Systematic review on the variability of the human brain arterial territories assessed using neuroimaging methods

Imaging methods for brain arterial territories have evolved significantly from cadaver injection techniques to combinations of CT angiography with multiple MRI perfusion techniques. The variability of the brain arterial territories is well acknowledged in the literature. It has been attributed to: (1) haemodynamic factors related to the peripheral resistance of each artery; (2) anomalies of the Circle of Willis; (3) the involvement of leptomeningeal collateral (LMCs) arteries; and (4) enlargement of arterial territories due to previous stroke; among other factors. We separately conducted two systematic literature reviews searching for papers that 1) acknowledge, illustrate or analyse the vascular supply of the brain territories and the variability of their boundaries; 2) identify and discuss the source of this variability; and 3) present or evaluate useful resources to estimate the boundary of the arterial territories from brain MRI data. Each systematic search had slightly different aim and inclusion/exclusion criteria. This dataset contains the result of the searches and the data extracted. From analysing the data extracted, the primary source of variability in the arterial territories was the involvement of LMCs. These provide emergency blood supply across the surface of the brain, between arterial territories, following occlusion. Secondary sources included variation of the Circle of Willis and enlargement of arterial territories due to previous stroke. After analysing non-contrast FLAIR MRI from 45 stroke patients for border zone and LMCs involvement, inter-observer reliability analysis found the prospect of assessing LMCs from conventional structural MRI sequences to estimate the variability of these territories to be very low (Kappa Statistic = 0.1262). This dataset also includes this inter-observer analysis.

脑动脉供血区域的影像学检查方法已历经显著演进，从早期的尸体灌注造影技术，发展至计算机断层血管造影（CT angiography）与多模态磁共振灌注成像技术的联合应用方案。现有文献已普遍证实脑动脉供血区域存在个体变异，该变异的诱因可归纳为以下几类：（1）与各动脉外周阻力相关的血流动力学因素；（2）大脑动脉环（Circle of Willis）解剖变异；（3）软脑膜侧支（LMCs）动脉的参与；（4）既往卒中导致的动脉供血区域代偿性扩大，以及其他多种因素。

本研究分别开展两项系统综述，检索满足以下条件的相关文献：1）对脑动脉供血分布及其边界变异进行阐述、分析或证实；2）明确并探讨该变异的诱因来源；3）提出或评估可通过脑磁共振成像（MRI）数据估算动脉供血区域边界的实用工具与方法。两项系统检索的研究目标与纳入、排除标准均存在细微差异。本数据集包含上述两项检索的最终结果以及提取得到的全部相关数据。

经对提取数据的分析，脑动脉供血区域变异的首要诱因是软脑膜侧支血管的参与：当动脉发生闭塞后，这类血管可在脑表面不同动脉供血区域之间提供应急血流灌注，以维持局部血供。次要诱因则包括大脑动脉环解剖变异，以及既往卒中引发的动脉供血区域代偿性扩大。

本研究针对45例卒中患者的平扫液体衰减反转恢复（FLAIR）磁共振成像序列进行分析，以识别脑分水岭区与软脑膜侧支血管受累情况；随后开展的观察者间信度分析显示，通过常规结构磁共振成像序列评估软脑膜侧支血管，进而估算脑动脉供血区域变异的可行性极低（Kappa统计量=0.1262）。本数据集同时包含上述观察者间信度分析的相关数据。