基于特殊材料的多参量高分辨光声显微成像技术研究

光声成像，以其结合了光学成像的高对比度特性与超声成像的深层探测能力，正迅速成为一个新兴的成像领域。该技术利用红细胞中的血红蛋白作为内源性对比剂，能够清晰地描绘生物微血管的结构细节。通过分析不同生物组织对光的吸收特性，光声成像能够提供血氧饱和度等关键生理信息的多维成像。此外，通过引入高度特异性的外源性对比剂，光声成像在分子层面的灵敏度得以显著提升，有效地解决了内源性标记在疾病标定与诊断上的局限性。

现有的光声成像方法很少能够同时将结构、功能和分子影像紧密结合 。针对这一现状，本课题将着手于多参量高分辨光声显微成像方法的研究，以期获得完整的血管结构、功能及光声分子信息，扩展其应用领域。

此外，在实际活体成像过程中，皮肤、颅骨等组织对光的散射与吸收，以及被测体的体温与呼吸抖动往往对成像质量有极大的影响，因此，探索新的成像窗口，设计合适的成像固定夹具与加热装置，有助于避开皮肤与颅骨的影响，降低被测体成像过程中的抖动，维持活体成像时的生命体征。

从上述背景出发，本文利用双光源结合受激拉曼散射的方案，设计和搭建了三波长多参量高分辨光声显微成像系统，内容包括光路、成像探头、数据采集与系统控制部分以及相关图像处理算法的设计与实现，并通过仿体与活体实验验证了系统成像性能的可靠性。在光路的材料选择上，通过对不同种拉曼光纤材料学参数的研究与测试，选择最高激发效率的拉曼光纤。在成像系统的应用层面，探索出高度贴合光声成像需求的窗口材料，并设计制作轻质、稳固、可连续监测的成像固定夹具。同时，选取性能优越3D打印材料，设计出适合本系统的成像加热装置。最后，基于皮下转移瘤和同种原位移植脑胶质瘤两种疾病模型，结合光声分子探针，对系统连续活体监测能力进行了验证。三波长多参量高分辨光声显微成像技术在生物结构、分子和功能成像研究中提供了重要的成像技术手段，对肿瘤等疾病的发病机理研究及其预后提供了新的思路。

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