摘要
目的:通过观察大鼠实验性出血性脑水肿的MRI动态变化,分析亚低温对脑水肿的干预效果。方法:实验于2004-03/2005-04在徐州医学院神经生物学教研室和徐州医学院附属医院核磁共振室完成。选用22只健康SD雄性大鼠,按完全随机设计的方法分为3组,亚低温组、对照组、假手术组分别为9,10和3只。亚低温组与对照组组大鼠苍白球注射胶原酶造成脑出血模型,假手术组不注射药物。亚低温组大鼠随即放至装有冰袋的纸箱中降温,使肛温维持在(32±1)℃;对照组及假手术组使体温维持在(37±1)℃。通过观察MRI[T1,T2,FLAIR(液体衰减反转恢复序列)]的相关指标计算各组大鼠的血肿吸收率[血肿吸收率=(出血后1d的血肿体积-出血后7d的血肿体积)/出血后1d的血肿体积×100%]、水肿吸收率(计算方法同血肿吸收率)、信号强度比(反应脑水肿的相对含水量,T2WI,FLAIR序列信号强度比越高,含水量越多)及信号强度比相对变化率(计算方法同血肿吸收率)。结果:因死亡及MRI显示血肿过小等原因,最后进入结果分析亚低温组、对照组、假手术组分别为6,6和3只。①亚低温组大鼠的血肿吸收率显著高于对照组[(68.27±6.14)%,(61.19±4.19)%(P<0.05)]。②亚低温组大鼠的水肿吸收率显著高于对照组[(53.88±9.45)%,(40.75±5.01)%(P<0.01)]。③假手术组大鼠左右侧大脑半球各序列信号强度相比,差异无显著性意义(P>0.05)。各个时间点亚低温组大鼠T2WI,FLAIR序列的信号强度比均明显低于对照组(P<0.01)。亚低温组大鼠T2WI,FLAIR序列的信号强度比相对变化率显著高于对照组(t=5.038,4.629,P<0.01)。结论:亚低温可促进大鼠脑出血模型脑内血肿及水肿的吸收,可减低T2WI,FLAIR序列水肿区的信号强度,提示亚低温可减少水肿区的含水量。
AIM： To analyze the interventional effect of mild hypothermy on cerebral edema through observing the dynamic changes of MRI in experimental hemorrhagic cerebral edema of rats.
METHODS： The experiment was finished in neurobiology teaching and research section and nuclear magnetic resonance room of the Affiliated Hospital of Xuzhou Medical College from March 2004 to April 2005. Twenty-two well-being male Spragne Dawley rats were selected and divided into three groups by the method of completely random design. There were nine, ten and three rats in mild hypothermy, control and sham operation group. The models of intracerebral hemorrhage （ICH） were established by infusing collagenase into globus pallidus of the rats in mild hypothermy and control groups. Rats of sham operation group were not injected with drug. To reduce the temperature, rats of mild hypothermy group were placed immediately into carton that there were ice bags in it. The anus temperature of rats was mantained at （32±1） ℃ in mild hypothermy group and （37±1） ℃ in sham operation and control groups. Hematoma absorption rate （Hematoma absorption rate equals hematom volume of the first day after hemorrhage minus the volum of seventh day, divided by hematom volum of the first day after hemorrhage ×100%）, edema absorption rate （calculation method was identical with hematoma absorption rate）, signal intensity ratio （SIR, it reflected relative water content of cerebral edema. The highter of signal intensity ratio of T2WI and FLAIR, the more of water content）and relative variance ratio of SIR （calculation method was identical with hematoma absorption rate）was calculated by correlated data through observing the changes of MRI [T1,T2, FLAIR （fluid attented inversion recovery）].
RESULTS： Becauase of death and too little of hematoma that MRI demonstrated, there were six, six and three rats that were analyzed finally in mild hypothermy, control and sham operation groups, respectively. ①The absorption rate of hematoma was significantly higher in the mild hypothermy than the control group [（68.27±6.14）%, （61.19±4.19）%（P 〈 0.05）].②The absorption rate of edema of mild hypothermy group was significantly higher than of the control group[（53.88±9.45）%, （40.75±5.01）%（P 〈 0.01 ）]. ③The signal intensity in each sequence of sham operation group had no significant difference between the left and right cerebral hemisphere （P 〉 0.05）. The FLAIR and T2WI signal intensity ratio of edema area in the mild hypothermy group were obviously lower than in the control group at every point of time（P 〈 0.01）. The relative variance ratio of SIR of T2WI and FLAIR in the mild hypothermy group was significantly higher than that in the control group（t =5.038 ,4.629,P 〈 0.01 ）.
CONCLUSION： Mild hypothermy can accelerate the absorption of intrae-erebral hematoma and edema with regard to the intracerebral hemorrhage models in rats. Furthermore, it can reduce the signal intensity of T2WI and FLAIR in the edema region and that indicates mild hypothermy can reduce water content in the edema region.
出处
《中国临床康复》
CSCD
北大核心
2006年第18期82-85,i0002,共5页
Chinese Journal of Clinical Rehabilitation
基金
江苏省教育厅重点实验室资助课题(K99038)~~
