Hypertension and Vascular Research Unit, Lady Davis Institute for Medical Research, Montreal, Québec, Canada.
Department of Cardiology, Ehime Prefectural Central Hospital, Matsuyama, Japan.
J Vasc Res. 2021;58(6):379-387. doi: 10.1159/000516842. Epub 2021 Jun 28.
Pressurized myography is useful for the assessment of small artery structures and function. However, this procedure requires technical expertise for sample preparation and effort to choose an appropriate sized artery. In this study, we developed an automatic artery/vein differentiation and a size measurement system utilizing machine learning algorithms.
We used 654 independent mouse mesenteric artery images for model training. The model yielded an Intersection-over-Union of 0.744 ± 0.031 and a Dice coefficient of 0.881 ± 0.016. The vessel size and lumen size calculated from the predicted vessel contours demonstrated a strong linear correlation with manually determined vessel sizes (R = 0.722 ± 0.048, p < 0.001 for vessel size and R = 0.908 ± 0.027, p < 0.001 for lumen size). Last, we assessed the relation between the vessel size before and after dissection using a pressurized myography system. We observed a strong positive correlation between the wall/lumen ratio before dissection and the lumen expansion ratio (R = 0.832, p < 0.01). Using multivariate binary logistic regression, 2 models estimating whether the vessel met the size criteria (lumen size of 160-240 μm) were generated with an area under the receiver operating characteristic curve of 0.761 for the upper limit and 0.747 for the lower limit.
The U-Net-based image analysis method could streamline the experimental approach.
加压血管造影术可用于评估小动脉结构和功能。然而，该程序需要技术专业知识来进行样本准备，并需要努力选择合适大小的动脉。在这项研究中，我们利用机器学习算法开发了一种自动动脉/静脉区分和尺寸测量系统。
我们使用了 654 个独立的鼠标肠系膜动脉图像进行模型训练。该模型的交并比为 0.744 ± 0.031，骰子系数为 0.881 ± 0.016。从预测的血管轮廓计算出的血管尺寸和管腔尺寸与手动确定的血管尺寸显示出很强的线性相关性（R = 0.722 ± 0.048，p < 0.001 用于血管尺寸，R = 0.908 ± 0.027，p < 0.001 用于管腔尺寸）。最后，我们使用加压血管造影系统评估了血管在解剖前后的大小关系。我们观察到在解剖前的管壁/管腔比与管腔扩张比之间存在很强的正相关关系（R = 0.832，p < 0.01）。使用多元二项逻辑回归，生成了两个估计血管是否符合尺寸标准（管腔尺寸为 160-240μm）的模型，上限的受试者工作特征曲线下面积为 0.761，下限的面积为 0.747。
基于 U-Net 的图像分析方法可以简化实验方法。
