Table_5_Resting-State Electroencephalography Functional Connectivity Networks Relate to Pre- and Postoperative Language Functioning in Low-Grade Glioma and Meningioma Patients.docx

Introduction: Preservation of language functioning in patients undergoing brain tumor surgery is essential because language impairments negatively impact the quality of life. Brain tumor patients have alterations in functional connectivity (FC), the extent to which brain areas functionally interact. We studied FC networks in relation to language functioning in glioma and meningioma patients.
Method: Patients with a low-grade glioma (N = 15) or meningioma (N = 10) infiltrating into/pressing on the language-dominant hemisphere underwent extensive language testing before and 1 year after surgery. Resting-state EEG was registered preoperatively, postoperatively (glioma patients only), and once in healthy individuals. After analyzing FC in theta and alpha frequency bands, weighted networks and Minimum Spanning Trees were quantified by various network measures.
Results: Pre-operative FC network characteristics did not differ between glioma patients and healthy individuals. However, hub presence and higher local and global FC are associated with poorer language functioning before surgery in glioma patients and predict worse language performance at 1 year after surgery. For meningioma patients, a greater small worldness was related to worse language performance and hub presence; better average clustering and global integration were predictive of worse outcome on language function 1 year after surgery. The average eccentricity, diameter and tree hierarchy seem to be the network metrics with the more pronounced relation to language performance.
Discussion: In this exploratory study, we demonstrated that preoperative FC networks are informative for pre- and postoperative language functioning in glioma patients and to a lesser extent in meningioma patients.

引言：脑肿瘤手术患者的语言功能保留至关重要，因为语言障碍会严重降低患者的生活质量。脑肿瘤患者存在功能连接（functional connectivity, FC）异常，即脑区间功能交互的程度发生改变。本研究针对胶质瘤与脑膜瘤患者，探究其功能连接网络与语言功能的关联。
方法：本研究纳入15例低级胶质瘤（low-grade glioma）及10例脑膜瘤（meningioma）患者，这些肿瘤均浸润或压迫语言优势半球；所有受试者均在术前及术后1年接受全面的语言功能评估。研究分别在术前、术后（仅胶质瘤患者）采集静息态脑电图（resting-state EEG），同时为健康受试者采集一次静息态脑电图。在对θ频段与α频段的功能连接进行分析后，本研究通过多种网络指标对加权网络及最小生成树（Minimum Spanning Trees）进行量化。
结果：术前胶质瘤患者的功能连接网络特征与健康受试者无显著差异。但胶质瘤患者术前的枢纽节点存在、更高的局部与全局功能连接，不仅与术前较差的语言功能相关，还可预测术后1年的语言表现更差。对于脑膜瘤患者而言，更高的小世界属性与枢纽节点存在均与较差的语言表现相关；而更高的平均聚类系数与全局整合程度，则可预测术后1年的语言功能结局更差。平均离心度、网络直径与树层级，似乎是与语言表现关联最为显著的网络指标。
讨论：本探索性研究表明，术前功能连接网络可有效预测胶质瘤患者的术前及术后语言功能，而对脑膜瘤患者的预测价值相对较低。