- 1 in 50 fetuses at 20 weeks’ gestation.
- More than 90% resolve by 26 weeks.
- Single or multiple cystic areas (>2 mm in diameter) in one or both choroid plexuses of the lateral cerebral ventricles.
- Associated with increased risk for trisomy 18 and possibly trisomy 21.
- Detailed ultrasound examination for presence of other markers of trisomies 18 and 21. In the absence of other markers there is no need for invasive testing.
- Follow-up should be standard.
- Standard obstetric care and delivery.
- Isolated: no increased risk of recurrence.
- Part of trisomies: 1%.