- 1 in 10,000 births.
- One or multiple cystic lesions in the brain that communicate with the ventricles, subarachnoid space or both. The cysts are either in the fissures or in the midline.
- There are two types of porencephaly:
- Type I: unilateral, due to hemorrhage or ischemia.
- Type II: bilateral, due to neuronal migration disruption.
- Incidence of chromosomal defects is not increased.
- Structural defects: mainly ventriculomegaly.
- Detailed ultrasound examination, including neurosonography.
- TORCH test for fetal infections.
- Fetal brain MRI at ≥32 weeks’ gestation for diagnosis of grey matter heterotopias, late sulcation and migration anomalies.
- Ultrasound scans every 4 weeks to monitor the evolution of the lesion and that of ventriculomegaly.
- Standard obstetric care and delivery.
- Depends on the size and location of the lesion but neurodevelopment is often normal.
- No increased risk of recurrence.