Zeimer R C, Guran T, Shahidi M, Mori M T
Department of Ophthalmology, University of Illinois, Chicago College of Medicine.
Invest Ophthalmol Vis Sci. 1990 Aug;31(8):1459-65.
Although fluorescein angiography has proven to be an important tool in the diagnosis and management of retinal vascular diseases, it is subject to certain limitations, namely the presence of the choroidal background, which usually precludes a detailed examination of the retinal microvasculature. Moreover, the inability to repeat the bolus reduces the chance of obtaining high-quality photographs of early phases, and does not allow for a complete binocular examination or for testing the response to induced physiologic changes. We have developed a method of targeted dye delivery that consists of encapsulating the dye in lipid vesicles, injecting them intravenously, and causing them to release their contents locally when a short heat pulse is induced in a retinal artery by a laser. This method was applied in the rhesus monkey in order to visualize the retinal microvasculature. A well-defined bolus and absence of background fluorescence permitted both following of the dye front through the vasculature and clear imaging of the capillary network over the whole posterior pole. The bolus delivery could be repeated as many as 100 times in 45 min without significant loss of contrast. The comparison of these results with conventional fluorescein angiography illustrated the advantage of the new method. The examination of the safety of the delivery system indicates that there is no major obstacle to the eventual application to humans.
尽管荧光素血管造影已被证明是诊断和治疗视网膜血管疾病的重要工具，但它存在一定的局限性，即脉络膜背景的存在，这通常会妨碍对视网膜微血管系统进行详细检查。此外，无法重复注射团注减少了获得早期高质量照片的机会，并且不允许进行完整的双眼检查或测试对诱导生理变化的反应。我们开发了一种靶向染料递送方法，该方法包括将染料包裹在脂质囊泡中，静脉注射，然后当通过激光在视网膜动脉中诱导短热脉冲时，使它们在局部释放其内容物。该方法应用于恒河猴以可视化视网膜微血管系统。明确的团注和无背景荧光使得既能跟踪染料前沿通过血管系统，又能清晰成像整个后极的毛细血管网络。在45分钟内可以重复进行多达100次团注递送，而对比度没有明显损失。将这些结果与传统荧光素血管造影进行比较说明了新方法的优势。对递送系统安全性的检查表明，最终应用于人类没有重大障碍。
