MR新技术在原发性中枢神经系统血管炎诊断中的应用

摘要

目的 分析MR新技术在原发性中枢神经系统血管炎(PACNS)中的表现与特征,探讨MR新技术对本病的诊断价值.方法 收集本院临床诊断为PACNS患者17例,所有患者均行T1WI、T2 WI、扩散加权成像(DWI)、TI WI+C等MR常规序列及三维伪连续动脉自旋标记3D PCASL扫描,部分患者行磁共振血管成像(MRA)、磁敏感加权成像(SWI)及磁共振波谱成像(MRS)扫描.基于动脉自旋标记(ASL)原始图像获得脑血流(CBF)图.统计方法采用描述性统计分析,CBF值比较采用独立样本t检验.结果 与健侧相比,PACNS患者病变处血流灌注均明显降低(P=0.000);13例行SWI检查的患者中,10例病变内可见低信号;14例行MRS检查的患者中,10例表现为N-乙酰天门冬氨酸(NAA)峰降低、胆碱(Cho)峰升高,其中2例出现乳酸(Lac)峰.结论 3D PCASL可检测到PACNS病变处血流动力学变化,SWI则对观察病变内微出血情况具有高度敏感性,MRS则可明确病变内神经元破坏程度及修复情况,联合常规影像可明显提高对本病的认识及诊断准确性.%Objective To study imaging findings of primary angiitis of the central nervous system (PACNS) on MR new techniques,and to explore the diagnostic value of MR new techniques in this disease.Methods Seventeen cases who had been clinically diagnosed as PACNS were enrolled.All the cases underwent MR regular scans [T1 WI,T2 WI,diffusion weighted imaging(DWI),enhanced-enhanced T1 WI] and 3D-posudo-continuous arterial spin labeling (3D-PCASL).Some cases were scanned by using magnetic resonance angiography (MRA),susceptibility weighted imaging (SWI) and magnetic resonance spectrum (MRS) techniques.The regional cerebral blood flow (CBF) values were achieved based on ASL.The inter-group difference of the CBF values were analyzed by independent sample t test.Results Compared to the normal site,the CBF values in the lesion site were significant lower on PACNS (P=0.000).Of 13 patients scanned by SWI,10 cases showed low signal in the lesion.Of 14 patients scanned by MRS,10 cases showed N-acetylaspartic acid (NAA) peak decrease and Cho peak increase and 2 cases showed lactic acid(Lac) peak.Conclusion 3D PCASL can detect the hemodynamic abnormalities of PACNS.SWI can improve the ability of sensibility to observe the microbleed inside the lesion.MRS can explicit the extent of destruction and repairment of neurons in the lesion.Combining with the convention MR images can improve the understanding of the disease and the diagnostic accuracy.