椎动脉颅内段重复变异MR血管成像的观察分析

目的 探讨椎动脉颅内段重复变异的发生率、磁共振血管成像（MRA）表现特点及其临床意义。方法 回顾性研究。纳入2011年1月—2020年12月聊城市人民医院38 503例患者和体检者的头颈联合或颅脑三维（3D）时间飞跃法（TOF）MRA扫描及最大密度重建（MIP）资料,其中男21 048例、女17 455 例,年龄2~96（63±8）岁;行头颈联合3D TOF MRA检查35 546例,行颅脑3D TOF MRA检查2 957例。观察并统计椎动脉颅内段重复变异的发生率,进而分析椎动脉颅内段重复变异的MRA特点,测量椎动脉重复分支的路径长度,同时记录伴随的头颈部其他血管异常。结果 38 503例受检者中,共发现椎动脉颅内段重复变异36例,检出率为0.093%。左侧13例,右侧23例;重复分支均汇入基底动脉17例,分别汇入基底动脉及对侧椎动脉19例;重复近侧分支的行径长度为（0.64±0.32）cm,远侧分支路径长度为（1.06±0.57）cm。6例合并头颈部其他血管变异：2例合并开窗变异,其中1例开窗发生在重复分支,1例发生在对侧椎动脉;2例合并左侧椎动脉起源于主动脉弓;1例合并动脉瘤;1例合并大脑动脉A1段缺如。1例并发急性脑梗死。结论 椎动脉颅内段重复变异发生率低,通过3D TOF MRA检查可清晰显示椎动脉颅内段重复及其合并的头颈部其他血管异常;在进行后颅窝外科手术或血管介入治疗之前,通过3D TOF MRA扫描检出这种血管变异,更有助于治疗方案的制定。

Observation of magnetic resonance angiography for duplication of the intracranial segment of the vertebral artery

Objective To evaluate the incidence and analyze the magnetic resonance angiography (MRA) characteristics of duplication of the intracranial segment of the vertebral artery. Methods A total of 38 503 cases of head and neck MRA or head three dimensional (3D) time-of-flight (TOF) MRA and maximum density reconstruction images completed in Liaocheng People's Hospital from January 2011 to December 2020 were retrospectively reviewed. There were 21 048 males and 17 455 females with age ranging from 2 to 96 (63±8) years. A total of 35 546 cases underwent 3D TOF MRA of the head and neck, and 2 957 cases underwent 3D TOF MRA of the head. The incidence of duplication variations in intracranial segments of the vertebral artery was analyzed, and then their characteristics were analyzed. The path length of repeated branches of the vertebral artery was measured, and the coexisting abnormalities of other blood vessels in the head and neck were recorded. Results Among 38 503 cases, 36 cases of duplication of the intracranial segment of the vertebral artery were detected, and the prevalence was 0.093%. Thirteen cases were located on the left, and 23 cases were located on the right. Both repeated branches merged into the basilar artery in 17 cases, and the two repeated branches merged into the basilar artery and contralateral vertebral artery in 19 cases, respectively. The path lengths of the proximal and distal branches were (0.64±0.32) cm and (1.06±0.57) cm, respectively. Six cases coexisted with other variants of head and neck vessels. Two cases coexisted with fenestration, one of which was located in one of the repeated vessels and the other was located in the contralateral vertebral artery. Two cases coexisted with the left vertebral artery arising from the aortic arch. One case coexisted with aneurysm. One case coexisted with the absence of the A1 segment of the anterior cerebral artery. One case was associated with acute cerebral infarction. Conclusion The duplication of the intracranial segment of the vertebrae artery is rare and has a low incidence. 3D TOF MRA could clearly display intracranial vertebral artery duplication and other vascular abnormalities of the head and neck. Understanding these vascular variations could help to plan for treatment before posterior fossa surgery or vascular intervention.