Flower R W, Fryczkowski A W, McLeod D S
Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723-6099, USA.
Invest Ophthalmol Vis Sci. 1995 Jun;36(7):1247-58.
To investigate variability of choriocapillaris blood flow patterns.
After the intravenous injection of indocyanine green, angiograms were recorded at 30 images per second in rhesus monkey eyes using a fundus camera equipped with a pulsed laser diode light source, synchronized with a gated (5 msec), intensified charge-coupled device, or CCD, video camera. Images of choriocapillaris filling alone were extracted. Plastic corrosion casts were made of two of the monkey's choroidal vasculatures for subsequent scanning electron microscopy examination.
Pulsed laser indocyanine green fluorescence excitation produced better definition of choriocapillaris filling than had been achieved using continuous illumination. No correlation was found between the choriocapillaris plexus architecture revealed by the plastic corrosion casts and the observed choriocapillaris lobular filling. Overall posterior pole choriocapillaris dye-filling patterns were relatively stable for periods of days, but they changed gradually for periods of weeks. Localized minor pattern changes occurred on a much shorter time scale. Choriocapillaris filling patterns were altered by acutely elevating intraocular pressure, by O2 and CO2 breathing, and by argon laser retinal photocoagulation of adjacent areas.
Choriocapillaris filling patterns appear to be determined by the network of perfusion pressure gradients that exist among the interspersed feeding arterioles and draining venules connected to the choriocapillaris plexus. Changes in intraocular pressure and in blood PO2 and PCO2 levels can produce marked changes in the distribution of choriocapillaris blood flow. Retinal laser photocoagulation of adjacent fundus areas alters choriocapillaris blood flow to the extent that the altered flow might be an important factor in the beneficial results attributed to retinal laser treatment.
研究脉络膜毛细血管血流模式的变异性。
静脉注射吲哚菁绿后，使用配备脉冲激光二极管光源的眼底相机，以每秒30帧的速度记录恒河猴眼睛的血管造影图像，该相机与门控（5毫秒）、增强型电荷耦合器件（CCD）摄像机同步。提取仅脉络膜毛细血管充盈的图像。对两只猴子的脉络膜血管系统制作塑料腐蚀铸型，用于后续扫描电子显微镜检查。
脉冲激光吲哚菁绿荧光激发比连续照明能更清晰地显示脉络膜毛细血管充盈。塑料腐蚀铸型显示的脉络膜毛细血管丛结构与观察到的脉络膜毛细血管小叶充盈之间未发现相关性。整个后极部脉络膜毛细血管染料充盈模式在数天内相对稳定，但在数周内会逐渐变化。局部微小模式变化发生的时间尺度要短得多。急性眼压升高、吸氧和二氧化碳、以及对相邻区域进行氩激光视网膜光凝都会改变脉络膜毛细血管充盈模式。
脉络膜毛细血管充盈模式似乎由与脉络膜毛细血管丛相连的散在供血小动脉和引流小静脉之间存在的灌注压力梯度网络所决定。眼压、血液中氧分压和二氧化碳分压水平的变化可导致脉络膜毛细血管血流分布发生显著变化。对相邻眼底区域进行视网膜激光光凝会改变脉络膜毛细血管血流，这种改变的血流可能是视网膜激光治疗产生有益效果的一个重要因素。
