Ma Dinglong, Bec Julien, Yankelevich Diego R, Gorpas Dimitris, Fatakdawala Hussain, Marcu Laura
University of California, Department of Biomedical Engineering, 451 Health Sciences Drive, Davis, California 95616.
University of California, Department of Biomedical Engineering, 451 Health Sciences Drive, Davis, California 95616bUniversity of California, Department of Electrical Engineering, 3101 Kemper Hall, Davis, California 95616.
J Biomed Opt. 2014 Jun;19(6):066004. doi: 10.1117/1.JBO.19.6.066004.
We report the development and validation of a hybrid intravascular diagnostic system combining multispectral fluorescence lifetime imaging (FLIm) and intravascular ultrasound (IVUS) for cardiovascular imaging applications. A prototype FLIm system based on fluorescence pulse sampling technique providing information on artery biochemical composition was integrated with a commercial IVUS system providing information on artery morphology. A customized 3-Fr bimodal catheter combining a rotational side-view fiberoptic and a 40-MHz IVUS transducer was constructed for sequential helical scanning (rotation and pullback) of tubular structures. Validation of this bimodal approach was conducted in pig heart coronary arteries. Spatial resolution, fluorescence detection efficiency, pulse broadening effect, and lifetime measurement variability of the FLIm system were systematically evaluated. Current results show that this system is capable of temporarily resolving the fluorescence emission simultaneously in multiple spectral channels in a single pullback sequence. Accurate measurements of fluorescence decay characteristics from arterial segments can be obtained rapidly (e.g., 20 mm in 5 s), and accurate co-registration of fluorescence and ultrasound features can be achieved. The current finding demonstrates the compatibility of FLIm instrumentation with in vivo clinical investigations and its potential to complement conventional IVUS during catheterization procedures.
我们报告了一种用于心血管成像应用的混合血管内诊断系统的开发与验证，该系统结合了多光谱荧光寿命成像（FLIm）和血管内超声（IVUS）。基于荧光脉冲采样技术的FLIm原型系统可提供动脉生化成分信息，它与提供动脉形态信息的商用IVUS系统集成在一起。构建了一种定制的3-Fr双峰导管，该导管结合了旋转侧视光纤和40-MHz IVUS换能器，用于对管状结构进行连续螺旋扫描（旋转和回撤）。在猪心脏冠状动脉中对这种双峰方法进行了验证。系统评估了FLIm系统的空间分辨率、荧光检测效率、脉冲展宽效应和寿命测量变异性。目前的结果表明，该系统能够在单次回撤序列中同时在多个光谱通道中临时分辨荧光发射。可以快速获得动脉段荧光衰减特性的准确测量结果（例如，5秒内测量20毫米），并且可以实现荧光和超声特征的精确配准。当前的研究结果证明了FLIm仪器与体内临床研究具有兼容性，并且在导管插入手术过程中具有补充传统IVUS的潜力。
