Department of Neurosurgery, Tokyo Metropolitan Tama Medical Center, Tokyo, Japan.
Department of Neurosurgery, Tokyo Metropolitan Tama Medical Center, Tokyo, Japan.
World Neurosurg. 2022 Oct;166:e980-e985. doi: 10.1016/j.wneu.2022.08.028. Epub 2022 Aug 11.
Endovascular mechanical thrombectomy (MT) has now evolved to become the standard treatment for acute ischemic stroke due to large vessel occlusion. Arterial perforation is a potential complication of MT, and the risk of this event during blind crossing the occlusion site has been elucidated. The intracranial arterial system shows morphological structural symmetry, so we investigated the utility of the bilateral symmetry of the proximal middle cerebral artery (MCA) as a preprocedural evaluation to predict hidden running course distal to the thrombus.
This study retrospectively analyzed 191 consecutive patients (mean age, 67.5 ± 15.5 years; 100 women) who underwent time-of-flight-magnetic resonance angiography in our institution. Four landmarks of the MCA were assessed: division pattern, early branching pattern, length, and course pattern. Each geometric property was compared between cerebral hemispheres. Frequencies of symmetry and symmetry breaking were assessed.
In 91% (bifurcation type, 87%; trifurcation type, 4%), branching patterns of the left and right M1 were symmetrical. Early frontal and/or temporal branches were observed in 31%, and the presence/absence of early branches was symmetrical in 70% cases. In 19%, M1 was classified as short M1, and classifications were identical between hemispheres in 74%. Running course of the M1 was symmetrical in 63%. Two or more parameters were symmetrical in 181 cases (95%).
The symmetry of bilateral M1-2 structures was demonstrated in most cases from the perspectives of 4 parameters. The MCA symmetry can predict the running course of the MCA before crossing the occlusion site and shows potential benefits for neurointerventionalists.
由于大血管闭塞，血管内机械血栓切除术（MT）现已成为急性缺血性脑卒中的标准治疗方法。动脉穿孔是 MT 的一种潜在并发症，在盲目穿过闭塞部位时发生这种事件的风险已经阐明。颅内动脉系统显示形态结构对称，因此我们研究了近端大脑中动脉（MCA）的双侧对称性作为预测血栓远端隐匿性走行的术前评估的效用。
本研究回顾性分析了在我院进行时间飞跃磁共振血管造影的 191 例连续患者（平均年龄 67.5±15.5 岁，100 例女性）。评估了 MCA 的四个标志：分支模式、早期分支模式、长度和走行模式。比较了每个几何属性的两侧半球之间的差异。评估了对称性和非对称性的频率。
在 91%（分叉类型 87%，三叉类型 4%）的患者中，左、右 M1 的分支模式是对称的。31%观察到早期额部和/或颞部分支，70%的病例早期分支存在/不存在是对称的。19%的 M1 被归类为短 M1，74%的病例左右半球的分类是相同的。M1 的走行在 63%的病例中是对称的。181 例（95%）有 2 个或更多参数是对称的。
从 4 个参数的角度来看，大多数情况下双侧 M1-2 结构的对称性是存在的。MCA 对称性可以预测在穿过闭塞部位之前 MCA 的走行，对神经介入医生有潜在的益处。
