Ruisch Janna, de Bakker Joosje M K, van Helvert Majorie, Schoonbrood Maxime J P, Groot Jebbink Erik, Holewijn Suzanne, Reijnen Michel M P J, de Korte Chris L, Saris Anne E C M
Medical Ultrasound Imaging Centre, Department of Medical Imaging, Radboud University Medical Centre, Nijmegen, the Netherlands; Department of Vascular Surgery, Rijnstate Hospital, Arnhem, the Netherlands.
Medical Ultrasound Imaging Centre, Department of Medical Imaging, Radboud University Medical Centre, Nijmegen, the Netherlands.
Ultrasound Med Biol. 2025 Jun;51(6):969-976. doi: 10.1016/j.ultrasmedbio.2025.02.008. Epub 2025 Mar 6.
Ultrasound-based velocity vector imaging (US-VVI) is a promising technique to gain insight into complex blood flow patterns that play an important role in atherosclerosis. However, in vivo validation of the 2-D velocity vector fields in the carotid bifurcation, using an adaptive velocity compounding method, is lacking. Its performance was validated in vivo against 4-D flow magnetic resonance imaging (MRI). Furthermore, the repeatability of US-VVI was determined.
High frame rate US-VVI, which was repeated three times, and 4-D flow MRI data were acquired of the carotid bifurcation of 20 healthy volunteers. A semiautomatic registration of all US-VVI (n = 60) and 4-D flow MRI data was performed. The 2-D velocity vector fields were compared using cosine similarity and the root-mean-square error of the velocity magnitude. Temporal velocity profiles from the common carotid artery and internal carotid artery were compared. The interobserver and intraobserver agreement of US-VVI was determined for peak systolic velocities and end-diastolic velocities.
The registration was successful in 83% of cases. The 2-D velocity vector fields matched well between modalities, which is supported by high cosine similarities and low root-mean-square error of the velocity magnitudes. Temporal profiles showed high resemblance, with similarity indices of 0.87 and 0.80, and mean peak systolic velocity differences of 0.91 and 7.9 cm/s in the common carotid artery and internal carotid artery, respectively. Good repeatability of US-VVI was shown with a highest bias and standard deviation of 1.7 and 11.7 cm/s, respectively.
Good agreements were found of both vector angles and velocity magnitudes between US-VVI and 4-D flow MRI. Given the high spatiotemporal resolution, US-VVI enables the capture of small recirculating regions of short duration that are missed by 4-D flow MRI.
基于超声的速度向量成像（US-VVI）是一种很有前景的技术，可用于深入了解在动脉粥样硬化中起重要作用的复杂血流模式。然而，目前缺乏使用自适应速度复合方法对颈动脉分叉处二维速度向量场进行体内验证的研究。本研究在体内将其性能与四维血流磁共振成像（MRI）进行了验证。此外，还确定了US-VVI的可重复性。
对20名健康志愿者的颈动脉分叉处进行了高帧率US-VVI检查，重复3次，并采集了四维血流MRI数据。对所有US-VVI（n = 60）和四维血流MRI数据进行了半自动配准。使用余弦相似度和速度大小的均方根误差比较二维速度向量场。比较了颈总动脉和颈内动脉的时间速度剖面。确定了US-VVI在收缩期峰值速度和舒张末期速度方面的观察者间和观察者内一致性。
83%的病例配准成功。两种模态之间的二维速度向量场匹配良好，这得到了高余弦相似度和低速度大小均方根误差的支持。时间剖面显示出高度相似性，颈总动脉和颈内动脉的相似性指数分别为0.87和0.80，平均收缩期峰值速度差异分别为0.91和7.9 cm/s。US-VVI显示出良好的可重复性，最高偏差和标准差分别为1.7和11.7 cm/s。
US-VVI与四维血流MRI在向量角度和速度大小方面均具有良好的一致性。鉴于高时空分辨率，US-VVI能够捕捉到四维血流MRI遗漏的持续时间短的小再循环区域。
