儿童病毒性脑炎的MRI表现与病原学检测对照分析

Comparative analysis of MRI and pathogen detection of viral encephalitis in children

目的:分析儿童病毒性脑炎的MRI表现、临床特征及病原检测结果,以期通过影像学表现预测病原学感染类型、早期指导临床治疗。方法:回顾性分析经临床明确诊断的42例病毒性脑炎的MRI表现和临床资料,对照分析影像征象与病原检测结果。结果:42例中,手足口病脑炎12例,单纯疱疹病毒脑炎10例,支原体脑炎1例,EB病毒脑炎4例,流行性乙型脑炎4例,流感病毒脑炎8例,抗N-甲基-D-天冬氨酸受体脑炎(NMDAR)3例。血乳酸升高32例,脑脊液乳酸脱氢酶(LDH)升高35例。42例均表现为病灶T1WI呈稍低信号、T2WI呈高信号、DWI呈高信号、ADC图呈低信号,增强扫描未见强化;4例脑膜强化;5例MRS示病灶出现乳酸峰;2例ASL序列见灌注减低,MRA示一侧大脑中动脉部分分支闭塞。临床表现重者深部灰质核团、脑干、脊髓异常信号,部分类型病毒脑炎MRI表现有特征性。结论:儿童病毒性脑炎易出现高乳酸血症,影像鉴别诊断应重视使用fMRI技术,双侧对称性病变需与遗传代谢脑病鉴别,MRI特征表现对病原学诊断及预后评估有指导价值。

Objective:To analyze the MRI,clinical features and pathogen detection results of viral encephalitis in children,and to expect to guide the clinical treatment by predicting the type of pathogenic infection in the early stage.Methods:The MRI images and clinical data of 42 cases of viral encephalitis diagnosed clinically were analyzed retrospectively,and compared with the results of image features and pathogen detection.Results:There were 12 cases of encephalitis caused by hand-foot-mouse disease,10 cases of herpes simplex encephalitis,1 case of mycoplasma encephalitis,4 cases of EB encephalitis,4 cases of epidemic encephalitis B,8 cases of influenza virus encephalitis,and 3 cases of anti-N-methyl-D-aspartic acid receptor encephalitis(NMDAR).There were 32 patients with increased blood lactic acid and 35 patients with increased cerebrospinal fluid LDH.42 lesions showed low signal in T1WI,high signal in T2WI,high signal in DWI and low signal in ADC map,and no enhancement was observed.However,4 patients presented meningeal enhancement.Lactic acid peak was observed in 5 patients with MRS,decreased perfusion in 2 patients with ASL sequence,and partial branch occlusion of unilateral middle cerebral artery on MRA.The clinical manifestations were the abnormal signals of deep gray matter nuclei,brainstem and spinal cord,and the MRI images of some types of viral encephalitis were characteristic.Conclusions:Children with viral encephalitis are prone to hyperlactic acid,so the application of the technology of fMRI should be taken seriously in the identified diagnosis of imaging,which shows that bilateral symmetrical lesions need to be distinguished from hereditary metabolic encephalopathy,MRI image features have the guiding value in the diagnosis and prognosis of pathogens.