大脑胶质瘤病的磁共振及磁共振波谱诊断价值

Value of magnetic resonance imaging and magnetic resonance spectroscopy in diagnosis of gliomatosis cerebri

目的探讨磁共振成像(MRI)和磁共振波谱成像(MRS)对大脑胶质瘤病的诊断价值。方法对13例经手术或活组织病理检查证实的大脑胶质瘤病患者的临床表现及MRI平扫、增强、MRS影像学资料进行回顾性分析。MRI常规行T1加权像(T1WI)、T2加权像(T2WI)及液体衰减反转恢复序列(FLAIR),采用时间飞跃法(TOF)的磁共振血管成像(MRA)、T1WI增强扫描。氢质子MRS采用单体素激励回波探测法(STEAM),并分析N-乙酰天门冬氨酸(NAA)、肌酸(Cr)、胆碱复合物(Cho)等物质峰值改变。结果所有病例均侵犯2个或2个以上脑叶,以颞叶、枕叶、胼胝体、基底节和丘脑等部位侵犯受累常见。病变区T1WI呈低或等信号、T2WI呈高或混杂高信号、液体衰减反转恢复序列上为高信号,未见明显坏死、钙化,受累区域脑组织肿胀,占位效应轻。注射钆喷酸葡胺增强扫描示,9例无明显强化,2例斑片状强化,1例结节状强化,1例线状轻度强化。病变区域MRS表现为不同程度NAA降低,NAA/Cr比值降低;Cho上升,Cho/Cr和Cho/NAA比值上升。结论 MRI结合MRS对大脑胶质瘤病的诊断及鉴别诊断具有较大临床价值,是目前诊断大脑胶质瘤病的首选影像学方法。

Objective To evaluate the value of magnetic resonance imaging（MRI） and magnetic resonance spectroscopy（MRS） in diagnosis and differential diagnosis of gliomatosis cerebri. Methods Clinical representation,MRI and MRS imaging results of 13 patients with gliomatosis cerebri who were confirmed by biopsy or operation were reviewed retrospectively.Routine MRI with time 1 weight imaging（T1WI）,time 2 weight imaging（T2WI）,fluid attenuation inverse recovery（FLAIR） and MRA with time of fly（TOF） together with contrast enhancement MRI were performed.Single voxel was chosen for the 1H MRS acquisition at lesion and normal areas with STEAM sequence.The changes of the N-acetylaspartate（NAA）,creatine（Cr）,choline compound（Cho） were analyzed. Results At least two lobes of the brain were involved in tumors with all patients.The temporal lobe,occipital lobe,corpus callosum,basal ganglia and thalamus were most involved.Iso-intensity or hypo-intensity on T1WI,hyper-intensity or mixed hyper-intensity on T2WI and FLAIR with the lesion were seen,while no prominent necrosis and calcification were founded.The area invaded by tumor showed slight swelling and no obvious space occupying effect.There were no contrast enhancement in 9 cases,irregular pathy enhancement in 2 cases,nodular enhancement in 1 case and line-like enhancement in 1 case after gadopentetate dimeglumine injection.NAA and NAA/Cr ratios decreased in some degree,while Cho,Cho/Cr and Cho/NAA levels increased in the lesion with the MRS examination. Conclusion There were significant value with MRI and MRS combining clinical information for diagnosis and differential diagnosis of gliomatosis cerebri.