Kurabe Satoshi, Okamoto Kouichirou, Suzuki Kiyotaka, Matsuzawa Hisothi, Watanabe Masaki, Suzuki Yuji, Nakada Tsutomu, Fujii Yukihiko
Department of Neurosurgery and Center for Integrated Human Brain Science, Brain Research Institute, University of Niigata, Niigata, Japan.
Cerebrovasc Dis. 2016;41(5-6):256-64. doi: 10.1159/000443538. Epub 2016 Feb 2.
In patients with cerebral infarction, identifying the distribution of infarction and the relevant artery is essential for ascertaining the underlying vascular pathophysiological mechanisms and preventing subsequent stroke. However, visualization of the basal perforating arteries (BPAs) has had limited success, and simultaneous viewing of background anatomical structures has only rarely been attempted in living human brains. Our study aimed at identifying the BPAs with 7T MRI and evaluating their distribution in the subcortical structures, thereby showing the clinical significance of the technique.
Twenty healthy subjects and 1 patient with cerebral infarction involving the posterior limb of the internal capsule (ICpost) and thalamus underwent 3-dimensional fast spoiled gradient-echo sequence as time-of-flight magnetic resonance angiography (MRA) at 7T with a submillimeter resolution. The MRA was modified to detect inflow signals from BPAs, while preserving the background anatomical signals. BPA stems and branches in the subcortical structures and their origins were identified on images, using partial maximum intensity projection in 3 dimensions.
A branch of the left posterior cerebral artery (PCA) in the patient ran through both the infarcted thalamus and ICpost and was clearly the relevant artery. In 40 intact hemispheres in healthy subjects, 571 stems and 1,421 branches of BPAs were detected in the subcortical structures. No significant differences in the numbers of stems and branches were observed between the intact hemispheres. The numbers deviated even less across subjects. The distribution analysis showed that the subcortical structures of the telencephalon, such as the caudate nucleus, anterior limb of the internal capsule, and lenticular nucleus, were predominantly supplied by BPAs from the anterior circulation. In contrast, the thalamus, belonging to the diencephalon, was mostly fed by BPAs from the posterior circulation. However, compared with other subcortical structures, the ICpost, which marks the anatomical boundary between the telencephalon and the diencephalon, was supplied by BPAs with significantly more diverse origins. These BPAs originated from the internal carotid artery (23.1%), middle cerebral artery (38.5%), PCA (17.3%), and the posterior communicating artery (21.1%).
The modified MRI method allowed the detection of the relevant BPA within the infarcted area in the stroke survivor as well as the BPAs in the subcortical structures of living human brains. Based on in vivo BPA distribution analyses, the ICpost is the transitional zone of the anterior and posterior cerebral circulations.
在脑梗死患者中，确定梗死灶的分布及相关动脉对于明确潜在的血管病理生理机制和预防后续卒中至关重要。然而，基底穿支动脉（BPAs）的可视化效果有限，在活体人脑同时观察其背景解剖结构的尝试也很少。我们的研究旨在通过7T磁共振成像（MRI）识别BPAs并评估其在皮质下结构中的分布，从而显示该技术的临床意义。
20名健康受试者和1名患有累及内囊后肢（ICpost）和丘脑的脑梗死患者接受了7T的三维快速扰相梯度回波序列作为时间飞跃磁共振血管造影（MRA），分辨率为亚毫米级。对MRA进行了改进，以检测来自BPAs的流入信号，同时保留背景解剖信号。利用三维部分最大强度投影在图像上识别皮质下结构中的BPA主干和分支及其起源。
该患者左侧大脑后动脉（PCA）的一个分支穿过梗死的丘脑和ICpost，显然是相关动脉。在40个健康受试者的完整半球中，在皮质下结构中检测到571个BPA主干和1421个分支。完整半球之间在主干和分支数量上未观察到显著差异。受试者之间的差异更小。分布分析表明，端脑的皮质下结构，如尾状核、内囊前肢和豆状核，主要由来自前循环的BPAs供血。相比之下，属于间脑的丘脑主要由来自后循环的BPAs供血。然而，与其他皮质下结构相比，标志着端脑和间脑解剖边界的ICpost由起源明显更多样化的BPAs供血。这些BPAs起源于颈内动脉（23.1%）、大脑中动脉（38.5%）、PCA（17.3%）和后交通动脉（21.1%）。
改进后的MRI方法能够在卒中幸存者的梗死区域内检测到相关的BPA，以及在活体人脑皮质下结构中检测到BPAs。基于活体BPA分布分析，ICpost是大脑前、后循环的过渡区。
