摘要
目的探讨 MR 扩散加权成像(DWI)对兔一氧化碳(CO)中毒迟发性中毒脑病的预测价值。方法健康大耳白兔60只,用自制 CO 染毒柜吸入染毒,兔昏迷后停止 CO 气体通入,保持染毒柜处于密闭状态6 h。于染毒前及染毒后1 h,3、5、7、15、30、45和60 d 分别行轴面及矢状面 T_2WI、轴面 T_1WI 和 DWI 检查。未出现迟发性中毒脑病症状组(未出现组)的实验兔观察至60 d 为实验终点;出现了迟发性中毒脑病症状组(出现组)的实验兔观察至30～45 d 为实验终点。观察兔脑中毒前后大脑皮层 ADC 值变化规律,探讨 ADC 值变化与迟发性中毒脑病的关系。结果未出现组15只兔于染毒后1 h ADC 值[(7.58±0.36)×10^(-4)mm^2/s]较染毒前[(8.02±0.35)×10^(-4)mm^2/s]降低(q=0.4441,P<0.01);染毒后5 d[(7.84±0.39)×10^(-4)mm^2/s]开始逐渐恢复,染毒后60 d 恢复至染毒前的水平(P>0.05)。出现组15只兔在染毒后1 h ADC 值[(7.40±0.32)×10^(-4)mm^2/s]较染毒前[(8.08±0.32)×10^(-4)mm^2/s]明显降低(q=0.6728,P<0.01)。染毒后5 d[(7.88±0.44)×10^(-4)mm^2/s]恢复接近染毒前水平,7 d 又开始下降,15 d 下降最明显[(7.29±0.93)×10^(-4)mm^2/s],至实验终点未能恢复,染毒后15 d 较染毒前相比差异有统计学意义(q=0.7850,P<0.01)。结论 ADC 值下降程度与脑组织损害程度存在着相关性;急性期 ADC 值下降程度能预测迟发性中毒脑病的出现可能性,15 d ADC 值再次明显下降提示出现了迟发性中毒脑病。
Objective To investigate the value of diffusion weighted imaging （DWI）in predicting delayed encephalopathy of the rabbits brain after carbon monoxide（CO） poisoning. Methods Sixty healthy rabbits were put into seff-made poisoning cabinet and were poisoned by inhalation of CO. Aeration of CO was stopped when the rabbits became comatous, and the cabinet was kept airpoof for 6 h. The rabbits underwent MRI before poisoning , at 1 h, 3 d, 5 d, 7 d, 15 d, 30 d ,45 d, and 60 d after poisoning respectively. Axial and sagittal T2WI, axial T1WI and DWI were performed. In the rabbits that did not show symptoms of delayed encephalopathy, the observation was discontinued on the 60^th day. In the rabbit that showed the symptoms, the observation was discontinued on the 30^th-45^th day. The changing pattern of cortical ADC values before and after CO poisoning was observed and its relationship with delayed encephalopathy was investigated. Results In the group without delayed encephalopathy（ 15 rabbits）, the ADC value at 1 h after poisoning [ （7.58±0. 36）×10^-4 mm^2/s] decreased significantly compared with the pre- poisoning value [ （8.02 ± 0. 35）×10^-4 mm^2/s ] （ q = 0. 4441, P 〈 0.01 ）, retured to the baseline at 5 d [ （ 7. 84 ± 0.39）×10^-4 mm^2/s], and maintained at the same level as pre- poisoning at 60 d after poisoning （P 〉0.05）. In the group with delayed encephalopathy（ 15 rabbits）, the ADC value at 1 h after poisoning [ （7.40 ±0. 32）×10^-4 mm^2/s] decreased significantly compared with the pre- poisoning value[ （8.08 ± 0. 32）×10^-4 mm^2/s] （q = 0. 6728, P 〈 0. 01 ）, returned to the level close to pre- poisoning at 5 d [ （7.88 ±0. 44）×10^-4 mm^2/s], secondly significantly decreased at 15 d [ （7.29 ±0.93） ×10^-4 mm^2/s] without further recovery. The ADC value decrease at 15d after poisoning [ （7.29 ± 0.93 ）×10^-4 mm^2/s ] was significant compared with the prepoisoning ADC value （q = 0. 7850,P 〈 0. 01 ）. Conclusions There is a correlation between the decrease of the ADC value and the degree of tissue damage. The decrease of the ADC value in acute stage can predict the delayed encephalopathy. The second significant decrease of the ADC value at 15 d indicate the development of delayed encephalopathy.
出处
《中华放射学杂志》
CAS
CSCD
北大核心
2007年第10期1129-1133,共5页
Chinese Journal of Radiology
基金
国家自然科学基金资助项目（30260096）
关键词
一氧化碳中毒
磁共振成像
兔
对比研究
Carbon monoxide poisoning
Magnetic resonance imaging
Rabbits
Comparative study
