Chang A A, Morse L S, Handa J T, Morales R B, Tucker R, Hjelmeland L, Yannuzzi L A
Department of Ophthalmology, University of California, Davis, Sacramento, California 95816, USA.
Ophthalmology. 1998 Jun;105(6):1060-8. doi: 10.1016/S0161-6420(98)96008-0.
This study aimed to histologically localize indocyanine green (ICG) dye in the geriatric primate and human eye and to correlate these findings with clinical ICG angiography.
The study design was a clinicopathologic correlation.
Six eyes of three geriatric monkeys (Maccaca mulatta) with macular drusen, 19 to 29 years of age, housed at the California Primate Research Center and an enucleated human eye from a 66-year-old patient with choroidal melanoma were examined.
All six monkey eyes and the human eye underwent clinical ICG angiography. Five monkey eyes were enucleated at varying intervals after intravenous ICG dye injection for histologic examination. One monkey eye was removed without prior ICG injection as an age-matched control. The human eye was enucleated after intravenous injection of ICG dye.
Infrared fluorescence microscopy of freeze-dried tissue sections was performed to detect ICG fluorescence. Histologic sections were stimulated with an 810-nm diode laser, and the fluorescence emitted was detected with a Hamamatsu infrared camera. The images were digitally recorded. The distribution of fluorescence on histologic examination was correlated with the fluorescence of the clinical ICG angiogram.
Infrared fluorescence microscopy of monkey sections localized fluorescence within retinal and choroidal vessels early after injection of ICG dye. The ICG fluorescence was seen in the extravascular choroidal stroma within 10 minutes after injection. The stromal fluorescence persisted in sections obtained 50 minutes after injection of ICG. The retinal pigment epithelium (RPE)-Bruch's membrane complex was brightly fluorescent in the middle- and late-stage histologic sections. Drusen deposits were brightly fluorescent at all timepoints examined. Similar findings were observed in freeze-dried tissue sections of the human eye. The fluorescence detected on histologic sections correlated closely with the fluorescence of the clinical ICG angiograms for the same interval.
The ICG dye does not remain solely within the choroidal intravascular space but extravasates into the choroidal stroma and accumulates within the RPE. Extravascular ICG binds to drusen material. These findings will enhance the interpretation of clinical ICG angiography.
本研究旨在从组织学角度确定老年灵长类动物和人眼中吲哚菁绿（ICG）染料的位置，并将这些发现与临床ICG血管造影结果相关联。
本研究设计为临床病理相关性研究。
对加利福尼亚灵长类动物研究中心饲养的3只年龄在19至29岁、患有黄斑玻璃膜疣的老年猕猴的6只眼睛，以及一只来自一名66岁脉络膜黑色素瘤患者的摘除眼球进行了检查。
所有6只猴眼和人眼均接受了临床ICG血管造影。在静脉注射ICG染料后的不同时间间隔，摘除5只猴眼用于组织学检查。未预先注射ICG而摘除1只猴眼作为年龄匹配的对照。人眼在静脉注射ICG染料后被摘除。
对冻干组织切片进行红外荧光显微镜检查以检测ICG荧光。组织切片用810纳米二极管激光激发，并用滨松红外相机检测发出的荧光。图像进行数字记录。组织学检查中荧光的分布与临床ICG血管造影的荧光相关联。
猴眼切片的红外荧光显微镜检查显示，在注射ICG染料后早期，视网膜和脉络膜血管内出现荧光。注射后10分钟内，在血管外脉络膜基质中可见ICG荧光。在注射ICG后50分钟获得的切片中，基质荧光持续存在。在组织学检查的中晚期切片中，视网膜色素上皮（RPE）-布鲁赫膜复合体发出明亮荧光。在所有检查时间点，玻璃膜疣沉积物均发出明亮荧光。在人眼的冻干组织切片中也观察到类似结果。组织学切片上检测到的荧光与同一时间间隔的临床ICG血管造影荧光密切相关。
ICG染料并非仅停留在脉络膜血管内，而是渗出到脉络膜基质中并积聚在RPE内。血管外ICG与玻璃膜疣物质结合。这些发现将有助于临床ICG血管造影的解读。
