口服ALA脑肿瘤光敏诊断的实验研究

The Experimental Research of ALA Taking Orally on Brain Tumor of Photodynamic Diagnosis

目的:探求ALA口服在脑肿瘤光敏诊断中的最佳剂量、口服后最佳诊断时间、效果、阳性率、假阳性率、假阴性率及光谱分析的方法。方法:口服不同剂量的ALA(20mg/kg、40mg/kg、60mg/kg),不同时间(3小时、4小时、5小时、6小时)以激光诱导荧光OMA检测系统测定无脑瘤正常鼠二侧大脑半球,及G422脑胶质母细胞瘤模型的脑肿瘤、正常脑组织的荧光,并经各种方法进行数据处理,寻求脑肿瘤、正常脑组织相对值相差最大的合适的ALA口服剂量及诊断时间。诊断的阳性率、假阳性率、假阴性率。并将标本作病理检查。结果:脑肿瘤、正常脑组织相对值相差最小剂量及时间是在ALA40mg/kg,服ALA后4小时时比值最大。将标本作病理检查,诊断的阳性率为84%、假阳性率10%、假阴性率16%。结论:从实验数据分析口服ALA经OMA荧光光谱分析能作脑肿瘤荧光诊断,剂量以40mg/kg,服ALA后4小时左右作荧光光谱分析较合适。

Objective： The research of the suitable dose of ALA, the diagnostic time after ALA taking orally for brain tumor, and the positive rate, pseudo positive rate, pseudo negative rate of using this method was studied. Methods ： Measure the fluorescence spectrum of tumor and normal brain, when irradiated by laser, at different dose of ALA taking orally （20mg/kg,40mg/kg ,60mg/kg） and different time period after ALA taking orally （ l h,2h,4h,6h,8h,10h, 12h,24h,48h）, By analyzing the spectrum of fluorescence of sample with optical multi - channel analyzer （OMA） to get the relative ratio of tumor and normal tissue at certain wavelength at different dose and diagnostic period. The positive rate, pseudo positive rate, pseudo negative rate of diagnosis were got compared with pathologic diagnosis. Result ：The ratio of Itumor/Inomal, is largest for 40mg/kg and 4h after ALA taking orally, positive rate is 84%, pseudo negative rate is 16%, pseudo positive rate is 10%, as we compared with pathologic diagnosis. Conclusion：Measure the fluorescence spectrum of tumor, normal brain, and analyzing the spectrum of fluorescence with optical multi -channel analyzer （OMA）, the most suitable dose of 40mg/kg of ALA taking orally, and the measure time of taken 4 hours after ALA taking orally were got.