Congenital subependymal pseudocysts: own data and meta-analysis of the literature

Congenital subependymal pseudocysts are incidental findings that are found in 0.5-5.2% of neonates during postmortem examination or head ultrasonography. In our institution we detected 10 neonates with CSEPC.

To investigate associated etiological factors, morphologic characteristics and outcome of CSEPC.

We performed a meta-analysis of the literature on CSEPC (1967-98), including our 10 cases.

A total of 256 cases of CSEPC were analyzed. Ultrasound diagnosed 77.6% of CSEPC; 48.8% were bilateral and 53.4% were located in the caudothalamic groove or head of caudate nucleus. Altogether, 93.5% resolved during 1-12 months of ultrasonographic follow-up. Compared to the general neonatal population, the following features were more prevalent in the CSEPC population: prematurity, maternal vaginal bleeding, preeclamptic toxemia, intrauterine growth restriction, asphyxia, fetal cytomegalovirus and rubella infections, congenital malformations, chromosomal aberrations, infant mortality, and neurodevelopmental handicap. The risk for neurodevelopmental handicap was significantly higher when CSEPC were associated with fetal infections, IUGR, malformations and chromosomal aberrations, or persistence of CSEPC during follow-up. CSEPC infants without any of these four conditions had a low risk for neurodevelopmental handicap.

CSEPC are morphologic features of various underlying conditions encountered in the fetus. Association of CSEPC with IUGR, fetal infections, malformations and chromosomal aberrations or persistence of CSEPC indicates a higher risk for future neurodevelopmental handicaps, probably because of the deleterious effects on the fetal brain that are inherent in these conditions. A favorable outcome is expected in the absence of these risk factors.