Cheung Anthony T W, Chen Peter C Y, Larkin Edward C, Duong Patricia L, Ramanujam Sahana, Tablin Fern, Wun Ted
Department of Medical Pathology, University of California (UC) Davis School of Medicine, Davis, CA 95817, USA.
Blood. 2002 Jun 1;99(11):3999-4005. doi: 10.1182/blood.v99.11.3999.
The conjunctival microcirculation of 18 homozygous sickle cell disease (SCD) patients during steady-state, painful crisis, and postcrisis conditions was recorded on high-resolution videotapes using intravital microscopy. Selected videotape sequences were subsequently coded, frame-captured, studied, and blindly analyzed using computer-assisted image analysis protocols. At steady-state (baseline), all SCD patients exhibited some of the following morphometric abnormalities: abnormal vessel diameter, comma signs, blood sludging, boxcar blood flow phenomenon, distended vessels, damaged vessels, hemosiderin deposits, vessel tortuosity, and microaneurysms. There was a decrease in vascularity (diminished presence of conjunctival vessels) in SCD patients compared with non-SCD controls, giving the bulbar conjunctiva a "blanched" avascular appearance in most but not all SCD patients during steady-state. Averaged steady-state red cell velocity in SCD patients was slower than in non-SCD controls. During painful crisis, a further decrease in vascularity (caused by flow stoppage in small vessels) and a 36.7% +/- 5.2% decrease in large vessel (mostly venular) diameter resulted. In addition, the conjunctival red cell velocities either slowed significantly (6.6% +/- 13.1%; P <.01) or were reduced to a trickle (unmeasurable) during crisis. The microvascular changes observed during crisis were transient and reverted to steady-state baseline after resolution of crisis. When combined, intravital microscopy and computer-assisted image analysis (computer-assisted intravital microscopy) represent the availability of a noninvasive tool to quantify microvascular abnormalities in vascular diseases, including sickle cell disease. The ability to identify and relocate the same conjunctival vessels for longitudinal studies uniquely underscores the applicability of this quantitative real-time technology.
使用活体显微镜，在高分辨率录像带上记录了18例纯合子镰状细胞病（SCD）患者在稳态、疼痛危象和危象后状态下的结膜微循环情况。随后，对选定的录像带序列进行编码、逐帧捕捉、研究，并使用计算机辅助图像分析协议进行盲法分析。在稳态（基线）时，所有SCD患者均表现出以下一些形态学异常：血管直径异常、逗号征、血液淤积、车厢状血流现象、血管扩张、血管损伤、含铁血黄素沉积、血管迂曲和微动脉瘤。与非SCD对照组相比，SCD患者的血管密度降低（结膜血管数量减少），在稳态时，大多数（但并非所有）SCD患者的球结膜呈现“苍白”的无血管外观。SCD患者的平均稳态红细胞速度比非SCD对照组慢。在疼痛危象期间，血管密度进一步降低（由小血管血流停滞引起），大血管（主要是静脉）直径下降36.7%±5.2%。此外，在危象期间，结膜红细胞速度要么显著减慢（6.6%±13.1%；P<.01），要么降至涓流（无法测量）。危象期间观察到的微血管变化是短暂的，危象缓解后恢复到稳态基线。活体显微镜检查和计算机辅助图像分析（计算机辅助活体显微镜检查）相结合，代表了一种可用于量化包括镰状细胞病在内的血管疾病中微血管异常的非侵入性工具。能够识别并重新定位同一结膜血管以进行纵向研究，这独特地强调了这种定量实时技术的适用性。
