[Correlation between fetal borderline ventriculomegaly and chromosomal abnormalities]

Objective: To assess the association between fetal borderline ventriculomegaly (VM) diagnosed by prenatal ultrasound and chromosomal abnormality. Methods: Sonographic manifestation and chromosome of 129 cases with borderline VM diagnosed by prenatal sonography were analyzed retrospectively. All subjects were divided into 3 groups, 80 cases (62.0%, 80/129) in isolated VM (IVM) group, 27 cases (20.9%, 27/129) of VM with no additional structural abnormality group (including ultrasonic soft marker, abnormal volume of amniotic fluid and fetal growth restriction) and 22 cases (17.1%, 22/129) of VM with structural abnormality. Furthermore, the IVM group was sub-grouped according to fetal sex, lesion position and degree of expansion. The results of chromosome detection in different sub-group were analyzed statistically. Results: (1) Overall situation: in 129 enrolled cases of borderline VM, 8 cases of chromosomal abnormality were detected by CMA and the positive detection rate was 6.2% (8/129) , of which 2 cases were abnormal karyotype and 6 cases were pathologic copy number variation (p-CNV) . (2) The results of fetal chromosomal abnormalities detected in 3 groups: there were no case of abnormal karyotype and 4 cases of p-CNV in IVM group, the detection rate of chromosome abnormalities was 5.0% (4/80) . One case of abnormal karyotype and 2 cases of p-CNV in VM with no additional structural abnormality group, the detection rate was 11.1% (3/27) . One case of abnormal karyotype and no case of p-CNV in VM with structural abnormality group, the detection rate was 4.5% (1/22) . There were no significant difference among 3 groups (all P>0.05) . Conclusions: The risk of chromosomal abnormaliy increases in fetus with borderline VM. When the fetal VM is found by ultrasound, it is necessary to perform comprehensive scanning and regular follow-up. Fetal chromosomes examination is recommended.