with intracoronary Doppler recordings test model assumptions basal state hyperaemia examinations same patient. was accurate within 3% simulated additive Gaussian noise standard deviation 0.14. limits agreement angiographic velocities were -11.4 peak value (basal state) -16.8 (hyperaemia), corresponding 18 3.5% errors average values 16% error To summarize, derivation its presented. Simulated experimental corroborate validity schemes support clinical applicability.