Monitoring of tissue coagulation during thermotherapy using optoacoustic technique
Monitoring of tissue coagulation during thermotherapy using optoacoustic technique
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DOI：
10.1088/0022-3727/38/15/017
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发表时间：
2005-08-07
影响因子：
3.4
通讯作者：
Esenaliev, RO
中科院分区：
文献类型：
--
作者：
Larin, KV;Larina, IV;Esenaliev, RO
在本文中，我们应用激光光声技术对组织中的热损伤进行实时无创监测。通过测量和分析光声信号的幅度和时间特性来检测凝固过程中组织光学特性的变化。通过样品的间质连续波 Nd:YAG 激光照射或通过传导加热来诱导肝脏、心肌和前列腺的凝固。使用灵敏的宽带声换能器实时检测热引起的光学特性变化。应用光声和漫反射技术相结合来测定组织光学特性：有效衰减、总漫反射、减少散射系数和吸收系数。光学特性在达到凝固温度（约 53 摄氏度）时没有变化，并且在加热到 70 摄氏度时急剧增加。以约 0.6 毫米的空间分辨率实时监测新鲜切除的犬组织内间质凝固前沿的扩张。我们的研究结果表明，该技术有可能用于厘米级深度的恶性和良性病变的实时精确热疗。
In this paper we have applied the laser optoacoustic technique for real time noninvasive monitoring of thermal damage in tissues. Changes in tissue optical properties during coagulation were detected by measuring and analysing amplitude and temporal characteristics of optoacoustic signals. Coagulation of liver, myocardium and prostate was induced by interstitial continuous wave Nd: YAG laser irradiation of the samples or by conductive heating. Real time detection of thermally-induced changes in optical properties was performed with sensitive wide-band acoustic transducers. Combination of optoacoustic and diffuse reflectance technique was applied for determination of tissue optical properties: effective attenuation, total diffuse reflectance, reduced scattering coefficient and absorption coefficient. The optical properties did not change up to temperature of coagulation (about 53 degrees C) and sharply increased during heating up to 70 degrees C. Monitoring of the expansion of interstitial coagulation front within freshly excised canine tissues was performed in real time with spatial resolution of about 0.6 mm. The results of our study suggest that this technique can potentially be used for real time precise thermotherapy of malignant and benign lesions at depths of the order of the centimetre.