Photothermal-therapy (PTT) inculcates near-infrared laser guided local heating effect, where high degree of precision is expected, but not well proven to-date. An ex vivo tissue biochemical map with molecular/biochemical response showing the coverage area out of an optimized PTT procedure can reveal precision information. In this work, Raman-microscopic mapping and linear discriminant analysis of spectra of PTT treated and surrounding tissue areas ex vivo are done, revealing three distinct spectral clusters/zones, with minimal overlap between the core treated and adjacent untreated zone. The core treated zone showed intense nucleic-acid, cytochrome/mitochondria and protein damage, an adjacent zone showed lesser degree of damages and far zone showed minimal/no damage. Immunohistochemistry for γH2AX (DNA damage marker protein) in PTT exposed tissue also revealed similar results. Altogether, this study reveals the utility of Raman-microspectroscopy for fine-tuning safety parameters and precision that can be achieved from PTT mediated tumor ablation in preclinical/clinical application.

光热疗法 (PTT) 灌输了近红外激光引导的局部加热效应，预计精度很高，但迄今为止尚未得到很好的证明。具有分子/生化反应的离体组织生化图显示优化的 PTT 程序的覆盖区域可以揭示精确信息。在这项工作中，离体PTT 处理和周围组织区域的光谱的拉曼显微映射和线性判别分析完成后，揭示了三个不同的光谱簇/区域，核心处理区域和相邻未处理区域之间的重叠最小。核心处理区表现出强烈的核酸、细胞色素/线粒体和蛋白质损伤，邻近区表现出较小程度的损伤，远区表现出最小/无损伤。PTT 暴露组织中 γH2AX（DNA 损伤标记蛋白）的免疫组织化学也显示了类似的结果。总而言之，这项研究揭示了拉曼显微光谱在临床前/临床应用中可通过 PTT 介导的肿瘤消融实现微调安全参数和精度的效用。