Measurement of absolute flow rate in vessels using a stereoscopic DSA system

Abstract

We used a stereoscopic digital subtraction angiography (DSA) system to measure absolute blood flow rates in vessels. The magnification factor and the three-dimensional orientation of a selected vessel are obtained from automated analysis of stereoscopic DSA images. The cross-sectional area of the vessel is determined from the vessel diameter, which is measured with an iterative deconvolution technique. The time required for fluid to flow through a selected segment of a vessel is determined from the automated analysis of contrast medium 'time-density' curves. The effectiveness of these combined techniques was demonstrated in measurement of rates of both continuous and pulsatile flow in a vessel phantom, with the actual flow rate calibrated volumetrically or by an electromagnetic flowmeter. We have obtained accuracies in measured flow rates of approximately 5% and 18% for continuous and pulsatile flow respectively.

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

“…17 The resulting bolus transport time approach, usually known as peak-to-peak transit time, was used for the measurement of blood flow and velocity in carotid arteries, [26][27][28][29] in intracranial aneurysms, 28 in coronary arteries, 30 in abdominal aorta, 31,32 in other human arteries [33][34][35][36] and for measurement of regional coronary blood flow. [37][38][39][40] The reported applications of this technique include in vitro, 26,31,32,35,[41][42][43] in experimental animals 32,38,39 and in patients. 26,27,30,31,33,34,35,37,40 ͑2͒ Time-of-leading half-peak opacification-the bolus is considered to have arrived when the time-density curve achieves half of its peak density for the first time, as shown in Fig.…”

Model-based blood flow quantification from rotational angiography

“…All existing approaches are based on analysing changes in the X-ray image intensity due to changes of the contrast agent concentration. Shpilfoygel et al (2000) have given a comprehensive review of established techniques, which include: techniques based on bolus tracking using time intensity curves (TICs) at different sites along a vessel (Rutishauser et al, 1970;Yerushalmi and Itzchak, 1976;Silverman and Rosen, 1977;Hoehne et al, 1978;Kruger et al, 1983;Fencil et al, 1989;Schmitt et al, 2002;Schmitt et al, 2005;Bogunovic and Loncaric, 2006); techniques based on distance intensity curves (DICs) at different points in time (Colchester et al, 1986;Seifalian et al, 1989;Hoffmann et al, 1991;Brunt et al, 1992;Shpilfoygel et al, 1998;Bladin et al, 1996;Rhode et al, 2005); techniques based on optical flow (Fitzpatrick, 1985;Efron et al, 1978;Amini et al, 1993;Imbert et al, 1995;Huang et al, 1997;Rhode et al, 2001); and techniques based on first pass distribution analysis (Molloi et al, 1998(Molloi et al, , 2004.…”

<title>Densitometric measurement of blood flow application to stenosis quantification</title>

“…Extending the computer program to take into account in plane vessel rotation is straightforward. Axial (perpendicular to the image plane) rotation requires a complementary view to estimate it : it may significantly degrades the accuracy [4,9]. Our work deals with steady flows, while blood flow is time varying by essence.…”

“…Finally, a discrete formulation of F(z) is required. (4) where Lx Is the pixel dimension in the x direction (it depends on the II input field size), -C is the temporal sampling path (it depends on frame acquisition rate). For Eq.…”