MRI在新生儿化脓性脑膜炎中的应用

Application of MRI in neonatal purulent meningitis

新生儿化脓性脑膜炎（化脑）是指出生4周内由化脓菌引起的脑膜炎症，幸存者40％～50％可留下失听、失明、癫痫、脑积水、智力和（或）运动障碍等后遗症。由于新生儿化脑的症状往往不典型，加上不规范的应用抗生素，以及少数处于病程早期患儿已有临床表现但是脑脊液还没有明显变化的患者，可能造成脑脊液的改变亦不典型，从而给早期诊断带来一定困难。目前有关预后及脑损害的报道多是颅脑计算机断层扫描（ CT）检查，尽管CT能显示脑膜炎但对微小病变不敏感，且CT的发射方式可造成电离辐射的存在，儿童CT检查更能导致寿命辐射风险度的显著上升。近年来，磁共振成像（ MRI ）特别是弥散加权成像（ DWI）已成为评估早期新生儿脑损伤的重要手段之一。

Neonatal purulent meningitis （ PM） is caused by pyogenic bacteria within 4 weeks after birth , and 40%-50%of survivors will suffer from sequela such as hearing loss , blindness, epilepsy, hydrocephalus, intelligence and （or） movement disorders.The symptoms of neonatal PM are not typical , and antibiotics are not used according to standard .A few neonates at early stage have clinical manifestations but without obvious change in cerebrospinal fluid .All of these factors bring difficulties for early diagnosis of PM .CT is the examination method in most of the reports on prognosis and brain damage at present .Although CT can show meningitis , it is not sensitive to minimal lesion.Meanwhile, emission of CT may cause ionizing radiation .Infants taking CT examination can result in significant rise in radiation risk of life expectancy .In recent years , MRI, especially DWI has become one of the important means for early assessment of neonatal brain injury.