Li Zhifang, Chen Haiyu, Zhou Feifan, Li Hui, Chen Wei R
Fujian Provincial Key Laboratory of Photonic Technology, Key Laboratory of Optoelectronic Science and Technology for Medicine, Ministry of Education, College of Photonic and Electronic Engineering, Fujian Normal University, Fuzhou 350007, China.
Department of Cardiovascular Surgery, Fujian Provincial Hospital, Fujian Medical University, Fuzhou 350000, China.
Sensors (Basel). 2015 Mar 6;15(3):5583-93. doi: 10.3390/s150305583.
Photothermal therapy is an effective means to induce tumor cell death, since tumor tissue is more sensitive to temperature increases than normal tissue. Biological responses depend on tissue temperature; target tissue temperature needs to be precisely measured and controlled to achieve desired thermal effects. In this work, a unique photoacoustic (PA) sensor is proposed for temperature measurement during interstitial laser phototherapy. A continuous-wave laser light and a pulsed laser light, for photothermal irradiation and photoacoustic temperature measurement, respectively, were delivered to the target tissue through a fiber coupler. During laser irradiation, the PA amplitude was measured. The Grüneisen parameter and the bioheat equation were used to determine the temperature in strategic positions in the target tissue. Our results demonstrate that the interstitial PA amplitude is a linear function of temperature in the range of 22 to 55 °C, as confirmed by thermocouple measurement. Furthermore, by choosing appropriate laser parameters, the maximum temperature surrounding the active diffuse fiber tip in tissue can be controlled in the range of 41 to 55 °C. Thus, this sensor could potentially be used for fast, accurate, and convenient three-dimensional temperature measurement, and for real-time feedback and control of interstitial laser phototherapy in cancer treatment.
光热疗法是诱导肿瘤细胞死亡的有效手段，因为肿瘤组织比正常组织对温度升高更敏感。生物反应取决于组织温度；需要精确测量和控制目标组织温度以实现所需的热效应。在这项工作中，提出了一种独特的光声（PA）传感器，用于在间质激光光疗期间进行温度测量。连续波激光和脉冲激光分别用于光热照射和光声温度测量，通过光纤耦合器传输到目标组织。在激光照射期间，测量PA幅度。利用格林爱森参数和生物热方程确定目标组织中关键位置的温度。我们的结果表明，间质PA幅度在22至55°C范围内是温度的线性函数，这已通过热电偶测量得到证实。此外，通过选择合适的激光参数，组织中活性扩散光纤尖端周围的最高温度可控制在41至55°C范围内。因此，这种传感器有可能用于快速、准确和便捷的三维温度测量，以及癌症治疗中间质激光光疗的实时反馈和控制。
