CHOROID-PLEXUS VENTRICULAR WALL SEPARATION IN FETUSES WITH NORMAL-SIZED CEREBRAL-VENTRICLES AT SONOGRAPHY - POSTNATAL OUTCOME

OBJECTIVE. The choroid plexus typically fills the atrium of the latera l ventricles of the brain in normal fetuses, but separates from the me dial ventricular wall with increasing ventriculomegaly. Sonographic de piction of choroid plexus-ventricular wall separation has been associa ted with a high frequency of unfavorable outcomes in fetuses with mild ventricular dilatation. This separation, however, is also observed in a small subgroup of fetuses with normal ventricular measurements. The objective of this study was to ascertain the prognosis for fetuses wh en choroid plexus-ventricular wall separation and normal-sized lateral ventricles are seen on antenatal sonograms. MATERIALS AND METHODS. Po stnatal follow-up was reviewed for 74 fetuses showing a 3 mm or greate r separation between the choroid plexus and the medial ventricular wal l and normal-sized (less than or equal to 10 mm) ventricles on antenat al sonograms. Fetuses were divided into normal and abnormal outcome gr oups, and the data were analyzed to determine if the amount of separat ion, the ventricular atrial diameter, or the evolution of these findin gs on follow-up sonograms was predictive of outcome. RESULTS. Fifty-ni ne patients (80%) had normal outcomes (defined as no congenital anomal ies and no significant subsequent medical history apart from usual inf ant and childhood illnesses) and 15 patients (20%) had abnormal outcom es. The severity of the abnormalities varied widely ranging from relat ively inconsequential, such as isolated polydactyly, to complex congen ital malformation syndromes resulting in neonatal death. No consistent pattern of malformation was evident. Although we found a statisticall y significant difference in the degree of choroid plexus-ventricular w all separation when fetuses were separated into normal and abnormal ou tcome groups, the range of measurements obtained in these two populati ons overlapped considerably. Outcomes were normal in all 13 patients i n whom the choroid plexus-ventricular wall separation had returned to normal by the time of the last antenatal sonogram. CONCLUSION. A separ ation of 3 mm or greater between the choroid plexus and the medial ven tricular wall is an important finding that is associated with an incre ased risk of an abnormal outcome even in the subpopulation of fetuses with normal-sized ventricles. Although the outcome will be normal in t he majority (80%) of such fetuses, identification of choroid plexus-ve ntricular wall separation mandates a meticulous examination of fetal a natomy.