Loubinoux I, Volk A, Borredon J, Guirimand S, Tiffon B, Seylaz J, Méric P
Laboratoire de Recherches Cérébrovasculaires, CNRS URA 641, Université Paris VII, France.
Magn Reson Imaging. 1997;15(9):1045-55. doi: 10.1016/s0730-725x(97)00141-0.
Increased water T2 values indicates the presence of vasogenic edema. Decreased apparent diffusion coefficient (ADC) maps reveal ischemic areas displaying cytotoxic edema. ADC and T2 abnormalities spread through the middle cerebral artery (MCA) territory up to 24 h after middle cerebral artery occlusion (MCAO). Also, it was found that ADC and T2 contours closely match at 3.5 and 24 h. Since butanediol reduces vasogenic edema and improves energy status in various models of ischemia, we used these two techniques to investigate putative improvements in cytotoxic and vasogenic edema after permanent MCAO performed on rats. Rats were given no treatment (n = 8), or a treatment with 25 mmol/kg intraperitoneal (i.p.) butanediol (n = 5), 30 min before and 2.5 h after MCAO. Quantitative ADC and T2 maps of brain water were obtained, from which the volumes presenting abnormalities were calculated at various time points up to 24 h. Effects of butanediol on the ADC and T2 values in these areas were determined. Butanediol reduced neither the ADC volume nor the initial ADC decline. However, it reduced T2 volumes by 32% at 3.5 h and 15% at 24 h (p < 0.05), and reduced T2 increase in the striatum at 3.5 h post-MCAO. Therefore, our results show for the first time that a pharmacological agent such as butanediol can delay the development of vasogenic edema but does not limit the development of vasogenic edema but does not limit the development of cytotoxic edema. ADC imaging detects areas of severe metabolic disturbance but not moderately ischemic peripheral areas where butanediol is presumed to be more efficacious.
水的T2值升高表明存在血管源性水肿。表观扩散系数(ADC)图降低显示出存在细胞毒性水肿的缺血区域。在大脑中动脉闭塞(MCAO)后24小时内,ADC和T2异常会扩散至大脑中动脉(MCA)供血区域。此外,研究发现,在3.5小时和24小时时,ADC和T2轮廓紧密匹配。由于丁二醇在各种缺血模型中可减轻血管源性水肿并改善能量状态,我们采用这两种技术来研究大鼠永久性MCAO后细胞毒性和血管源性水肿的假定改善情况。在MCAO前30分钟和MCAO后2.5小时,对大鼠不进行治疗(n = 8),或给予25 mmol/kg腹腔注射(i.p.)丁二醇治疗(n = 5)。获取脑水的定量ADC和T2图,并计算出直至24小时各个时间点出现异常的体积。确定丁二醇对这些区域ADC和T2值的影响。丁二醇既未降低ADC体积,也未减少初始ADC下降。然而,它在3.5小时时使T2体积减少了32%,在24小时时减少了15%(p < 0.05),并在MCAO后3.5小时减少了纹状体中T2的增加。因此,我们的结果首次表明,像丁二醇这样的药物制剂可延迟血管源性水肿的发展,但不限制细胞毒性水肿的发展。ADC成像可检测到严重代谢紊乱区域,但无法检测到假定丁二醇更有效的中度缺血周边区域。