Nadkarni Seemantini K, Bouma Brett E, Yelin Dvir, Gulati Amneet, Tearney Guillermo J
Harvard Medical Schooland Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts 02114, USA.
J Biomed Opt. 2008 Sep-Oct;13(5):054016. doi: 10.1117/1.2982529.
Laser speckle imaging (LSI), a new technique that measures an index of plaque viscoelasticity, has been investigated recently to characterize atherosclerotic plaques. These prior studies demonstrated the diagnostic potential of LSI for detecting high-risk plaques and were conducted ex vivo. To conduct intracoronary LSI in vivo, the laser speckle pattern must be transmitted from the coronary wall to the image detector in the presence of cardiac motion. Small-diameter, flexible optical fiber bundles, similar to those used in coronary angioscopy, may be incorporated into an intravascular catheter for this purpose. A key challenge is that laser speckle is influenced by inter-fiber leakage of light, which may be exacerbated during bundle motion. In this study, we tested the capability of optical fiber bundles to transmit laser speckle patterns obtained from atherosclerotic plaques and evaluated the influence of motion on the diagnostic accuracy of fiber bundle-based LSI. Time-varying helium-neon laser speckle images of aortic plaques were obtained while cyclically moving the flexible length of the bundle to mimic coronary motion. Our results show that leached fiber bundles may reliably transmit laser speckle images in the presence of cardiac motion, providing a viable option to conduct intracoronary LSI.
激光散斑成像（LSI）是一种测量斑块粘弹性指标的新技术，最近已被用于研究动脉粥样硬化斑块的特征。这些先前的研究证明了LSI在检测高危斑块方面的诊断潜力，并且是在体外进行的。为了在体内进行冠状动脉LSI，在心脏运动的情况下，激光散斑图案必须从冠状动脉壁传输到图像探测器。为此，类似于冠状动脉血管镜检查中使用的小直径柔性光纤束可被纳入血管内导管。一个关键挑战是激光散斑受光纤间光泄漏的影响，在束运动期间这种影响可能会加剧。在本研究中，我们测试了光纤束传输从动脉粥样硬化斑块获得的激光散斑图案的能力，并评估了运动对基于光纤束的LSI诊断准确性的影响。在循环移动束的柔性部分以模拟冠状动脉运动的同时，获取了主动脉斑块的随时间变化的氦氖激光散斑图像。我们的结果表明，在心脏运动的情况下，浸出光纤束可以可靠地传输激光散斑图像，为进行冠状动脉LSI提供了一个可行的选择。
