Objective: To investigate the value of multiple parameters derived from intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) and three-dimensional arterial spin labeling (3D-ASL) in Ki-67 labeling index (Ki-67 LI) and grading of human brain gliomas. Methods: From December 2015 to May 2018, 45 patients of gliomas confirmed by surgical pathology in Li Huili Hospital, Ningbo Medical Center were divided into low-grade group (20 cases of WHO grade Ⅱ) and high-grade group (12 cases of WHO grade Ⅲ, 13 cases of WHO grade Ⅳ), and the Ki-67 LI of glioma was obtained by immunohistochemistry. All patients, 24 males and 21 females, aged 25-83 years, mean(53±12)years, underwent conventional magnetic resonance imaging (MRI), IVIM-DWI and 3D-ASL before operation, then measured the true water diffusion coefficient (D), microcirculation perfusion coefficient (D(*)), perfusion fraction (f) and cerebral blood flow (CBF) in the tumor solid area and the contralateral normal white matter area. Those parameters and the Ki-67 LI were compared between the low-and high-grade groups with Mann-Whitney U test. Spearman's correlation was used to analyze the correlation between the quantitative parameters and Ki-67 LI. The ROC curve was used to assess the diagnostic efficacy of parameters in the grading assessment of brain gliomas. Results: The D(0.791×10(-3)mm(2)/s) and f (0.261) of the high-grade group were lower than those of the low-grade group, whereas D(*) (4.153×10(-3) mm(2)/s), CBF(102.027 ml·min(-1)·100 g(-1)) and Ki-67 LI (0.25) were higher (P<0.05). There was a moderate negative correlation between D, f and Ki-67 LI(r=-0.513,-0.457, all P<0.05). There was no significant correlation between D(*) and Ki-67 LI (P=0.571). The area under the curve (AUC) for identifying high-and low-grade gliomas by D, D(*), f and CBF values was 0.965, 0.745, 0.842, and 0.830 respectively (all P<0.05). Conclusion: D and f can be used for quantitative prediction of Ki-67 LI. IVIM-DWI and 3D-ASL are helpful in the grading assessment of gliomas, and the diagnostic efficiency of D is the highest.
目的： 探讨体素内不相干运动扩散加权成像（IVIM-DWI）和三维动脉自旋标记（3D-ASL）评估脑胶质瘤Ki-67标记指数（Ki-67 LI）和分级的价值。 方法： 回顾性分析2015年12月至2018年5月宁波市医疗中心李惠利医院经手术病理证实的45例脑胶质瘤患者，男24例、女21例，年龄25~83（53±12）岁，分为低级别组（WHO Ⅱ级20例）和高级别组（WHO Ⅲ级12例、WHO Ⅳ级13例），经免疫组化获得胶质瘤的Ki-67 LI。患者术前均行颅脑MRI常规扫描、IVIM-DWI和3D-ASL检查，测量肿瘤最大层面实性区域和对侧正常白质区域的真性水分子扩散系数（D）、微循环灌注系数（D(*)）、灌注分数（f）和脑血流量（CBF）。利用秩和检验（Mann-Whitney U检验）比较高、低级别组间4个定量参数、Ki-67 LI的差异。采用Spearman法分析4组定量参数与Ki-67 LI之间相关性。采用受试者工作特征（ROC）曲线评估4组定量参数在脑胶质瘤分级的诊断效能。 结果： 高级别组D值（0.791×10(-3)mm(2)/s）、f值（0.261）均低于低级别组，D(*)值（4.153×10(-3)mm(2)/s）、CBF值（102.027 ml·min(-1)·100 g(-1)）及Ki-67 LI（0.25）均高于低级别胶质瘤，差异均有统计学意义（均P<0.05）。D、f与Ki-67 LI呈中度负相关，相关系数r分别为－0.513、-0.457（均P<0.05）；D(*)与Ki-67 LI无明显相关性（P=0.571）。D、D(*)、f和CBF鉴别高、低级别胶质瘤的曲线下面积（AUC）分别为0.965、0.745、0.842和0.830，均P<0.05。 结论： D、f值可定量预测Ki-67 LI，IVIM-DWI和3D-ASL有助于脑胶质瘤的分级评估，D值诊断效能最高。.
Keywords: Glioma; Ki-67 antigen; Magnetic resonance imaging; Spin labels.