ADC值的变化对急性CO中毒迟发性脑病的预测价值

目的利用MR扩散加权成像监测CO中毒家兔模型急性期脑组织ADC值的变化并与病理对照，探讨MR扩散加权成像对CO中毒急性期诊断的价值并尝试寻找一种能预测CO中毒迟发性脑病的指标。方法通过静吸法建立家兔CO中毒模型15只，成功13只。行磁共振功能成像（本文主要探讨MR扩散加权成像）动态观察家兔中毒后1h、第3天、第5天、第7天的脑部损伤情况，动态测量兔脑皮层的ADC值，并结合病理结果分别与中毒前ADC值相对照。与此同时，连续观察染毒家兔临床表现60d，并根据临床表现不同分为两组，即出现迟发性脑病组和未出现迟发性脑病组。结果所有染毒成功家兔在染毒后1h兔脑皮层均出现ADC值不同程度下降，平均ADC值与染毒前对照差别有显著性（P〈0．05），部分出现了异常信号；未出现迟发性脑病的家兔组各时间点脑皮层ADC值与染毒前对照差异均无显著性意义（P〉0．05）；出现迟发性脑病的家兔组染毒后1h脑皮层ADC值与染毒前对照差异有显著性（P〈O．05）。病理表现与影像学表现一致。结论ADC值对评价急性CO中毒的程度具有重要价值，并且可以初步预测CO中毒迟发性脑病发生的可能性。

The Predictive Value of the Change of ADC Value in Delayed Encephalopathy of Acute Carbon Monoxide Poisoning

Objective To apply MR diffusion weighted imaging to monitor the changes of the ADC value of rabbit brain in acute carbon monoxide poisoning and compared with pathology,approaching the diagnosis value of MR diffusion weighted imaging in acute carbon monoxide poisoning and attempting to find a index which can predict the delayed encephalopathy of carbon monoxide poisoning.Methods Established 15 animal(rabbits) models of acute carbon monoxide poisoning by static absorption method,and 13 succeeded.Applying MRI function technique(this article mainly explored MR-DWI) to dynamicly observe the cerebral damage at the first hour,the 3th,5th,and 7th day after poisoning,and measure the ADC value of cerebral cortex,compared with prepoisoning ADC value respectively and combine with pathology.At the same time,repeatedly observed clinical appearance of the poisoned rabbits for 60 days,and separated 2 groups according to the different clinilal apperance.One group occurred delayed encephalopathy and the other group did not.Results All the ADC value of cerebral cortex of poisoned rabbits descended after 1 hour,and the average ADC value had statistical significance(P<0.05) compared with the ADC value of the prepoisoned.Otherwise,in unoccurred delayed encephalopathy group,compared with the ADC value of prepoisoned there was no statistical significance in the different time after poisoned(P<0.05);but in occurred delayed encephalopathy group,the ADC value of cerebral cortex 1 hour after poisoned had statistical significance(P<0.05) compared with the prepoisoned.The pathological findings coincided with the imaging display.Conclusion The ADC value is very important in evaluating the acute CO poisoning,and can initially predict the occurrence of delayed encephalopathy of carbon monoxide poisoning.