2D digital subtraction angiography (DSA) is utilized qualitatively to assess blood velocity changes that occur during arterial interventions. Quantitative angiographic metrics, such as blood velocity, could be used to standardize endpoints during angiographic interventions. To assess the accuracy and precision of a quantitative 2D DSA (qDSA) technique and to determine its feasibility for in vivo measurements of blood velocity. A quantitative DSA technique was developed to calculate intra-procedural blood velocity. In vitro validation was performed by comparing velocities from the qDSA method and an ultrasonic flow probe in a bifurcation phantom. Parameters of interest included baseline flow rate, contrast injection rate, projection angle, and magnification. In vivo qDSA analysis was completed in five different branches of the abdominal aorta in two 50 kg swine and compared to 4D Flow MRI. Linear regression, Bland-Altman, Pearson’s correlation coefficient and chi squared tests were used to assess the accuracy and precision of the technique. In vitro validation showed strong correlation between qDSA and flow probe velocities over a range of contrast injection and baseline flow rates (slope = 1.012, 95% CI [0.989,1.035], Pearson’s r = 0.996, p < .0001). The application of projection angle and magnification corrections decreased variance to less than 5% the average baseline velocity (p = 0.999 and p = 0.956, respectively). In vivo validation showed strong correlation with a small bias between qDSA and 4D Flow MRI velocities for all five abdominopelvic arterial vessels of interest (slope = 1.01, Pearson’s r = 0.880, p = <.01, Bias = 0.117 cm/s). The proposed method allows for accurate and precise calculation of blood velocities, in near real-time, from time resolved 2D DSAs.

中文翻译：

---

使用时间分辨二维数字减影血管造影术内血流速度定量技术

2D 数字减影血管造影 (DSA) 用于定性评估动脉介入期间发生的血流速度变化。定量血管造影指标，例如血流速度，可用于在血管造影干预期间标准化终点。评估定量 2D DSA (qDSA) 技术的准确性和精密度，并确定其在体内测量血流速度的可行性。开发了一种定量 DSA 技术来计算程序内血流速度。通过比较来自 qDSA 方法和分叉体模中的超声波流量探头的速度进行体外验证。感兴趣的参数包括基线流速、造影剂注射速率、投影角度和放大率。在两只 50 kg 猪的腹主动脉的五个不同分支中完成了体内 qDSA 分析，并与 4D Flow MRI 进行了比较。线性回归、Bland-Altman、Pearson 相关系数和卡方检验用于评估该技术的准确性和精密度。体外验证显示，qDSA 和流量探头速度在一系列造影剂注射和基线流速之间具有很强的相关性（斜率 = 1.012, 95% CI [0.989,1.035]，Pearson 的 r = 0.996，p < .0001）。投影角度和放大率校正的应用将方差降低到平均基线速度的 5% 以下（分别为 p = 0.999 和 p = 0.956）。体内验证显示，对于所有五个感兴趣的腹盆腔动脉血管（斜率 = 1.01，Pearson 的 r = 0.880，p = <.01，偏差 = 0.117 cm/s）。所提出的方法允许从时间分辨的 2D DSA 近乎实时地准确和精确地计算血流速度。