新型隐球菌性脑膜炎的MRI表现

MRI features of cryptococcus neoformans meningitis

目的探讨新型隐球菌性脑膜炎的MRI表现。方法本组病例10例。所有患者均接受了脑脊液墨汁涂片染色检查。9例做了MRI增强扫描。1例进行了胸部CT检查。结果MRI表现主要有4种:①2例颅脑MRI平扫未发现异常,1例增强扫描脑沟及脑池呈线状强化表现,患者常见脑基底池软脑膜受累。②5例MRI表现为以双侧基底节区为主及额、颞、顶叶等的多发斑片状或片状长T1长T2信号,增强后病变呈片状强化或未见明显强化;1例增强后基底池及桥前池亦出现软脑膜线状强化。③3例双侧大脑半球可见多发圆形或类圆形病灶,T1WI呈低信号,T2WI呈高信号,增强后呈结节状强化。④3例出现脑积水表现。结论新型隐球菌性脑膜炎误诊率高,确诊依靠病原学检查,其MRI表现虽然缺乏特异性,但对该病的早期诊断及鉴别诊断具有重要价值。

Objective To explore the features of MRI in the patients with cryptococcus neoformans meningitis （CNM）. Methods All 10 cases with CNM in this group were examined with India-ink capsule staining of CSF. 9 cases were performed with contrast enhanced MR/head scan, 1 case performed with chest CT scan. Results MRI features of CNM included： ① There were no abnormalities on MRI plain scan in 2 cases, however with linear-like enhancement in cisterns and meninges after contrast. The leptomeninges and basal cisterns were often involved. ② Multiple patch or flakelike longer T1 and T2 signals in bilateral basal ganglions, frontal, temporal and parietal lobes were displayed on MRI plain scan in 5 cases. And the lesions were enhanced like flake or no enhancement on contrast enhanced MRI. Basal and prepontine cisterns showed linear-like enhancement in 1 case. ③ Multiple round or oval shape longer T1 and T2 signals were occurred in the bilateral cerebral hemispheres, with nodular enhancement in 3 cases.④ Hydrocephalus was found in 3 cases. Conclusion CNM has high rate of misdiagnose, and the final diagnosis depend on pathology. Although MRI features of CNM lack specificity, MRI is of very important in the diagnosis and differential diagnosis of CNM.