DWI结合常规MRI在儿童病毒性脑炎中的应用

目的 探讨DWI在儿童病毒性脑炎诊断中的价值.方法 回顾性分析36例儿童病毒性脑炎的MR表现,分析病变部位、大小、在常规MRI序列及DWI序列上的信号强度及其与发病时间的关系.结果 病变主要呈长T1长T2信号,病变主要累及大脑皮层及基底节、丘脑.36例病例中有18例DWI显示病变范围及信号强化对比优于T2WI序列,平均发病时间约8.2天;有14例T2WI序列显示优于DWI序列,发病时间约12.6天;有4例病变在DWI及T2WI序列上显示大致相仿,发病时间约7.8天.结论 常规MRI及DWI对其不同阶段的病理改变显示优势各不相同,两种检查技术互补有利于对病毒性脑炎的早期、准确诊断.

Application of DWI combined MRI for the diagnosis of viral encephalitis in children

Objective To investigate the value of diffusion weighed imaging （DWI） for the diagnosis of viral encephalitis in children.Methods The magnetic resonance （MR） findings of 36 children with viral encephalitis were retrospectively analysed.The location,size,signal intensity,as well as the time from the onset of neurologic symptoms to MR examination were studied.Results The lesions showed long T1 and long T2 signal intensities.Cerebral cortex,basal ganglia,thalamus were most frequently involved.Among the 36 cases,the lesions in 18 cases were shown clearer and more distinct on DWI than on conventional T2WI,the average time from the onset of neurologic symptoms to MR examination was 8.2 days.14 cases were shown clearer on conventional T2WI than on DWI,the average time from the onset of neurologic symptoms to MR examination was 12.6 days.4 cases were shown similarly on DWI and T2WI,the average time from the onset of neurologic symptoms to MR examination was 7.8 days.Conclusion DWI and conventional MRI have different advantages to show differrent pathological changes in different clinical stages.DWI combined with MRI has potential value in the early and precise diagnosis of viral encephalitis.