Department of Physics, Politecnico di Milano, Milan, Italy.
Multi-Modality Medical Imaging Group, University of Twente, Enschede, The Netherlands.
Sci Rep. 2021 Mar 22;11(1):6579. doi: 10.1038/s41598-021-85653-0.
Accurate monitoring of treatment is crucial in minimally-invasive radiofrequency ablation in oncology and cardiovascular disease. We investigated alterations in optical properties of ex-vivo bovine tissues of the liver, heart, muscle, and brain, undergoing the treatment. Time-domain diffuse optical spectroscopy was used, which enabled us to disentangle and quantify absorption and reduced scattering spectra. In addition to the well-known global (1) decrease in absorption, and (2) increase in reduced scattering, we uncovered new features based on sensitive detection of spectral changes. These absorption spectrum features are: (3) emergence of a peak around 840 nm, (4) redshift of the 760 nm deoxyhemoglobin peak, and (5) blueshift of the 970 nm water peak. Treatment temperatures above 100 °C led to (6) increased absorption at shorter wavelengths, and (7) further decrease in reduced scattering. This optical behavior provides new insights into tissue response to thermal treatment and sets the stage for optical monitoring of radiofrequency ablation.
准确监测治疗在肿瘤学和心血管疾病的微创射频消融中至关重要。我们研究了在治疗过程中，离体牛肝、心脏、肌肉和脑组织的光学特性的变化。我们使用了时域漫反射光学光谱技术，该技术使我们能够分辨和量化吸收和散射光谱。除了众所周知的（1）吸收整体下降和（2）散射增加之外，我们还根据对光谱变化的敏感检测，发现了新的特征。这些吸收光谱特征包括：（3）在 840nm 左右出现峰值，（4）760nm 去氧血红蛋白峰值红移，以及（5）970nm 水峰蓝移。治疗温度高于 100°C 会导致（6）较短波长处吸收增加，以及（7）散射进一步减少。这种光学行为为组织对热治疗的反应提供了新的见解，并为射频消融的光学监测奠定了基础。
