PURPOSE: In this paper, a method for the estimation of arterial hemodynamic flow from x-ray video densitometry data is proposed and validated using an in vitro setup. METHODS: The method is based on the acquisition of three-dimensional rotational angiography and digital subtraction angiography sequences. A modest contrast injection rate (between 1 and 4 ml/s) leads to a contrast density that is modulated by the cardiac cycle, which can be measured in the x-ray signal. An optical flow based approach is used to estimate the blood flow velocities from the cyclic phases in the x-ray signal. RESULTS: The authors have validated this method in vitro, and present three clinical cases. The in vitro experiments compared the x-ray video densitometry results with the gold standard delivered by a flow meter. Linear correlation analysis and regression fitting showed that the ideal slope of 1 and intercept of 0 were contained within the 95 percentile confidence interval. The results show that a frame rate higher than 50 Hz allows measuring flows in the range of 2 ml/s to 6 ml/s within an accuracy of 5%. CONCLUSIONS: The in vitro and clinical results indicate that it is feasible to estimate blood flow in routine interventional procedures. The availability of an x-ray based method for quantitative flow estimation is particularly clinically useful for intra-cranial applications, where other methods, such as ultrasound Doppler, are not available.
PURPOSE: In this paper, a method for the estimation of arterial hemodynamic flow from x-ray video densitometry data is proposed and validated using an in vitro setup. METHODS: The method is based on the acquisition of three-dimensional rotational angiography and digital subtraction angiography sequences. A modest contrast injection rate (between 1 and 4 ml/s) leads to a contrast density that is modulated by the cardiac cycle, which can be measured in the x-ray signal. An optical flow based approach is used to estimate the blood flow velocities from the cyclic phases in the x-ray signal. RESULTS: The authors have validated this method in vitro, and present three clinical cases. The in vitro experiments compared the x-ray video densitometry results with the gold standard delivered by a flow meter. Linear correlation analysis and regression fitting showed that the ideal slope of 1 and intercept of 0 were contained within the 95 percentile confidence interval. The results show that a frame rate higher than 50 Hz allows measuring flows in the range of 2 ml/s to 6 ml/s within an accuracy of 5%. CONCLUSIONS: The in vitro and clinical results indicate that it is feasible to estimate blood flow in routine interventional procedures. The availability of an x-ray based method for quantitative flow estimation is particularly clinically useful for intra-cranial applications, where other methods, such as ultrasound Doppler, are not available.
Authors: Marco Boegel; Sonja Gehrisch; Thomas Redel; Christopher Rohkohl; Philip Hoelter; Arnd Doerfler; Andreas Maier; Markus Kowarschik Journal: Int J Comput Assist Radiol Surg Date: 2016-03-26 Impact factor: 2.924
Authors: O Brina; R Ouared; O Bonnefous; F van Nijnatten; P Bouillot; P Bijlenga; K Schaller; K-O Lovblad; T Grünhagen; D Ruijters; V Mendes Pereira Journal: AJNR Am J Neuroradiol Date: 2014-07-31 Impact factor: 3.825
Authors: V M Pereira; O Bonnefous; R Ouared; O Brina; J Stawiaski; H Aerts; D Ruijters; A P Narata; P Bijlenga; K Schaller; K-O Lovblad Journal: AJNR Am J Neuroradiol Date: 2012-11-01 Impact factor: 3.825
Authors: Jan Sedlacik; Andreas Frölich; Johanna Spallek; Nils D Forkert; Tobias D Faizy; Franziska Werner; Tobias Knopp; Dieter Krause; Jens Fiehler; Jan-Hendrik Buhk Journal: PLoS One Date: 2016-08-05 Impact factor: 3.240