激光光谱技术用于肝病诊断的初步研究

【作者】 李建东；

【导师】 丁建华；

【作者基本信息】 大连理工大学 ， 光学工程， 2004， 硕士

【摘要】 本论文应用激光诱导荧光光谱技术，研究了肝纤维化白鼠及肝硬化患者血清的荧光光谱，通过分析肝纤维化白鼠和对照组白鼠的荧光光谱，以及健康人及肝病变患者血清自体荧光光谱，研究激光光谱技术用于肝病诊断的可能性。 文章在综述了激光光谱技术在医学诊断上应用及发展现状的基础上，使用氩离子激光器为激发光源，利用514.5nm、488.0nm和476.5nm三种波长的激发光激发白鼠（59例——健康8例；肝纤维化51例）及人（17例——健康6例：肝硬化11例）的血清得到荧光光谱。本文计算了荧光的相对强度比、半值宽度，对荧光光谱做了二阶导数，以及谱图分离等处理，对荧光光谱数据作了深入细致的分析。 白鼠与人血清荧光光谱的二阶导数光谱分析表明，在488.0nm及476.5nm的激发光作用下，在490-600nm的范围内，血清荧光光谱的二阶导数光谱在528nm（人血清出现在513nm）、553nm、587nm附近出现极小值。健康时前两个极小值的比比肝病变时要小，使用该参量区分样品时，得到约80％的符合率；对荧光光谱进行非线性高斯拟合处理，得到了相似的结果。 对人血清的荧光光谱，除进行了二阶导数分析外，还计算了相对强度比和强度为最大强度1／2倍时所对应的带宽(W_1／2)。发现，488.0nm激发的荧光光谱，健康组相对强度比I₅₀₀／I₆₀₀的值较病变组小，健康组的带宽W_1／2明显大于病变组（平均值大约大于4.2nm）；激发光为476.5nm时，健康组相对强度比I₄₉₀／I₆₀₀的值较病变组大，健康组的带宽(W_1／2)明显大于病变组（平均值大约大于4.2nm）。 文章在查阅了大量相关文献的基础上，认为肝病变时相对强度比的变化，与肝病变时血清中胆红素（荧光峰位于515nm附近）和卟啉衍生物（荧光峰位于590-630nm）的升高有关，并认为，这一光谱改变可能是肝病变时，血清荧光光谱的特征改变。在本实验的条件下，分析卟啉类衍生物荧光强度的变化以476.5nm作激发光结果较好，而研究胆红素的荧光强度变化则以488.0nm的激发光为佳，另外导数分析法是一种分析肝病变血清荧光光谱的有效方法。更多还原

【Abstract】 Laser-induced auto-fluorescence spectra of serum of hepatocirrhosis patients and liver fibrosis rats are investigated in this paper. The purpose is to find difference between serum of healthy human and liver diseases patients in fluorescence spectra and to study whether the laser-induced auto-fluorescence spectra may diagnose liver diseases.Fluorescence spectra of serum were collected at the excitation of Ar-ion laser (514.5nm, 488.0nm and 476.5 nm). The spectra were analyzed to calculate relative intensity ratio, bandwidth, as well as the second derivative spectra and Multi-peak Gauss fit of fluorescence spectrum.The results of the second derivative spectra analysis indicate that there are three minimum values near 528nm (515nm/human), 553nm and 587nm from 490nm to 600nm. The ratio of the first and second minimum values of health is smaller than that of disease. Multi-peak Gauss fit of fluorescence spectrum may obtain similar reslut.Besides analyzing the second derivative spectra, the relative intensity ratio and bandwidth of fluorescence spectra of serum of hepaocirrhosis patients were calculated. The results indcate that the relative intensity ratio(I500/I600) of healthy serum is smaller than that of disease at 488.0nm excitation, whereas the ratio(I490/I600) is larger at 476.5nm excitation. At the same time, the bandwidth of health is larger than that of disease at 488.0nm and 476.5nm excitation.The paper has analyzed the main fluorescent materials from 490nm to 640nm, and considers that difference of spectra between health and disease is due to difference of the concentration of bilirubin (fluorescent peak lie near 515nm) and porphyrin derivative (fluorescent peak lie 590-630nm), and the difference is characteristic change of fluorescence spectrum of liver disease serum. At the same time, the result indicates when intensity change of fluorescence of porphyrin derivative is analyzed, 476.5nm excitation should be used, whereas intensity change of fluorescence of brilrubin is analyzed, 488.0nm excitaion should be used, and the derivative spectra of serum is an effective method to analyse liver disease.更多还原