Verification of anomalies of the central nervous system detected by prenatal ultrasound.
OBJECTIVE
The accuracy of fetal ultrasound (US) in diagnosing central nervous system (CNS) malformations was assessed with the aim to define in which cases US is reliable enough to assist in decisions on medical indication for abortions without resorting to magnetic resonance imaging (MRI).


METHODS
Retrospective analysis of the course of 69 fetuses with anomalies of the CNS detected on prenatal US in a university hospital.


METHODS
General Hospital of Vienna, University of Vienna, Austria.


METHODS
Prenatal US diagnosis was verified by postpartal US, MRI or computed tomography (CT) in the live births, and by autopsy of the fetus in cases of pregnancy termination.


RESULTS
Abortion was induced in 40 fetuses for anencephaly (n = 4), exencephaly (n = 6), dorsal dysraphism (n = 6), encephalocele (n = 3), pronounced hydrocephaly (n = 11), holoprosencephaly (n = 4), Dandy Walker cyst (n = 5), and 1 complex syndrome - all confirmed on autopsy. In 29 live births, hydrocephaly, meningomyelocele, and microcephaly had always been correctly identified prenatally. Four Chiari malformations had been missed. Agenesis of the corpus callosum had remained unnoticed in 4 out of 14 cases and been erroneously reported in 5. Diagnostic errors were frequent for Dandy-Walker cyst and great cerebellomedullary cistern.


CONCLUSIONS
Transabdominal fetal US did not lead to unjustified interventions. Inaccuracy in diagnosing abnormalities of the posterior fossa and the median telencephalon as well as aetiological clarification of hydrocephalus require additional MRI of the fetal CNS in patients selected accordingly.
Wald
M
M
Division of Neonatology and Intensive Care, Department of Pediatrics, General Hospital of Vienna, University of Vienna, Austria.
Lawrenz
K
K
Deutinger
J
J
Weninger
M
M
D001317:Austria; D002490:Central Nervous System / Q000002:abnormalities* / Q000000981:diagnostic imaging* / Q000196:embryology; D005188:False Negative Reactions; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D011247:Pregnancy; D015203:Reproducibility of Results; D012189:Retrospective Studies; D016216:Ultrasonography, Prenatal