椎动脉起始位置与穿出颈椎横突孔高度关系的三维CT血管成像研究

目的通过三维CT血管成像(CTA)探讨椎动脉起始位置与穿出颈椎横突孔高度的关系。方法回顾性分析2017年3月至2019年3月河北医科大学第二医院神经外科行头颈上胸部CTA检查的480例患者的临床资料。将图像传输至图像后处理工作站进行骨质和血管重建,观察双侧椎动脉的起源、走行及穿出颈椎横突孔的高度。对于右侧椎动脉起源正常者,根据穿出颈椎横突孔的高度分为C₄、C₅、C₆组,每组随机选取10例分别测量右侧椎动脉起始位置至右侧颈总动脉起始的距离(L1)和右侧甲状颈干的距离(L₂),以L₁/(L₁+L₂)×100%计算椎动脉起始的相对位置。结果480例患者中,457例(95.2%)双侧椎动脉起源位置正常,均起源于锁骨下动脉,另23例(4.8%)起源异常,其中左侧椎动脉起源于主动脉弓19例、左侧颈外动脉1例;右侧椎动脉起源于右侧颈总动脉3例,且均合并迷走右锁骨下动脉。480例患者中,405例(84.4%)双侧椎动脉经C₆横突孔穿出;另75例(15.6%)穿出高度异常,其中左侧34例,经C₃、C₄、C₅、C₇横突孔穿出的分别有1、4、24、4例,直接入枕骨大孔1例;右侧41例,经C₃、C₄、C₅横突孔穿出的有1、14、26例。椎动脉起源异常的患者,左侧椎动脉起自主动脉弓的占比最高(19/20),且多数穿出颈椎横突孔的高度异常(18/19);右侧椎动脉均起自右侧颈总动脉合并迷走右锁骨下动脉(3/3),且穿出颈椎横突孔的高度均异常(3/3)。椎动脉起源正常的患者,96.7%(445/460)的左侧椎动脉穿出颈椎横突孔的高度正常,92.0%(439/477)的右侧椎动脉穿颈椎横突孔高度正常。3组右侧椎动脉起源正常的患者椎动脉起始的相对位置的差异有统计学意义C₄组:(24.3±2.1)%、C₅组:(47.9±6.6)%、C₆组:(77.7±1.7)%,H=20.178,P<0.001]。结论椎动脉起始位置异常时,其穿出颈椎横突孔的高度多异常。右侧椎动脉的起始相对位置越靠近右侧颈总动脉时,穿出颈椎横突孔的高度越高;而越靠近右侧甲状颈干,穿出颈椎横突孔的高度越低。

Three-dimensional CTA study of relationship between the origin of vertebral artery and the height of transverse foramen of cervical vertebra

Objective To investigate the relationship between the origin of vertebral artery and the height of transverse foramen of cervical vertebra using three-dimensional CT angiography(CTA).Methods The clinical data of 480 patients who underwent head,neck and upper chest CTA examinations from March 2017 to March 2019 at Department of Neurosurgery,the Second Hospital of Hebei Medical University were retrospectively analyzed.The images were transferred to the image post-processing workstation for bone and vascular reconstruction,and the origin and course of bilateral vertebral arteries and the height of the vertebral arteries entering the cervical vertebrae transverse foramen were documented.Patients with normal origin of the right vertebral artery were divided into groups C₄,C₃,and C₆ according to the height of vertebral artery entering transverse foramen of cervical vertebra.Ten cases were randomly selected from each group to measure the distance from the origin of right vertebral artery to the origin of right common carotid artery(L₁)and to the right thyroid cervical trunk(L₂).We calculated the relative position of the origin of vertebral artery with L₁/(L₁+L₂)×100%.Results Among 480 patients,457 cases(95.2%)had normal origins of bilateral vertebral arteries which were from the subclavian artery,and the other 23 cases(4.8%)had abnormal origins.Among them,the left vertebral artery originated from the aortic arch in 19 cases,and left vertebral artery originated from the left exteraal carotid artery in 1 case;the right vertebral artery originated from the right common carotid artery in 3 cases,all of which were complicated with aberrant right subclavian artery.Among the 480 patients,405 cases(84.4%)had bilateral vertebral arteries entering the transverse foramen.The remaining 75(15.6%)had vertebral arteries entering the cervical transverse foramen with abnormal height,which was observed on the left side in 34 cases(left vertebral arteries entering transverse foramen of Cj,C₄,C₅,C₇ in 1 case,4 cases,24 cases and 4 cases respectively,and directly entering the foramen magnum in 1 case)and on the right side in 41 cases(right vertebral artery entering C₃,C₄ and C₅ in 1 case,14 cases,26 cases respectively).The height of vertebral artery entering transverse foramen of cervical vertebra was mostly abnormal when the origin of left vertebral artery was abnormal.In patients with abnormal vertebral artery origin,the left vertebral artery originating from the aortic arch accounted for the highest proportion(19/20),and most of the vertebral arteries entered the transverse foramen of cervical vertebra with abnormal height(18/19).The right vertebral artery originating from the right common carotid artery were complicated with aberrant right subclavian artery(3/3),and the height of vertebral artery entering transverse foramen of cervical vertebra was abnormal(3/3).In patients with normal vertebral artery origin,96.7%(445/460)of left vertebral artery entered transverse foramen of cervical vertebra with normal height,and 92.0%(439/477)of the right vertebral artery entered transverse foramen of cervical vertebra with normal height.Comparison of patients with normal right vertebral artery origin in the 3 groups showed statistically significant differences in the relative position of die vertebral artery origin(C₄ group:24.3±2.1%,C₃ group:47.9±6.6%,and C₆ group:77.7±1.7%,H=20.178,P<0.001).Conclusions In case of abnormal origins of vertebral arteries,the heights of vertebral arteries at the transverse foramen of cervical vertebra are mosdy abnormal.When the relative position of origin of right vertebral artery is closer to the right common carotid artery,the height of right vertebral artery at the transverse foramen of cervical vertebra seems higher.When the relative origin of right vertebral artery is closer to the right thyroid cervical trunk,the height of right vertebral artery at the transverse foramen of cervical vertebra seems lower.