FLUORESCENCE-GUIDED LASER ANGIOPLASTY USING MULTIFIBER LASER CATHETERS

以前，我们已经开发了一种荧光引导血管成形术系统， 利用荧光光谱法引导脉冲染料激光器， 选择性动脉粥样硬化切除术。然而，该装置在临床上受到限制， 因为输送系统包括单个小直径 激光纤维导丝导致主通道再通，但 需要随后的球囊血管成形术来进行最终的管腔扩张， 所有案件。因此，有必要开发一个更大的 基于导管的系统，可提供明确的动脉粥样硬化清除， 狭窄或闭塞冠状动脉的大表面积再通， 外周血管同心和偏心多纤维设计导管 对用于导丝放置的工作通腔进行了测试，以评估 荧光光谱传感和组织消融参数。这些 用于冠状动脉的导管为4.5 Fr，用于外周血管的导管为6.5 Fr 动脉使用。可跟踪性和灵活性与体内轻松兼容 经导管应用。经过广泛的体外测试，利用人类 动脉粥样硬化物质，我们得出结论， 荧光传感激光导管仍然提供可靠的组织 通过480 nM脉冲染料识别并准确引导斑块消融 激光器研究的参数包括计算机算法的变化， 异质位点的复合传感，光漂白现象， 与热组织效应相关的荧光变化，以及 要求从多个小坑中引出均匀的大面积坑 纤维这些基本评价推动了若干 设计变更，我们预计将导致导管设计工作， 临床研究在不久的将来。

Previously, we had developed a fluorescence-guided angioplasty system utilizing fluorescence spectroscopy to direct a pulse dye laser for selective atheroma removal. However, this device was limited in clinical application because the delivery system comprised a single small diameter laser fiber wire which resulted in primary channel recanalization but required subsequent balloon angioplasty for definitive luminal expansion in all cases. Therefore, it became necessary to develop a larger catheter-based system which would provide definitive atheroma removal with large surface area recanalization of stenotic or occluded coronary and peripheral vessels. Concentric and eccentric multifiber design catheters with a working through lumen for guide-wire placement were tested to asses fluorescence spectroscopic sensing and tissue ablation parameters. These catheters were 4.5 French for coronary use and 6.5 French for peripheral artery use. Trackability and flexibility were compatible with easy in vivo transcatheter application. After extensive in vitro testing utilizing human ecropsy atherosclerotic material, we concluded that a multifiber fluorescence-sensing laser catheter still provides reliable tissue recognition and accurately guides plaque ablation by a 480 nM pulse dye laser. Parameter studied included changes in computer algorithms for composite sensing of heterogeneous sites, photobleaching phenomena, florescence changes associated with thermal tissue effects, and requirements to elicit a homogeneous large area crater from multiple small fibers. These basic evaluations have provided the impetus for several design changes which we expect will result in a working catheter design for clinical studies in the near future.