Li F, Han S, Tatlisumak T, Carano R A, Irie K, Sotak C H, Fisher M
Department of Neurology, University of Massachusetts Memorial Health Care, Worcester 01605, USA.
Stroke. 1998 Aug;29(8):1715-9; discussion 1719-20. doi: 10.1161/01.str.29.8.1715.
In-bore middle cerebral artery occlusion (MCAO) enables investigators to acquire preischemic MRI data and to image ischemic changes immediately after occlusion. We have developed a highly successful in-bore MCAO method. This study describes the methods and pertinent techniques.
Sixty-seven Sprague-Dawley rats were subjected to temporary (n=36) or permanent (n=31) MCAO. The occluding device consisted of a supporting tubing, a driving line, and a silicone-coated 4-0 nylon suture occluder. Outside the magnet, the occluder was positioned in the carotid canal. MCAO was achieved in the magnet bore by remotely advancing the driving line until resistance was felt. Diffusion-weighted imaging (DWI) and perfusion-weighted imaging (PWI) were acquired before and immediately after occlusion and were used to document the presence of MCAO.
Fifty-nine (88.1%) rats were successfully occluded, demonstrating hyperintensity on DWI, perfusion deficits on PWI, and no subarachnoid hemorrhage at postmortem examination. The average values of the apparent diffusion coefficient in both the frontoparietal cortex and the lateral caudoputamen significantly decreased as early as 3 minutes after the onset of ischemia. The failures included preocclusion damage (1/67), sliding out of the occluder during occlusion (1/67), no occlusion (2/67), and arterial perforation (4/67).
Our in-bore MCAO method is easily performed and is as successful as MCAO induced outside the magnet.
磁共振成像（MRI）检查孔内大脑中动脉闭塞（MCAO）技术可使研究人员获取缺血前MRI数据，并在闭塞后立即对缺血性改变进行成像。我们已开发出一种非常成功的检查孔内MCAO方法。本研究描述了该方法及相关技术。
对67只Sprague-Dawley大鼠进行暂时性（n = 36）或永久性（n = 31）MCAO。闭塞装置由一根支撑管、一根驱动线和一个硅酮涂层的4-0尼龙缝合闭塞器组成。在磁体外部，将闭塞器置于颈动脉管内。通过远程推进驱动线直至感觉到阻力，在磁体孔内实现MCAO。在闭塞前和闭塞后立即进行扩散加权成像（DWI）和灌注加权成像（PWI），以记录MCAO的存在情况。
59只（88.1%）大鼠成功实现闭塞，在DWI上表现为高信号，PWI上表现为灌注缺损，尸检时无蛛网膜下腔出血。早在缺血发作后3分钟，额叶顶叶皮质和外侧尾状壳核的表观扩散系数平均值就显著降低。失败情况包括闭塞前损伤（1/67）、闭塞过程中闭塞器滑出（1/67）、未实现闭塞（2/67）和动脉穿孔（4/67）。
我们的检查孔内MCAO方法操作简便，与磁体外部诱导的MCAO一样成功。
