Abstract: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.