扩散加权成像在新生儿早期脑白质损伤的诊断价值

Value of Diffusion Weighted Imaging in Diagnosis of Neonatal White Matter Damage

目的:探讨磁共振扩散加权成像(diffusion-weighted imaging,DWI)在新生儿早期脑白质损伤的诊断价值。方法:选取有明确围生期窒息史,日龄≤7天的早产儿缺氧缺血性脑损伤(HIBD)412例、足月新生儿缺氧缺血性脑病(HIE)566例作为研究对象,另随机选取日龄相同临床及颅脑MRI检查结果正常的156例早产儿、227例足月新生儿作为正常对照组,全部行颅脑常规MRI和DWI检查。分别测量DWI上研究组异常高信号区和正常对照组同一位置表观弥散系数(ADC值)。将两组ADC值分别计算其平均值±标准差,组间数据分别进行t检验分析,P值小于0.05表明有统计学意义。结果:①412例HIBD中382例常规MRI显示脑室旁短T1信号。156例DWI表现为脑室旁、内囊前后肢、胼胝体膝压部有异常高信号占37.86%,病灶呈局灶性分布74例,弥漫性分布82例,其中30例常规MRI未见异常但在DWI显示异常;566例HIE中,轻度267例、中度206例、重度93例。DWI上表现为皮质下深部白质异常高信号为227例,病变显示率为40.1%,异常高信号呈局灶性分布150例,弥漫性分布77例,其中18例在常规MRI未见异常。②DWI上,HIBD灶状病变和弥漫性病变平均ADC值分别为(0.976±0.041)×10-3mm2/s,(0.949±0.039)×10-3mm2/s;HIE灶状病变和弥漫性病变平均ADC值分别为(0.639±0.108)×10-3mm2/s,(0.626±0.112)×10-3mm2/s,研究组脑白质异常高信号区平均ADC值分别显著低于正常对照组同一部位,P<0.05,表明ADC值研究组与正常对照组组间存在差异。结论:常规MRI检查与DWI序列结合可显著提高新生儿脑白质损伤的早期诊断率,为临床早期准确诊断脑瘫、早期干预、评估预后及康复治疗奠定基础。

Purpose：To discuss the value of diffusion weighted imaging（DWI）in the early diagnosis of neonatal white matter damage.Methods：Four hundred and twelve premature children,566 full-term newborns with perinatal asphyxia and 383 age-matched normal controls were recruited.All children were examined by conventional magnetic resonance imaging and DWI.The ADC values of abnormal high signal area in the study group and at the same location of the control group were measured respectively.All data were analyzed with a two-tailed student t test.Results：① In 412 HIBD cases,382 cases showed high signal on T1WI in periventricular.One hundred and fifty-six cases showed abnormal high signal on the DWI in periventricular,anterior/posterior limb of internal capsule,genu of corpus callosum and spleniumof corpus callosum.Seventy-four cases showed focal lesions.Eighty-two cases showed diffuse lesions.Thirty cases showed nomal on MRI but abnomal on DWI.In 566 HIE cases,267 cases showed mild,206 cases showed moderate,93 cases showed severe.Two hendred and twenty-seven cases of 566 HIE showed abnormal high signal in subcortical white matter on DWI,150 cases showed of focal abnormal high signal on DWI,77 cases showed diffuse abnormal high signal on DWI,18 cases showed nomal on MRI.②The mean ADC values for focal,diffuse lesions of HIBD and HIE were 0.976±0.041 ×10-3mm2/s,0.949±0.039 ×10-3mm2/s,0.639±0.108×10-3mm2/s,0.626±0.112×10-3mm2/s,respectively,which were lower than those of control group,1.261±0.069 ×10-3mm2/s,1.246±0.106 ×10-3mm2/s,0.931±0.025 ×10-3mm2/s,0.943±0.107 ×10-3mm2/s,respectively.ADC values on DWI were compared between the patients and the controls,the difference showed statistically significant,P0.05.Conclusion：Conventional MRI combined with DWI can significantly improve the early diagnosis rate of neonatal white matter damage.It is helpful for early accurate diagnosis,early intervention,assessment and active rehabilitation prognosis of cerebral palsy for clinical.