Real-Time Identification of Tissue’s Thermal Damage Level Based on Near Infrared Scattering Spectroscopy
DAI Li-juan1，JIA Wei-wei1，QIAN Ai-ping1，HUA Guo-ran1，QIAN Zhi-yu2
1. Department of Mechanical Engineering, Nantong University, Nantong 226019, China
2. Department of Biomedical Engineering，Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China
Abstract：A new method of real-time identification of tissue’s thermal damage level based on near infrared (NIR)scattering spectroscopy was established. Firstly, 808 nm pulse lasers of 3.5, 5, 6.5 and 8 W were introduced separately into fresh in vitro porcine livers to make thermal damage. The NIR scattering spectra and temperatures were acquired respectively during heating at a distance of 10 mm from the center of the damage, and slopes of spectra between 830 and 900 nm (S830~900) were obtained by least-square estimation. Laser was switched off as S830~900 arrived at different times of original values. Secondly, tissues around the spectra sample points were taken to obtain histological analysis, and grades were given according to the tissues’ histological characteristics using 3 grades scoring system (score of 3 means full damage, score of 2 means partial damage and score of 1 means invalid damage). Finally, Correlations among S830~900’s largest rising amplitude during heating and its final steady value after cooling and thermal damage levels were analyzed-. Results showed that a full damage was received generally as S830~900 increased more than 4 times of its original value and finally stabilized at 3.5 times after cooling; an invalid damage was usually obtained as S830~900 increased 2 to 5 times and finally dropped to 1 to 1.5 times; and others could be identified as partial damage. In conclusion, based on the analysis results, relationships between spectra and thermal damage levels were established for the first time. For thermal damage identification, S830~900’s largest rising amplitude during heating combined with its final steady value after cooling has good evaluating effects which can decrease the impact on the results induced by individual differences and make a high accuracy of above 90%. Identification of tissue’s thermal damage level in real-time with a high accurate rate has been achieved, providing a new method for in vivo monitor of tissue thermal damage.
[1] Ioana Smith, Michel Kahaleh. Gastrointestinal Endoscopy Clinics of North America, 2015, 25(4): 793.
[2] Dou Jianping, Yu Jie, Cheng Zhigang, et al. Ultrasound in Medicine & Biology, 2016, 42(8): 1825.
[3] Wang Tao, Zhao Gang, Qiu Bensheng. International Journal of Heat and Mass Transfer, 2015, 90: 81.
[4] Lu Xinwu, Ye Kaichuang, Shi Huihua, et al. Journal of Vascular Surgery, 2011, 54(1): 139.
[5] Curry Daniel J, Gowda Ashok, McNichols Roger J, et al. Epilepsy & Behavior, 2012, 24(4): 408.
[6] LI Xiao-feng, QIAN Guo-jun(李晓峰, 钱国军). Contemporary Medicine(当代医学), 2011, 17(30)：114.
[7] QIAN Zhi-yu, LI Wei-tao(钱志余, 李韪韬). Life Science Instruments(生命科学仪器), 2013, 11(6): 45.
[8] WANG Jin-yang, QIAN Zhi-yu, QIAN Ai-ping, et al(王晋阳, 钱志余, 钱爱平, 等). Chinese Journal of Quantum Electronics(量子电子学报), 2011, 28(1)：91.
[9] Qian Aiping, Hua Guoran, Qian Zhiyu, et al. Chinese Journal of Laser, 2011, 38(1): 0104003.
[10] Dai Lijuan, Hua Guoran, Qian Aiping, et al. Applied Mechanics and Materials, 2012, 121-126: 3998.
