目的：利用1.5T 核磁共振磁敏感加权成像（SWI）及扩散加权成像（DWI）对新生儿局灶性脑白质损伤中 的T1WI 高信号病灶机制进行探讨。方法：选择2012 年 月至201 年 月在我院确诊的局灶性脑白质损伤患儿 2 例，其中早产儿20 例，足月儿22 例，分别采用MR 常规序列（T1WI、T2WI、FLAIR）、DWI 及SWI 序列进行扫描， 对新生儿局灶性脑白质损伤T1WI 高信号病灶机制进行探讨。结果： 例SWI 显示中等信号，与周围信号无差别， 例患儿SWI 在双侧侧脑室后角旁发现斑片状低信号，其中早产儿1 例，足月儿 例，经卡方检验，早产儿和足月 儿PWML 在SWI 发生出血率无明显差异。50.0%(21) 的病例在DWI 上呈现高信号，早产儿组和足月儿组PWML 在 DWI 上脑白质缺氧缺血的发生率无统计学差异。 结论：大多数新生儿脑白质损伤T1WI 呈高信号病灶并不代表微出 血，T1WI 高信号产生主要与脑白质缺氧缺血、缺氧缺血- 再灌注及出血三种病理改变同时或不同阶段存在有关。

Objective To probe the machanism of SWI and DWI in T1WI high singanl of neonatal Punctate white matter lesions. Methods From June 2012 to June 2013, 42 cases with PWML dignosed by MRI in our hospital was checkted by MRI (T1WI, T2WI and FLAIR), DWI and SWI sequence can scan. We disscuss the machanism of the high signal intensity in the T1WI. Results SWI in 38 cases of displayed medium signal, and there was no difference compared with the signals around. SWI in 4 cases underwent displayed low signal, and 1 case was premature infant and 3 cases was full-term children. There was no difference between preterm infants and full term by the chi-square test. 50.0% (21 cases) showed high signal on DWI, and between preterm infants and full term group, PWML in DWI on the incidence of brain hypoxic ischemia showed no statistical difference. Conclusion The high singal of T1WI in PWML was not meaned micro bleeding in most neonatal. T1WI signal was mainly associated with brain white matter hypoxic ischemia and hypoxic、ischemic -reperfusion and bleeding from the three kinds of pathological changes at the same time or at different stages.