磁共振成像表观扩散系数变化对新生儿化脓性脑膜炎脑损伤纵向评估

Longitudinal evaluation of MR ADC for brain injury in neonatal purulent meningitis

背景既往尚无新生儿化脓性脑膜炎在不同颅脑并发症下ADC值的纵向变化研究。目的回顾性总结新生儿化脓性脑膜炎在发病后不同病程阶段的头颅MR表现,在髓鞘化过程中分析不同颅脑并发症下脑组织ADC值随病程的变化规律。设计病例对照研究。方法以足月新生儿化脓性脑膜炎并行头颅MR检查者为病例组,基于颅脑并发症中有无脑实质损伤灶和脑积水分为病例1组(无脑实质损伤灶和脑积水)、病例2组(有脑实质损伤灶,无脑积水)、病例3组(有脑积水无脑实质损伤灶)和病例4组(有脑实质损伤灶和脑积水)。以发病至头颅MR检查间隔时间0~7 d、~28 d、~60 d和~120 d分为病程A~D组;根据MR检查时患儿日龄,病程A组分为A1组(0~14 d)和A2组(~28 d),病程B组分为B1组(~28 d)和B2组(~60 d)。与病例组同期因其他疾病在同院行常规头颅MR且未观察到异常病变的儿童为对照组。主要结局指标相同日龄或相同病程下MR评估新生儿化脓性脑膜炎脑实质ADC值变化趋势。结果173例新生儿化脓性脑膜炎进入本文分析,病例组MR检查302例次,病程A~D组有241例次MR检查的ADC值进入本文分析;对照组20例。随着日龄的增加,对照组和病例组ADC值均呈降低趋势。不同病程(相同日龄)比较结果中,大脑皮层、深部白质在各个病程中,病例1~3组和对照组ADC值差异均无统计学意义(胼胝体压部的部分病程除外);皮层下白质在病程0~60 d中,病例2和3组ADC值明显低于对照组,病例3组及部分病程中病例2组ADC值明显低于病例1组,皮层下白质在病程61~120 d中,病例2、3组和对照组ADC值差异无统计学意义,病例1组(除外顶叶白质)ADC值明显高于对照组;深部灰质核团在病程0~30 d中,病例1~3组ADC值明显低于对照组,在病程31~120 d中,病例1~3组和对照组ADC值差异均无统计学意义。结论在新生儿化脓性脑膜炎患儿,皮层下白质在病程1~2个月ADC值降低,病程3~4个月时ADC值正常或升高,提示髓鞘化进程受阻;深部灰质核团ADC值在病程1个月内降低,而病程2~4个月时恢复正常。MR DWI定量ADC值有助于对无脑结构损伤的新生儿脑膜炎微观损伤的评估。

Background There have been no longitudinal studies of ADC values under different intracranial complications of neonatal purulent meningitis.Objective To retrospectively summarize the cranial MR of neonatal purulent meningitis in different course of disease,and analyze the variation characteristics of ADC value in brain tissue with different course of disease and its relationship with myelination process under different intracranial complications.Design A case-control study.Methods Full-term neonates who had purulent meningitis and cranial MR were taken as the case group and divided into 4 case groups according to intracranial complications--case group 1 of cerebral parenchymal lesions(-)and hydrocephalus(-),case group 2 of cerebral parenchymal lesions(+)and hydrocephalus(-),case group 3 of cerebral parenchymal lesions(-)and hydrocephalus(+)and case group 4 of cerebral parenchymal lesions(+)and hydrocephalus(+).According to the interval between onset time and MR,disease course was divided into 0-7 days,-28 days,-60 days and-120 days,which were named as group A to D respectively.According to the age at the time of taking MR,course A was divided into course A1(0-14 days)and course A2(-28 days),and course B was divided into course B1(-28 days)and course B2(-60 days),and 20 normal infants were included in each group as the control group.Main outcome measures Trends of ADC value in brain parenchyma of patients with neonatal purulent meningitis evaluated by MR at the same age or course of disease.Results Totally 173 cases of neonatal purulent meningitis met the inclusion criteria of the case group.The maximum age and course of this study was 120 days.Therefore,MR examinations in the case group were 302 times.The ADC values of 241 MR in course A~D were analyzed in different case groups.The ADC values of the control group and the case group decreased with the increase of age.In the comparison of results of different course of disease(with the same age),there was no statistical significance in the ADC values of cerebral cortex and deep white matter in different course of disease,except for part of the course of splenium of corpus callosum.During the course of 0-60 days,the ADC value of subcortical white matter in case 2 and 3 groups was significantly lower than that in control group,and the ADC value of subcortical white matter in case 3 group and part of the course of case 2 group was significantly lower than that in case 1 group.During the course of 61-120 days,the ADC values of subcortical white matter in case 2 and 3 groups were not significantly different from those in control group,while the ADC values of subcortical white matter(except parietal white matter)in case 1 group were significantly higher than those in control group.During the course of disease 0-30 days,the deep gray matter ADC value in case 1,2 and 3 groups was significantly lower than that of the control group.During the course of disease 31-120 days,the deep gray matter ADC value in case 1,2 and 3 groups was not significantly different from that of the control group.Conclusion In patients with neonatal purulent meningitis,subcortical white matter showed decreased ADC values within 1-2 months of the course of disease,and normal or increased ADC values at 3-4 months of the course of the disease,which suggested that the process of myelination was affected.Deep gray matter showed decreased ADC values within 1 month,and normal ADC values at 2-4 months of the course of the disease.MR DWI quantitative ADC is helpful to evaluate the micro injury of neonatal meningitis without brain parenchymal structure injury.