扩散加权成像和波谱分析在原发性中枢神经系统淋巴瘤中的应用  

Primary Central Nervous System Lymphoma Characterization by Diffusion- weighted Imaging and MR Spectroscopy

作　　者：陈兵[1] 李辉[2] 李春花[3] 石洋洋 孙涛[3] 

机构地区：[1]宁夏医科大学总医院放射科,银川750004 [2]宁夏医科大学总医院心脑血管病医院放射科,银川750002 [3]宁夏医科大学,银川750004

出　　处：《宁夏医科大学学报》2015年第3期272-276,I0003,共6页Journal of Ningxia Medical University

基　　金：宁夏自然科学基金(NZ09220)

摘　　要：目的探讨扩散加权成像(diffusion-weighted imaging,DWI)和磁共振波谱(MR spectroscopic,MRS)在免疫正常人群原发性中枢神经系统淋巴瘤(primary central nervous system lymphoma,PCNSL)磁振诊断中的应用价值。方法收集2005年5月至2014年4月,免疫正常人群经组织病理学确诊的PCNSL 29例,进行回顾性分析。DWI检查29例(b值为0,1000s/m2),病灶实质和对侧相对正常脑组织进行ADC值测量。MRS做了24个病灶部位,18个病灶采用单体素点分辨波谱采集(PRESS-SV;TR/TE 1500/35或TR/TE 1500/144),6个病灶采用多体素2D化学位移成像(2D-CSI;TR/TE 1000/35)。结果 PCNSL瘤体实质区域弥散受限,ADC值为0.67±0.041×10-3mm2·s-1。MRS见肿瘤实质区域的代谢比率为Cho/Cr=2.06±0.48,NAA/Cho=0.84±0.17,NAA/Cr=1.76±0.56,乳酸和脂质峰的存在达91%(22/24)。病变位于基底节区12例,皮质下白质10例,胼胝体4例,脑室旁2例,小脑1例,累及两个及两个以上部位达60%(18/29)。结论免疫正常人群PCNSL脑内常为多发病灶,以幕上多见,好发于近中线深部脑白质区。在DWI图像上瘤体实质区域弥散受限,ADC值降低。MRS上有乳酸和脂质峰的存在,Cho/Cr比率升高,对淋巴瘤的诊断有重要价值。Objective To clarify the diffusion- weighted imaging（ DWI） and magnetic resonance spectroscopy（ MRS） findings in primary central nervous system lymphoma（ PCNSL） of immunocompetent individuals.Methods 29 immunocompetent individuals with primary central nervous system lymphoma who were pathologically confirmed in our hospital from May,2005 to April,2014 were selected and all the imaging data were retrospectively evaluated. 29 cases performed DWI（ b is 0,1000s·mm- 2） and then measuring the ADC values of substantial parts of the tumors and contralateral normal white matter areas. MRS was performed in 24 positions,among them 18 lesions used single- voxel point- resolved spectroscopy acquisition（ PRESS- SV;TR / TE 1500 /35 or TR / TE 1500 /144）,and the rest ones were used multi- voxel 2D chemical shift imaging（ 2D- CSI; TR/TE 1000 /35）. Results Tumor parenchyma had restricted diffusion on DWI and the mean ADC value was 0. 67 ± 0. 041 × 10- 3mm2·s- 1. MRS findings suggested that tumor metabolic ratios were Cho / Cr = 2. 06 ± 0. 48,NAA / Cho = 0. 84 ± 0. 17,NAA / Cr = 1. 76 ± 0. 56,and the ratio of the presence of lipid / lactate was up to 91%（ 22 /24） in parenchyma. Lesions located in the basal ganglia 12 cases,subcortical white matter 10 cases,corpus callosum 4 cases,periventricular 2 cases,and the other cases in the cerebellum,and up to 60% of cases（ 18 /29） showed two or more parts involved. Conclusion PCNSL of immunenormal population often performed multiple lesions in brain,always occurred in the deep white matter near the midline and it was common to the supratentorial. Tumor parenchyma had restricted diffusion on DWI and decreased ADC values. We found lactic acid and lipid peaks in MRS,and the ratio of Cho / Cr increased,which were significant for diagnosis of lymphoma.

关 键 词：原发性中枢神经系统淋巴瘤 扩散加权成像 磁共振波谱成像 

分 类 号：R739.41[医药卫生—肿瘤] R445.2[医药卫生—临床医学]