颈动脉分叉与喉上神经外侧支的显微解剖关系研究

Microanatomy relation of carotid artery bifurcation with lateral branch of the superior laryngeal nerve

目的阐述颈动脉分叉与喉上神经外侧支的显微解剖关系，探讨其在颈动脉内膜切除术的价值。方法于2017年1月至2018年1月对10具尸头20侧颈动脉分叉部进行显微解剖，并测量颈动脉分叉到周边骨性结构，喉上神经外侧支与颈外动脉内侧缘交汇点至下颌骨角、喉结节点、乳突尖及颈动脉分叉的距离。结果（1）颈动脉分叉到喉结节点、下颌骨角的垂直距离分别为24.32 mm（18.8-35.78 mm）、13.55 mm（9.26-19.60 mm），至乳突尖的直线距离为68.59 mm （49.48-76.94 mm）。按照喉结节点到颈动脉分叉的垂直距离来判断颈动脉分叉的高度，其与使用Wain测量法得出的结果具有较高的一致性（Kappa值=0.900）。（2）正常分叉标本中喉上神经外侧支与颈外动脉内侧缘交汇点至颈动脉分叉、甲状腺上动脉分叉、下颌骨角、乳突尖的距离分别为17.81 mm（15.24-25.58 mm）、19.42 mm（17.08-29.12 mm）、20.51 mm（17.98-22.20 mm）、71.00 mm（69.00-74.50 mm）；高位分叉标本中分别为6.40 mm（2.44-9.20 mm）、8.84 mm（4.74-10.88 mm）、12.15 mm（10.64-13.54 mm）、60.90 mm（59.80-66.50 mm）。结论颈部喉结节点位置固定，可作为手术切口标记点。对于正常颈动脉分叉患者，术中可将颈动脉分叉前上方1.5 cm作为安全标志界限；对于高位颈动脉分叉患者，手术时应紧贴颈动脉分叉部和甲状腺上动脉外膜进行分离，无安全界限。

ObjectiveTo discuss the microsurgical anatomy of carotid bifurcation and external branch of the superior laryngeal nerve （EBSLN）, and to explore the operative techniques in carotid endarterectomy.MethodsThe carotid bifurcation （20 sides） of 10 cadaveric heads was studied by using microanatomy from January 2017 to January 2018. The distance between bifurcation of carotid artery to peripheral bone structure, and the distances between point of EBSLN to medial margin of the carotid artery to mandibular angle, most prominent point of the larynx, apex of the mastoid, and bifurcation of carotid artery were measured.Results（1） The vertical distance from carotid bifurcation to larynx point and mandibular angle was 24.32 （18.8-35.78） mm and 13.55 （9.26-19.60） mm. The straight distance from carotid bifurcation to mastoid tip was 68.59 （49.48-76.94） mm. According to the vertical distance of larynx point to carotid bifurcation, the height of bifurcation of the carotid artery was consistent with the results of wain measurement （K=0.90）, and the difference was statistically significant （P〈0.05）. （2） The distances between the point of EBSLN to medial margin of the carotid artery to carotid artery bifurcation, upper thyroid artery bifurcation, mandibular angle and mastoid process were 17.81（15.24-25.58） mm, 19.42 （17.08-29.12） mm, 20.51 （17.98-22.20） mm, 71.00 （69.00-74.50） mm in normal bifurcations. Those in the high bifurcation specimens were 6.40 （2.44-9.20） mm, 8.84（4.74-10.88） mm, 12.15（10.64-13.54）, 60.90 （59.80-66.50） mm, respectively. ConclusionsThe position of the laryngeal prominence is fixed, which can be used as a marker for surgical incision. When the vertical distance from the larynx point to the bifurcation of the carotid artery is greater than or equal to 2.5 cm, it is highly bifurcated; the bifurcation is normal when less than 2.5 cm. In patients with normal carotid bifurcation, 1.5 cm of the carotid artery bifurcation can be used as a safety mark limit during the operation. For patients with high carotid artery, the EBSLN is almost parallel to or down the superior thyroid artery, and it should be closely attached to the bifurcation of the carotid artery and the outer membrane of the superior thyroid artery, and there is no safety margin.