DETECTION OF VULNERABLE PLAQUES USING RAMAN, FLUORESCENCE AND REFLECTANCE SPECT

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得主要资金， 因此可以在其他CRISP条目中表示。列出的机构是 中心，不一定是研究者的机构。 易损斑块的特征在于形态学特征，例如薄的或溃疡的纤维帽、大的坏死核心、表面泡沫细胞和斑块内出血。我们主张使用多模式光谱方法，包括拉曼，漫反射，和固有荧光光谱，检测这些关键的形态标志物的易损斑块。对17例人颈动脉标本进行了体外初步研究。采集光谱后，对每个标本进行组织学评价。它被确定，从漫反射光谱，血红蛋白浓度和散射参数，获得的参数，可以潜在地用于检测斑块内出血和泡沫细胞，分别。从内在荧光中提取的与组织最顶层中胶原蛋白的量相关的参数可用于感测薄纤维帽的存在。最后，与胆固醇和坏死物质的量相关的拉曼光谱参数可以潜在地用于检测坏死核心。多峰光谱方法显示出很大的希望，提供深度敏感和互补的形态信息的斑块组成。需要更大规模的研究来进一步验证易损斑块诊断的潜力，这将是我们未来工作的重点。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Vulnerable plaques are characterized by morphological features such as a thin or ulcerated fibrous cap, a large necrotic core, superficial foam cells, and intraplaque hemorrhage. We argue for the use of a multimodal spectroscopic method, comprising Raman, diffuse reflectance, and intrinsic fluorescence spectroscopy, to detect these key morphological markers of vulnerable plaque. A preliminary study was performed in vitro on 17 human carotid artery specimens. Following the acquisition of the spectra, each specimen was histologically evaluated. It was determined that parameters obtained from diffuse reflectance spectroscopy, the hemoglobin concentration and the scattering parameter, can potentially be used to detect intraplaque hemorrhage and foam cells, respectively. A parameter extracted from the intrinsic fluorescence that relates to the amount of collagen in the topmost layers of the tissue can be used to sense the presence of a thin fibrous cap. Finally, a Raman spectroscopy parameter related to the amount of cholesterol and necrotic material can potentially be used to detect a necrotic core. The multimodal spectroscopy method shows great promise to provide depth-sensitive and complementary morphological information about plaque composition. A larger study is needed to further validate the potential for diagnosis of vulnerable plaque and this shall be the focus of our future work.