RESUMO
Objective:To explore the value of prenatal MRI in the diagnosis of isolated mild and moderate bilateral ventriculomegaly and neural development of the fetuses after birth.Methods:This is a retrospective study involving 244 singleton fetuses with isolated mild or moderate lateral ventriculomegaly diagnosed by both prenatal ultrasound and MRI in Huzhou Maternity & Child Health Care from May 2013 to June 2017, consisting of 82 cases with bilateral ventriculomegaly (BVM) and 162 with unilateral ventriculomegaly (UVM). The two groups were further divided into two subgroups: mild (lateral ventricle width: 10.0-12.0 mm, bilateral 56 cases, unilateral 120 cases) and moderate group (lateral ventricle width: >12.0-<15.0 mm, bilateral 26 cases, unilateral 42 cases). In addition, 50 singleton fetuses without any abnormality in the nervous system in prenatal check were included in the control group during the same period. All neonates were reexamined by ultrasound within one week after birth, and followed up regularly at the age of 3, 6, 12 and 18 months. Gesell Development Schedules (GDS) were used to evaluate the central nervous system's function, and postnatal changes in lateral ventriculomegaly were observed. Statistical analysis was performed by t, F, Chi-square tests (or Fisher's exact test). Results:(1) There was no difference among intervals between MRI scan and delivery in the BVM, UVM, and the control groups. The disappearance rate of lateral ventriculomegaly after birth was 80.4% (45/56) in the mild BVM group, 42.3% (11/26) in the moderate BVM group, 88.3% (106/120) in the mild UVM group, and 57.1% (24/42) in the moderate UVM group ( χ2=35.183, P<0.001). (2) The GDS evaluation results in the BVM group at 6, 12, and 18 months after birth were worse than those in the UVM group (all P<0.0167). The GDS evaluation results in the BVM group were worse than those in the control group at 3 and 6 months after birth [3 months: normal: 58.5% (48/82) vs 86.0% (43/50), borderline: 22.0% (18/82) vs 10.0% (5/50), delay: 19.5% (16/82) vs 4.0% (2/50), χ2=11.425; 6 months: normal: 63.4% (52/82) vs 88.0% (44/50), borderline: 19.5% (16/82) vs 8.0% (4/50), delay: 17.1% (14/82) vs 4.0% (2/50), χ2=9.678; all P<0.0167]. (3) The GDS evaluation results in the moderate BVM group at 6, 12, and 18 months after birth were worse than those in the moderate UVM group [6 months: normal: 30.8% (8/26) vs 69.0% (29/42), borderline: 30.8% (8/26) vs 21.4% (9/42), delay: 38.5% (10/26) vs 9.5% (4/42), χ2=11.417; 12 months: normal: 53.8% (14/26) vs 88.1% (37/42), borderline: 23.1% (6/26) vs 9.5% (4/42), delay: 23.1% (6/26) vs 2.4% (1/42), χ2=11.199; 18 months: normal: 65.4% (17/26) vs 95.2% (40/42), borderline: 15.4% (4/26) vs 2.4% (1/42), delay: 19.2% (5/26) vs 2.4% (1/42), χ2=10.568; all P<0.0167]. The GDS evaluation results of the moderate BVM group at 3, 6, 12, and 18 months after birth were worse than the control group. (4) In the BVM group, the GDS scores at 18 months of age were better than those at three months of age ( χ2=8.224, P=0.016). Conclusions:(1) Most mild BVM would disappear spontaneously after birth, while more in mild UVM cases. (2) The postnatal GDS evaluation results of the BVM group is significantly worse than that of the UBM group at months of age; (3) Fetuses with less severe isolated BVM are more likely to have improved GDS score after birth.