Fenech Marianne, Le Andy Vinh, Salame Maya, Gliah Omemah, Chartrand Camille
Mechanical Engineering Department, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada.
Mechanical Engineering Department, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada; Centre de Biochimie Structurale, CNRS 5048-INSERM UMR 1054, University of Montpellier, 34090 Montpellier, France.
Microvasc Res. 2023 May;147:104496. doi: 10.1016/j.mvr.2023.104496. Epub 2023 Feb 3.
In microcirculation, red blood cells (RBCs) tend to migrate toward the centre of the vessel leaving a region of a cell depleted layer or cell-free layer (CFL) at the vessel wall and a core of RBCs at the centre. This heterogenous distribution of cells has an effect on the blood apparent viscosity and the exchanges of gases and nutrients between the RBCs and the vessel. Understanding the formation of the CFL and obtaining accurate measurement of it is paramount for furthering development of devices such as drug administration. This paper presents a general semi-automatic method to quantify the thickness of the CFL for different channel geometries and image quality. It enables the use of a method based on intensity, a method using the gradient of the intensity, or a method based on spatiotemporal variation. The main features are reported, the performance is demonstrated on experimentally obtained image sets and accuracy is validated using synthetic images with known CFL thickness. A pure automatic detection is limited by the most visually correct using the spatiotemporal method, however proposed thresholding through automatic detection allows for quality controls through manual adjustments. With a semi-automatic approach RBC core variability between 3 % to 8 % was found when the test user was tasked with repeating the analysis of the same set. The presented method provides, users without programming ability with a user-friendly interface that can extract CFL automatically with quality control through manual adjustments.
在微循环中，红细胞（RBC）倾向于向血管中心迁移，在血管壁处留下一个细胞耗尽层或无细胞层（CFL）区域，而在中心处则形成一个红细胞核心。这种细胞的异质分布会影响血液表观粘度以及红细胞与血管之间的气体和营养物质交换。了解CFL的形成并对其进行准确测量对于推进诸如药物给药等设备的开发至关重要。本文提出了一种通用的半自动方法，用于量化不同通道几何形状和图像质量下CFL的厚度。它可以使用基于强度的方法、使用强度梯度的方法或基于时空变化的方法。报告了主要特征，在实验获得的图像集上展示了性能，并使用具有已知CFL厚度的合成图像验证了准确性。纯自动检测受时空方法在视觉上最正确的限制，然而通过自动检测提出的阈值化允许通过手动调整进行质量控制。当测试用户被要求重复分析同一组时，采用半自动方法发现红细胞核心变异性在3%至8%之间。所提出的方法为没有编程能力的用户提供了一个用户友好的界面，该界面可以通过手动调整进行质量控制来自动提取CFL。
