目的探讨磁共振弥散张量成像 (diffusion tensor imaging DTI)在评价 足月新生儿窒息后脑损伤中的价值。方 法 搜集临床确诊为新生儿缺氧缺血性脑 病(hypoxic-ischemic encephalopathy HIE)的患儿15例，有窒息史但临床未诊断 为HIE的患儿15例及正常组新生儿15例， 应用1.5T磁共振仪对所有患儿及正常新 生儿出生后行颅脑常规序列和DTI序列 扫描。测量HIE组、窒息非HIE组及对照 组新生儿颅脑各感兴趣区的各向异性分 数(fractional anisotropy FA)值并比 较各组间FA值是否具有统计学意义。结 果 HIE组患儿额叶白质、内囊后肢、胼胝 体压部、大脑脚及半卵圆中心FA值较对 照组患儿降低，差异具有统计学意义(P ＜0.05)；窒息非HIE组患儿额叶白质、内 囊后肢、胼胝体压部及半卵圆中心FA值较 对照组新生儿降低，差异具有统计学意义 (P＜0.05)；HIE组患儿较窒息非HIE组患 儿内囊后肢FA值降低，差异具有统计学意 义(P＜0.05)。结论 磁共振弥散张量成像 可以早期发现窒息患儿脑损伤并指导临床 进行早期干预以改善预后。

Objective To determine the applied value of MR diffusion tensor imaging(DTI) in brain injury after asphyxiation in full term newborns. Methods 15 infants with HIE, 15 asphyxia infants without HIE and 15 normal infants were studied. All the neonates were examined by conventional MR imaging and diffusion tensor imaging. FA values were calculated in every regions of interest and compared between groups. Results FA values in frontal white matter、posterior limb of internal capsule、splenium of copus callosum、 cerebral peduncle、centrum semiovale of HIE infants were significantly reduced compared with control group(P＜0.05); FA values in frontal white matter、posterior limb of internal capsule、splenium of corpus callosum、centrum semiovale of asphyxia infants without HIE were significantly reduced compared with control group (P＜0.05); Only in posterior limb of internal capsule, the FA values of HIE infants were significantly reduced compared with asphyxia infants without HIE (P＜0.05). Conclusion Diffusion tensor imaging can early detect the brain injury of full term infants after asphyxiation, which may guide the clinician make the plan of treatment to improve the prognosis.