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Objective To demonstrate that MRI is more advantageous than ultrasound in the detection of ischemic cerebral lesions precisely in twin-twin transfusion syndrome(TTTS)fetus following fetoscopic selective laser coagulation(SLCPV).Methods The fetus with TTTS treated by SLCPV were collected.All fetuses underwent brain MRI within 1-5 days after the procedure and a follow-up MRI at 29-32 weeks'gestation.All fetuses also had frequent ultrasound evaluation until delivery.Results Twenty-five pregnancies with TTTS were included in the study.Six pregnancies resulted in survival of only one twin after the procedure(Group A),while the other 19 pregnancies resulted in the survival of both twins(Group B),as assessed at the time of initial MRI.Two fetus in Group A and three in Group B had evidence of bleeding in lateral ventricle.Two fetus in Group B had actue brain ischemia.One fetus in Group B had appeared brain atrophy and choosed to terminate pregnancy.Conclusion MRI can make a clearer diagnosis of cerebral damage of TTTS fetus in a short period after SLCPV.
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Objective To measure middle cerebral artery (MCA) hemodynamic parameters of chronic cerebral ischemia in middle aged and elderly people with phase contrast magnetic resonance imaging (PCMRI),and to explore cerebral blood flow dynamic pattern in different degrees of chronic cerebral ischemia patients.Methods Middle aged and elderly people underwent conventional MRI scan,and were divided into 12 cases of the normal group,16 cases of mild cerebral ischemia group and 13 cases of obvious cerebral ischemia group.All groups underwent bilateral MCA PCMRI.Bilateral MCA hemodynamic parameters and phase-velocity curve in a heartbeat cycle were obtained by QFLOW analysis software on the workstation for post-processing.Bilateral MCA vascular area,peak velocity (PV),mean velocity (MV) and mean flow (MF) were recorded.The differences of bilateral MCA hemodynamic parameters among the three groups were compared by SPSS17.0 software.Results Bilateral MCA vascular area,MV,MF and right MCA PV among three groups were statistically significant by one-Way ANOVA (P＜0.05).Compared with normal group,systolic peak of bilateral MCA phase-velocity curve was low,dull,widen,and the connection between the diastolic peak and systolic peak became flattened in chronic cerebral ischemia patients.Conclusion PCMRI can reflect the differences of the cerebral blood flow dynamic change pattern between different degrees of chronic cerebral ischemia.