胎儿Joubert综合征及相关疾病MRI表现

MRI manifestations of fetal Joubert syndrome and related disorders

目的探讨产前MRI诊断胎儿Joubert综合征及相关疾病(JSRD)的价值。方法回顾性分析5胎JSRD胎儿产前MRI资料,并于MRI中脑轴位层面分别测量冠根比、峡池比及第四脑室顶部左右径和前后径比。结果 5胎产前MRI中脑轴位层面均可见"臼齿"征(MTS),小脑蚓部缺失,表现为"狭缝"征;其中3胎伴枕大池增宽。5胎冠根比为0.58~0.90,峡池比0.84~1.00,第四脑室顶部横径和前后径比0.42~0.60。结论 "臼齿征"和"狭缝"征为JSRD特征性MRI表现,有助于产前诊断胎儿JSRD。

Objective To explore the diagnostic value of prenatal MRI in fetal Joubert syndrome and related disorders （JSRD）. Methods Prenatal MRI data of 5 JSRD fetuses were analyzed retrospectively. The ratio of AP diameters of crown to root of molar tooth sign, the ratio of AP diameters of isthmus to interpeduncular fossa, and the ratio of the transverse to AP diameters of the roof of the fourth ventricle on the axial images of the midbrain were measured. Results Molar tooth signs were observed in 5 fetuses on the axial images of midbrain, The cerebellar vermis disappeared, and cleft sign was observed. Enlarged cisterna magna was observed in 3 fetuses. The ratios of AP diameters of crown to root were 0. 58-0. 90 , of AP diameters of isthmus to interpcduncular fossa were 0. 84-1. 00 , and of transverse to AP diameters of the fourth ventricle roof were 0. 42-0. 60. Conclusion Molar tooth sign and cleft sign were characteristic findings for JSRD on MRI, therefore being helpful to prenatal diagnosis of JSRD.