Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA.
Department of Ophthalmology and Visual Science, Medical College of Wisconsin, Milwaukee, WI, USA.
Transl Vis Sci Technol. 2021 Aug 2;10(9):19. doi: 10.1167/tvst.10.9.19.
To develop and test a non-contact, contrast-free, retinal laser speckle contrast imaging (LSCI) instrument for use in small rodents to assess vascular anatomy, quantify hemodynamics, and measure physiological changes in response to retinal vascular dysfunction over a wide field of view (FOV).
A custom LSCI instrument capable of wide-field and non-contact imaging in small rodents was constructed. The effect of camera gain, laser power, and exposure duration on speckle contrast variance was standardized before the repeatability of LSCI measurements was determined in vivo. Finally, the ability of LSCI to detect alterations in local and systemic vascular function was evaluated using a laser-induced branch retinal vein occlusion and isoflurane anesthesia model, respectively.
The LSCI system generates contrast-free maps of retinal blood flow with a 50° FOV at >376 frames per second (fps) and under a short exposure duration (>50 µs) with high reliability (intraclass correlation R = 0.946). LSCI was utilized to characterize retinal vascular anatomy affected by laser injury and longitudinally measure alterations in perfusion and blood flow profile. Under varied doses of isoflurane, LSCI could assess cardiac and systemic vascular function, including heart rate, peripheral resistance, contractility, and pulse propagation.
We present a LSCI system for detecting anatomical and physiological changes in retinal and systemic vascular health and function in small rodents.
Detecting and quantifying early anatomical and physiological changes in vascular function in animal models of retinal, systemic, and neurodegenerative diseases could strengthen our understanding of disease progression and enable the identification of new prognostic and diagnostic biomarkers for disease management and for assessing treatment efficacies.
开发和测试一种非接触、无对比的视网膜激光散斑对比成像（LSCI）仪器，用于小型啮齿动物，以评估血管解剖结构、量化血液动力学，并测量对视网膜血管功能障碍的广泛视野（FOV）的生理变化。
构建了一种能够在小型啮齿动物中进行大视野和非接触成像的定制 LSCI 仪器。在确定 LSCI 测量的重复性之前，标准化了相机增益、激光功率和曝光时间对散斑对比度变化的影响。最后，分别使用激光诱导的分支视网膜静脉阻塞和异氟烷麻醉模型评估 LSCI 检测局部和全身血管功能变化的能力。
LSCI 系统生成对比度为零的视网膜血流图，FOV 为 50°，帧率超过 376 帧/秒（fps），曝光时间短（>50 μs），可靠性高（组内相关系数 R = 0.946）。LSCI 用于描述受激光损伤影响的视网膜血管解剖结构，并纵向测量灌注和血流轮廓的变化。在不同剂量的异氟烷下，LSCI 可以评估心脏和全身血管功能，包括心率、外周阻力、收缩性和脉搏传播。
我们提出了一种 LSCI 系统，用于检测小型啮齿动物视网膜和全身血管健康和功能的解剖和生理变化。
彭鹏
