99Tcm-HL91乏氧显像预测高压氧放疗增敏的可行性

目的99mTc-HL91乏氧显像预测高压氧对肿瘤的放疗增敏情况。方法40只荷H22肝癌小鼠均分为4组，每组10只；①对照组，不进行高压氧治疗，其中5只行99mTc-HL91乏氧显像，5只行照射治疗；②15分钟组；③30分钟组；④60分钟组，后3组小鼠按高压氧后不同时间顺序，其中5只行99mTc-HL91乏氧显像，其余5只行照射治疗。各组显像小鼠通过核医学感兴趣区（regionfinteresting,ROI）技术，计算肿瘤与对侧相应部位放射性比值（T/NT）。图像采集结束后立即处死小鼠，完整剥离肿瘤，称重并计算放射性计数，计算肿瘤微分摄取率（DUR）。各组照射治疗小鼠均记录肿瘤照射后生长天数及小鼠平均存活时间。结果 与对照组比较，15分钟组、30分钟组DUR值、T/NT值、肿瘤及小鼠生长延迟天数，差异有显著性（P<0.05），60分钟组，各数值均未见显著性差异（P>0.05）。结论99mTc-HL91乏氧显像是一种有效预测高压氧增敏效果的方法，且高压氧增敏作用随时间延长逐渐减弱。

Feasibility of'Tcm-HL91 Hypoxia Imaging to Predict the Radiosensitization of Hyperbaric Oxygenation

Objective The purpose of this study was to evaluate whether 99mTc-HL91 hypoxia imagining could forcast the radiosensitization effect of hyperbaric oxygenation to tumor. Methods Forty bearing H22 tumor mices were divided to 4 groups ,10mices/group: ① The control group: 5 mices to carry on 99mTc-HL91 hypoxia imaging, the remained 5 mices to perform radiotherapy;② The 15 minute group;③ The 30 minute group;④ The 60 minute group. The behind three groups 5 mices to carry on 99mTc-HL91 hypoxia imaging, the remained 5 mices to perform radiotherapy according to the different order after hyperbaric oxygen .ROI were drawn around tumor and contralateral muscles in planar images to calculate the T/NT all of imaging mices . The mices were killed immediately after image acquisition , then the tumors were excised,weighted and the radioactivity were measured. Differential uptake ratio(DUR) was computed to quantitate the tracer uptake. Every radiotherapy group mices were observed and recorded the time of the tumors growth and the average survival time of the mices.Results Compared with the control group, the DUR 、T/NT and the delay times of the tumors growth and the mices,the15min group and 30min group suggested significant difference （P<0.05）, 60min group suggested no significant difference（P>0.05）.Conclusion 99mTc-HL91 hypoxia imaging is an effective forecasting effects of hyperbaric oxygen enhancement methods, and the sensitizing effect of hyperbaric oxygen decreased gradually with time.