da Costa Leodante, Shah-Basak Priyanka P, Dunkley Benjamin T, Robertson Andrew D, Pang Elizabeth W
Division of Neurosurgery, Department of Surgery, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada.
Department of Diagnostic Imaging, The Hospital for Sick Children, Toronto, ON, Canada.
Front Neurol. 2018 Jun 26;9:494. doi: 10.3389/fneur.2018.00494. eCollection 2018.
Aneurysmal subarachnoid hemorrhage (aSAH) accounts for less than 5% of strokes but is associated with significant morbidity and mortality. Amongst survivors, neurocognitive complaints are common, often despite normal imaging. We used magnetoencephalography (MEG) to investigate neurophysiological function during a visual working memory task in aSAH survivors with good recovery and normal structural imaging. Patients with aSAH treated with coiling and exhibiting good outcome measured by Glasgow Outcome Scale (GOS) and without related parenchymal structural lesions in post-treatment MRI, were recruited and compared to age- and sex-matched controls. All participants underwent intelligence and cognitive screening, structural MRI, and MEG testing in conjunction with a 1-back visual working memory task. Sensor-level global field power and virtual electrode source analysis of neuronal activity and connectivity in aSAH were assessed. Thirteen patients and 13 matched controls were enrolled (age: 56 ± 11 years, 19 female). The 1-back task was completed with similar accuracy despite a trend for a longer reaction time in aSAH patients ( = 0.054). During encoding and recognition phases, aSAH patients showed significantly increased neuronal activation and hyperconnectivity in periventricular areas, specifically the anterior and posterior cingulate gyri. Increased posterior and anterior cingulate gyri neuronal activity is demonstrated in aSAH patients during visual working memory tasks, in the absence of structural lesions. These areas work mainly as a hub to "organize" memory storage and retrieval. Increased activity in these areas might be compensatory due to injury and consequently loss of neuronal response in connected areas in the working memory networks.
动脉瘤性蛛网膜下腔出血（aSAH）占中风病例的比例不到5%，但却与显著的发病率和死亡率相关。在幸存者中，神经认知方面的主诉很常见，即便影像学检查结果正常也是如此。我们利用脑磁图（MEG）对恢复良好且结构影像学正常的aSAH幸存者在视觉工作记忆任务期间的神经生理功能进行了研究。招募了采用线圈栓塞治疗且根据格拉斯哥预后量表（GOS）评估预后良好、治疗后MRI无相关脑实质结构性病变的aSAH患者，并与年龄和性别匹配的对照组进行比较。所有参与者均接受了智力和认知筛查、结构MRI检查以及与1-back视觉工作记忆任务相结合的MEG测试。对aSAH患者神经元活动和连接性的传感器级全域场功率及虚拟电极源分析进行了评估。共纳入了13例患者和13名匹配的对照者（年龄：56±11岁，19名女性）。尽管aSAH患者的反应时间有延长趋势（P=0.054），但他们完成1-back任务的准确率相似。在编码和识别阶段，aSAH患者在脑室周围区域，特别是前扣带回和后扣带回，显示出神经元激活显著增加和连接增强。在视觉工作记忆任务期间，aSAH患者在没有结构性病变的情况下，后扣带回和前扣带回的神经元活动增加。这些区域主要作为一个“组织”记忆存储和检索的枢纽发挥作用。这些区域活动的增加可能是由于损伤导致的代偿，进而导致工作记忆网络中相连区域神经元反应丧失。
