Gill R, Sibson N R, Maskell L, Carpenter T A, Hall L D, Pickard J D
Department of Neurosurgery, University of Cambridge School for Clinical Medicine, UK.
NMR Biomed. 1996 Sep;9(6):241-8. doi: 10.1002/(SICI)1099-1492(199609)9:6<241::AID-NBM432>3.0.CO;2-7.
Diffusion-weighted MRI has been used to investigate therapeutic intervention with MK-801 in an animal model of permanent focal cerebral ischaemia. The animals were imaged continuously for 4 h and again at 24 h following occlusion of the middle cerebral artery (MCA) allowing the development of the ischaemic lesion to be monitored continuously in the same animals. An increased DWI signal, seen as a region of hyperintensity, was detected 1 h after MCA-occlusion in the lateral cortex and caudate nucleus in both control and MK-801 (administered at a dose of 3 mg/kg i.p. 5 min post-ischaemia) treated animals. However, the volume of hemispheric and cortical hyperintensity was smaller in the MK-801-treated animals. The area of hyperintensity progressively increased in the control group over the 4 h imaging time and there was also an increase in the area of hyperintensity between 4 and 24 h. At these time points the area of hyperintensity encompassed the dorsolateral cortex and caudate nucleus. MK-801 treated animals also demonstrated some progressive increase in the area of hyperintensity between 1 and 3 h, but no significant increase in the area of hyperintensity was seen after this time. The hyperintense regions at 4 and 24 h were restricted to the so-called 'core areas' of the lesion in MK-801-treated animals. Thus, using DWI the tissue 'at risk' following ischaemia could be identified and the protective effect of therapeutic intervention demonstrated.
扩散加权磁共振成像已被用于研究在永久性局灶性脑缺血动物模型中使用MK-801进行治疗干预的情况。在大脑中动脉（MCA）闭塞后，对动物连续成像4小时，并在24小时时再次成像，从而能够在同一动物中持续监测缺血性病变的发展。在MCA闭塞1小时后，在对照组和MK-801（在缺血后5分钟以3mg/kg的腹腔注射剂量给药）治疗组动物的外侧皮质和尾状核中均检测到DWI信号增加，表现为高信号区域。然而，MK-801治疗组动物的半球和皮质高信号体积较小。在对照组中，高信号区域在4小时的成像时间内逐渐增加，并且在4至24小时之间高信号区域也有所增加。在这些时间点，高信号区域包括背外侧皮质和尾状核。MK-801治疗组动物在1至3小时之间高信号区域也有一些逐渐增加，但在此之后高信号区域没有明显增加。在MK-801治疗组动物中，4小时和24小时时的高信号区域局限于病变的所谓“核心区域”。因此，使用DWI可以识别缺血后“有风险”的组织，并证明治疗干预的保护作用。
