Pereira Sujith, Reeves Jonathan, Birch Malcolm, Finton-James Sakthi, Verma Komal, Krug Robert, Sinha Ajay, Kempley Stephen
Neonatal Unit, Homerton University Hospital NHS Foundation Trust, London, UK.
Centre for Genomics and Child Health, Blizard Institute, Barts and The London School of Medicine and Dentistry, London, UK.
Ultrasound. 2020 Aug;28(3):145-154. doi: 10.1177/1742271X20902189. Epub 2020 Feb 3.
Cerebral blood flow is increasingly monitored in preterm infants. Doppler ultrasound of the carotid artery is a widely available method but is operator dependent. Our aim was to design and produce a realistic flow phantom model of the carotid artery of preterm infants.
Data from cerebral blood flow measurements using Doppler ultrasound of the right common carotid artery from 21 premature newborn infants were used to produce a Doppler flow phantom model with three different vessel diameters. Vessel diameter, continuous and pulsatile flow volume measurements were performed by two blinded observers (with more than eight and 20 years of experience).
Vessel diameter measurements using the phantom were underestimated by 7%. Continuous flow volume measurements were overestimated by 7% by both observers (observer 1 mean difference 1.5 ± 1.96 SD -3.3 to 6.3 ml/min versus observer 2, 1.9 ± 1.96 SD -3.6 to 7.4 ml/min). Pulsatile flow measurements were overestimated by 12.6% by observer 1 (2.7 ± 1.96 SD -0.6 to 5.9 ml/min) and by 7.8% by observer 2 (1.7 ± 1.96 SD -1.6 to 4.9 ml/min). There was good interobserver and intraobserver reliability for the majority of measurements using continuous and pulsatile flow.
It is feasible to produce a realistic flow phantom model of the neonatal carotid artery of preterm infants. Diameter measurements were underestimated and flow measurements were overestimated. These errors fell within acceptable limits for in vivo measurements. If these limitations were related to materials, this could be explored using a wall-less model. The flow phantom could be utilised for research and training clinicians in measuring cerebral blood flow using the carotid artery in this vulnerable group of infants.
对早产儿脑血流量的监测越来越受到关注。颈动脉多普勒超声是一种广泛应用的方法，但它依赖于操作人员。我们的目的是设计并制作一个逼真的早产儿颈动脉血流模拟模型。
使用21例早产新生儿右侧颈总动脉的多普勒超声进行脑血流量测量的数据，制作了具有三种不同血管直径的多普勒血流模拟模型。由两名不知情的观察者（分别有超过8年和20年的经验）进行血管直径、连续和搏动血流量的测量。
使用模拟模型进行的血管直径测量低估了7%。两名观察者对连续血流量的测量均高估了7%（观察者1的平均差异为1.5±1.96标准差，范围为-3.3至6.3毫升/分钟；观察者2为1.9±1.96标准差，范围为-3.6至7.4毫升/分钟）。观察者1对搏动血流量的测量高估了12.6%（2.7±1.96标准差，范围为-0.6至5.9毫升/分钟），观察者2高估了7.8%（1.7±1.96标准差，范围为-1.6至4.9毫升/分钟）。对于大多数使用连续和搏动血流的测量，观察者间和观察者内的可靠性良好。
制作逼真的早产儿新生儿颈动脉血流模拟模型是可行的。直径测量被低估，血流测量被高估。这些误差在体内测量的可接受范围内。如果这些限制与材料有关，可以使用无壁模型进行探索。该血流模拟模型可用于研究以及培训临床医生对这一脆弱婴儿群体使用颈动脉测量脑血流量。
