Guran T, Zeimer R C, Shahidi M, Mori M T
Department of Ophthalmology, University of Illinois, College of Medicine, Chicago.
Invest Ophthalmol Vis Sci. 1990 Nov;31(11):2300-6.
A new method designed to allow repeated mapping of retinal hemodynamics on a macro- and microcirculatory level was evaluated in the primate eye. The method, called "targeted dye delivery," consists of encapsulating a fluorescent dye in temperature-sensitive liposomes, injecting the liposomes systemically, and using a light pulse from an argon laser to release a bolus of dye in a targeted retinal vessel. The follow-up of the well-defined dye front thus generated allows calculation of the blood flow and capillary transit time. Evaluation of targeted dye delivery in a monkey indicated that centerline blood velocity and the vessel diameter can be measured with a reproducibility of 10% and 4%, respectively, in vessels that are 40 microns and larger. These measurements yielded flow values that had a reproducibility of 10% on the same day and 13% on different days. The normalization of flow rate by the vessel diameter was consistent with theoretic estimates and promises to be a circulation indicator independent of variations between individual and species. The transit time across capillary beds at different locations was found to be similar, thus indicating that the method could be used to evaluate the local viability of the microcirculation.
一种旨在允许在灵长类动物眼睛的宏观和微循环水平上对视网膜血流动力学进行重复映射的新方法得到了评估。这种方法称为“靶向染料递送”，包括将荧光染料包裹在热敏脂质体中，全身注射脂质体，然后使用氩激光的光脉冲在靶向视网膜血管中释放一团染料。对由此产生的明确染料前沿的跟踪允许计算血流量和毛细血管通过时间。在一只猴子身上对靶向染料递送的评估表明，在40微米及以上的血管中，中心线血流速度和血管直径的测量重复性分别为10%和4%。这些测量得出的流量值在同一天的重复性为10%，在不同天的重复性为13%。通过血管直径对流速进行归一化与理论估计一致，并有望成为一个独立于个体和物种差异的循环指标。发现在不同位置穿过毛细血管床的通过时间相似，因此表明该方法可用于评估微循环的局部活力。
