Abstract:

Objective To investigate the relationship between the morphology feature of vertebral-basilar artery dissection (VBD) and the degree of posterior circulation perfusion defect in patients with symptomatic intracranial VBD. Methods A retrospective analysis was performed for the multi-modal magnetic resonance imaging data of consecutive patients with intracranial VBD diagnosed by DSA at the First Medical Center of Chinese PLA General Hospital from December 2015 to December 2019. Based on MRA, the morphology of VBD was classified as the following types: artery ectasia type, pearl-and-string type, stenosis-occlusion type; based on MRA and high-resolution vessel wall imaging (HR VWI), the artery stenosis degree was classified as no, mild, moderate and severe, the volume of hypoperfusion area was compared among the above groups based on the morphology and stenosis degree. Results A total of 34 patients were enrolled in this study, including 11 cases (32.3%) of artery ectasia type (volume of hypo-perfusion area: 18.99±21.63 mL), 15 cases (44.1%) of pearl-andstring type (78.31±85.64 mL) and 8 cases (23.5%) of stenosis-occlusion type (28.91±16.88 mL). There was statistical difference in the volume of hypo-perfusion area among the morphology groups, of which the pearl-and-string type group had the most severe perfusion defect. There was no statistical difference in the volume of hypo-perfusion area among the different stenosis degree groups based on MRA or HR VWI. Conclusions The morphology feature of symptomatic intracranial VBD was associated with the changes of brain perfusion defect, and the pearl-and-string type VBD tended to cause more severe perfusion defect in post circulation territory.

Key words: Artery dissection; Magnetic resonance imaging; Perfusion imaging

摘要：

目的 研究颅内椎-基底动脉夹层不同形态类型及不同狭窄程度对后循环缺血的影响。 方法 回顾性分析解放军总医院第一医学中心2015年12月-2019年12月经DSA确诊的椎动脉颅内 段及基底动脉夹层患者的多模式磁共振影像数据，利用MRA对后循环夹层的形态进行分组（瘤样 扩张型、线珠型、狭窄-闭塞型），并根据MRA和高分辨率磁共振管壁成像（high-resolution vessel wall imaging，HR VWI）上各病变狭窄率进行分组（无、轻、中、重度），比较不同分组之间低灌注区容积的 差异。 结果 共纳入颅内椎-基底动脉夹层患者34例。基于MRA的形态学分组，瘤样扩张型11例（32.3%） （低灌注区容积：18.99±21.63 mL）、线珠型15例（44.1%）（低灌注区容积：78.31±85.64 mL）、狭窄- 闭塞型8例（23.5%）（低灌注区容积：28.91±16.88 mL），不同形态分组之间低灌注区容积具有统计 学差异，其中线珠型的低灌注缺损最严重。基于MRA和HR VWI测量的病变血管不同狭窄率分组之间， 低灌注区容积均无统计学差异。 结论 基于MRA的症状性颅内椎-基底动脉夹层形态学可以反映脑组织的灌注缺损变化，其中线珠 型夹层可能引起更为严重的后循环缺血。

关键词: 动脉夹层; 磁共振成像; 灌注成像