Doccol MCAO线拴可以将脑梗塞体积标准差减少至5%
成功的MCAO模型的脑血流在插入线拴时会有断崖式下降；在拔出线拴后，激光多普勒检测的血流会很快恢复（图A）。采用硬质尼龙鱼线线拴，极易戳破血管，造成蛛网膜下腔出血（Subarachnoid hemorrhage，图B）。手术过程中血管如果被线拴戳破，脑血流不会有断崖式下降，而是缓慢下降；在拔出线拴后，脑血流也不会恢复。造成脑梗塞体积变异的原因还有，不完全的梗塞血管或线拴移位造成的血流下降程度不均一及提前灌注。因此，线栓的质地是MCAO模型稳定的关键。
对于MCAO模型来说，主要有两种线拴，无包被的火焰熔烫圆头线拴及硅胶包被线拴。研究表明(Tsuchiya et al. 2003)，无包被的圆头线拴在MCAO实验过程中可能导致高达40%的蛛网膜下腔出血，而其标准差可能比平均值的50%还要大。另一项技术文章表明(Shimamura et al. 2006a)，硅胶包被线拴要远好于无包被的圆头线拴，其结果更为稳定，即使对于没有经验的实验者来说也是如此。而多聚赖氨酸包被的线拴只能增加死亡率，不能减少梗赛体积的变异程度(Huang et al. 1998)。
Doccol MCAO线拴全部为硅胶包被，圆润、柔软、包被均匀，即使在没有激光多普勒实时检测的情况，也不会将血管戳破。使用自制的硅胶包被的线拴，大鼠(Schmid-Elsaesser et al. 1998)及小鼠(Shah et al. 2006)的脑梗塞体积的标准差均在30%左右。而使用Doccol MCAO线拴可以得到更好的结果。对于大鼠MCAO模型来说，使用Doccol MCAO线拴得到的结果的标准差可达10%-20% （Ruscher et al.2012；Ishizaka et al.2013；Sakata et al.2012；Candelario-Jalil et al. 2008；Khan et al. 2006；Liu et al. 2006；Shimamura et al. 2006b；Solaroglu et al. 2006；Tsubokawa et al. 2007；Tsubokawa et al. 2006a；Tsubokawa et al. 2006b)。对于小鼠来说，使用Doccol MCAO线拴得到的结果的标准差可达5%-10%(Chen et al.2014; Bae et al.2013; Jin et al.2011; Gu et al.2012; Kleinschnitz et al. 2007; Maysami et al. 2008; Pignataro et al. 2007b; Pignataro et al. 2007c)。
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