Leon M B, Lu D Y, Prevosti L G, Macy W W, Smith P D, Granovsky M, Bonner R F, Balaban R S
Cardiology Branch, National Heart, Lung, and Blood Institute, Bethesda, Maryland 20892.
J Am Coll Cardiol. 1988 Jul;12(1):94-102. doi: 10.1016/0735-1097(88)90361-0.
In vivo plaque recognition may be important for safe and precise intra-arterial atheroma ablation during laser coronary angioplasty. This study examined the feasibility and sensitivity of utilizing quantitative fluorescence spectroscopy and video-enhanced fluorescence imaging for plaque identification in atherosclerotic human necropsy arterial wall before and after laser atheroma ablation. With wide-band (450 to 490 nm) blue light excitation, the 540 nm fluorescence intensity ratio of normal to diseased sites (n = 13) was 2.09 +/- 0.82 (p less than 0.001) and video fluorescence imaging provided enhanced delineation of atheroma surface characteristics. Continuous argon and pulsed excimer (308 nm) laser ablation of atheroma decreased fluorescence intensity ratios by 42 and 20% (p less than 0.001), respectively (that is, from abnormal to nearly normal). Low power 325 nm laser-excited fluorescence spectroscopy from normal (n = 115) and abnormal (n = 146) necropsy sites revealed an average 45% decrease in atheroma fluorescence intensity (p less than 0.0001) and changes in fluorescence spectra appearance that corresponded to plaque morphologic subtypes. Studies using a dual laser system combining 325 nm laser-excited fluorescence plaque recognition and a 480 nm pulsed dye laser for tissue ablation with common optical fibers demonstrated normalization of both fluorescence intensity and spectra appearance after laser atheroma ablation. Thus, in vitro analysis of surface arterial fluorescence by quantitative spectroscopy and video fluorescence imaging reliably differentiate plaque from normal tissue and may provide the feedback signal needed to activate a laser source for selective plaque removal.
在激光冠状动脉成形术期间，体内斑块识别对于安全、精确地进行动脉粥样硬化斑块消融可能很重要。本研究检测了在激光斑块消融前后，利用定量荧光光谱法和视频增强荧光成像技术识别动脉粥样硬化人体尸检动脉壁中斑块的可行性和敏感性。在宽带（450至490纳米）蓝光激发下，正常部位与病变部位（n = 13）的540纳米荧光强度比为2.09±0.82（p<0.001），视频荧光成像增强了对动脉粥样硬化斑块表面特征的描绘。连续氩激光和脉冲准分子（308纳米）激光对动脉粥样硬化斑块的消融分别使荧光强度比降低了42%和20%（p<0.001）（即从异常变为接近正常）。对正常（n = 115）和异常（n = 146）尸检部位进行低功率325纳米激光激发荧光光谱分析，结果显示动脉粥样硬化斑块的荧光强度平均降低了45%（p<0.0001），且荧光光谱外观的变化与斑块形态学亚型相对应。使用双激光系统（将325纳米激光激发荧光斑块识别与480纳米脉冲染料激光通过共用光纤进行组织消融相结合）的研究表明，激光斑块消融后荧光强度和光谱外观均恢复正常。因此，通过定量光谱法和视频荧光成像对动脉表面荧光进行体外分析，能够可靠地将斑块与正常组织区分开来，并可能提供激活激光源以选择性去除斑块所需的反馈信号。
