脊柱裂胎儿小脑延髓池改变的超声研究

Study on the changes of cisterna magna in fetus with spina bifida by ultrasonography

目的探讨超声检测胎儿小脑延髓池(CM)前后径对提示脊柱裂诊断的价值。方法胎儿脊柱裂36例,对照组为相应孕周的108例正常胎儿。经小脑横切面观察胎儿小脑形态、结构,并测量CM前后径。结果36例脊柱裂胎儿,囊性脊柱裂33例,隐性脊柱裂3例。21～36孕周胎儿34例,声像图表现为CM消失;16～20孕周胎儿2例,声像图表现为CM缩小。对照组108例胎儿,6例CM缩小,无CM消失。脊柱裂胎儿CM消失的发生率高于对照组(P<0.05)。结论孕21周以后胎儿,CM消失是胎儿脊柱裂超声检查重要的间接征象。

Objective To explore the value of cistema magna （CM） anteroposterior diameter measured by uhrasonography in diagnosis of spina bitida in fetus. Methods Thirty-six fetus with spina bifida and 108 normal fetus from 16 to 36 gestational weeks were enrolled in this study. The morphous and structure of fetal cerebellum were observed through cerebellar transverse plane,then the anteroposterior diameter of CM was measured. Results In 36 fetus of spina bifida,there were 33 cases of spina bifida cystica and 3 cases of spina bifida occulta. The ultrasonic appearance of CM disappeared in 34 fetus （ 21 to 36 gestational weeks） ,and decreased in two fetus （ 16 to 20 gestational weeks）. In 108 fetus of control group,CM decreased in 6 cases,no CM disappeared. The incidence of CM disappearance in spina bifida fetus group was higher than that in control group. Conclusion CM disappearance is an important indirect sign in diagnosis of fetal spina bifida after 21 gestational weeks.