Prenatal Evaluation, Imaging Features, and Neurodevelopmental Outcome of Prenatally Diagnosed Periventricular Pseudocysts

Abstract

Background and purpose: Periventricular pseudocysts are cystic cavities that lack the ependymal cell lining found in true cysts. The aim of this study was to characterize periventricular pseudocysts and related findings and their neurodevelopmental outcome.

Materials and methods: This was a retrospective study of periventricular pseudocysts detected prenatally on fetal MR imaging in 26 fetuses. The fetuses were divided into group A (n = 8), which included cases with isolated periventricular pseudocysts, and group B (n = 18), which included cases of periventricular pseudocysts with additional findings. Cases were further subdivided into connatal cysts and subependymal pseudocysts. Data collected included prenatal history, MR imaging features, sonographic follow-up, and neurodevelopmental outcome.

Results: All cases in group A (n = 8) had a normal outcome. In group B (n = 18), 6 pregnancies were terminated and 2 had an abnormal outcome. Both cases with an abnormal outcome involved patients with subependymal pseudocysts. No significant association was found between the morphologic features on MR imaging and the neurodevelopmental outcome.

Conclusions: Neurodevelopmental outcome in cases of isolated periventricular pseudocysts detected prenatally appears to be normal. A detailed evaluation should be performed to rule out additional brain findings, chromosomal aberration, and fetal malformation. This evaluation should include the following: maternal TORCH status, detailed fetal sonographic anatomic evaluation, fetal echocardiogram, fetal brain MR imaging, amniocentesis and karyotyping/comparative genomic hybridization, and genetic counseling. Additional findings on MR imaging, including mild-to-moderate dilated ventricles, asymmetric ventricles, or T2 hyperintense signal in the white matter without other findings or major fetal abnormality, appear to be benign. Connatal cysts appear to be benign.

Fig 1.

A, Schematic representation of the differential diagnosis between periventricular pseudocysts and periventricular leukomalacia. Originally published by Malinger et al. B, Differential diagnosis between the cystic lesions seen in periventricular leukomalacia (PVL), connatal cysts (CC), and subependymal cysts (SC). Malinger et al original publication modified by Epelman et al.

Fig 2.

Flowchart illustrating the study design and outcome. Cases are divided to 2 groups: fetuses in group A had only PVPC on MR imaging, while fetuses on group B had additional findings on MR imaging or fetal abnormality. Fetal abnormality is defined as the presence of fetal infection, chromosomal abnormality, IUGR, abnormal echocardiogram findings, or other fetal malformation. The groups were further subdivided into connatal cysts or subependymal pseudocysts.

Fig 3.

T2 MR imaging coronal view. A, Case 5, bilateral connatal cysts located at the external angle, anterior to the foramina of Monro. B, Case 17, bilateral subependymal pseudocysts located posterior to the foramina of Monro.