小儿流行性乙型脑炎磁共振波谱特征及随访研究

目的：探讨磁共振氢质子波谱（1H-MRS）对小儿流行性乙型脑炎预后评价的价值。方法：对17例常规MRI有信号异常的乙脑患儿行1H-MRS扫描,并选择15例同龄健康志愿者对照。病例组在3个月内进行随访并复查MRI,根据随访结果将患者分治愈组和未治愈组,回顾性分析两组患儿首次1H-MRS特征。结果：病灶在T1WI呈斑片状等或稍低信号、T2WI及FLAIR呈稍高或高信号,其中累及灰质核团13例,均呈对称性分布,边界清晰。17例患儿中1H-MRS均见不同高度Lac峰,7例NAA峰有明显下降,2例Cho峰轻度降低,1例出现Cr峰下降,3例出现MI峰。病例组与对照组之间NAA/（Cr＋Cho）值差异有显著性意义（t=5.98,P〈0.05）。根据随访结果,治愈组11例,未治愈组6例,两组NAA/（Cho＋Cr）差异有显著性意义（t=3.45,P〈0.05）。结论：乙脑患儿病变易累及灰质核团,1H-MRS多见Lac双峰,NAA明显下降往往提示患儿病情较重,预后不良。1H-MRS能反映乙脑严重程度并判断预后,是常规MRI有益补充。

Study of Japanese encephalitis in children with magnetic resonance spectroscopy

Objective：To Investigate the value of proton magnetic resonance spectroscopy （1H-MRS） in pediatric Japanese encephalitis （JE）.Methods：Conventional MRI and 1H-MRS scanning were performed in 17 JE and in 15 healthy age-matched controls.All study cases received follow-ups in the next three months,then they were divided into two groups according to whether being cured or not.Results：There was a wide range of brain inflammation in most lesions,and the basal ganglia-the hypothalamus thalami were the most frequently involved areas.Out of 17 cases with 1H-MRS,14 had elevated Lac peaks,7 had obviously decreased NAA peaks,2 had mildly decreased Cho peaks,1 showed dropped Cr peak,3 had elevated MI peaks.There was a significant decrease in the ratio of NAA/（Cr＋Cho） in the study group compared with the control group （t=5.98,P0.05）.According to the followups,11 were cured out of 17 cases,the ratio of NAA/（Cr＋Cho） in the cured group had a significant decrease compared with that of non-cured group （t=3.45,P0.05）.Conclusion：JE often shows characteristic basal ganglia-the hypothalamus thalami involvement,the 1H-MRS features of JE in children usually includes elevated Lac peak and decreased NAA peak.Obviously decreased NAA peak means that the lesion is prompted to poor prognosis,which can reflect the severity and prognosis of Japanese encephalitis.