Ito Masaki, Niiya Yoshimasa, Kojima Masashi, Itosaka Hiroyuki, Iwasaki Motoyuki, Kazumata Ken, Mabuchi Shoji, Houkin Kiyohiro
Department of Neurosurgery, Otaru General Hospital, Wakamatsu 1-1-1, Otaru, 047-8550, Japan.
Department of Neurosurgery, Hokkaido University Graduate School of Medicine, North 15, West 7, Kita-ku, Sapporo, 060-8638, Japan.
Acta Neurochir Suppl. 2016;123:115-22. doi: 10.1007/978-3-319-29887-0_16.
External carotid artery (ECA) positioned laterally to the internal carotid artery (ICA) at the level of the common carotid artery (CCA) bifurcation is occasionally encountered during carotid endarterectomy (CEA). This study aimed to determine the frequency of this phenomenon and provide technical tips for performing CEA.
The study included 199 consecutive patients (209 carotid arteries) who underwent CEA at Otaru Municipal Medical Center in 2007-2014. The position of the ECA with respect to the ICA at the CCA bifurcation was preoperatively rated as either lateral or normal, using three-dimensional computerized tomographic angiography (3-D CTA) anteroposterior projections. Postoperative diffusion-weighted images (DWIs), and postoperative 3-D CTA images were reviewed.
Among the 209 carotid arteries with atherosclerosis, 11 instances (5.3 %) of lateral position of the ECA were detected in 11 patients. Ten of these arteries (91 %) were right-sided (odds ratio 11.1; 95 % confidence interval 1.38-88.9). Wider longitudinal exposure of the arteries was used during CEA, and the CCA and ECA were rotated clockwise or counter clockwise. The ICA lying behind the ECA along the surgical access route was then pulled out laterally and moved to the shallow surgical field. Cross-clamping, arteriotomy, plaque removal, and wall suturing were performed as usual. No cerebral infarcts were detected on postoperative DWIs, and 3-D CTA revealed no CCA and ICA kinking.
Lateral position of the ECA is not extremely rare in patients undergoing CEA for atherosclerosis and may be a congenital variation, although this is still controversial. CEA can be performed safely if the arteries from the CCA to the ICA are rotated, and the ICA is moved to the shallow surgical field under wider longitudinal exposure. Although no postoperative cerebral infarcts were detected, the risk of artery-to-artery embolism resulting from artery repositioning prior to plaque removal should be taken into consideration.
在颈动脉内膜切除术（CEA）过程中，偶尔会遇到颈外动脉（ECA）在颈总动脉（CCA）分叉水平位于颈内动脉（ICA）外侧的情况。本研究旨在确定这种现象的发生频率，并提供进行CEA的技术要点。
该研究纳入了2007年至2014年在小樽市立医疗中心接受CEA的199例连续患者（209条颈动脉）。术前使用三维计算机断层血管造影（3-D CTA）前后位投影将CCA分叉处ECA相对于ICA的位置评定为外侧或正常。回顾术后扩散加权成像（DWI）和术后3-D CTA图像。
在209条患有动脉粥样硬化的颈动脉中，在11例患者中检测到11例（5.3%）ECA呈外侧位置。其中10条动脉（91%）为右侧（优势比11.1；95%置信区间1.38 - 88.9）。在CEA过程中采用了更广泛的动脉纵向暴露，并将CCA和ECA顺时针或逆时针旋转。然后将沿手术入路位于ECA后方的ICA向外牵拉并移至浅手术视野。照常进行交叉钳夹、动脉切开、斑块清除和血管壁缝合。术后DWI未检测到脑梗死，3-D CTA显示CCA和ICA无扭结。
对于因动脉粥样硬化接受CEA的患者，ECA外侧位置并非极为罕见，可能是一种先天性变异，尽管这仍存在争议。如果将从CCA到ICA的动脉旋转，并在更广泛的纵向暴露下将ICA移至浅手术视野，则可以安全地进行CEA。尽管术后未检测到脑梗死，但在斑块清除前动脉重新定位导致动脉到动脉栓塞的风险应予以考虑。
