Prenatal diagnosis of central nervous system abnormalities: Neurosonography versus fetal magnetic resonance imaging

Abstract

ObjectiveTo share our experience in diagnosis of congenital central nervous system (CNS) abnormalities by fetal magnetic resonance imaging (MRI). Study designThis study consisted of 110 pregnancies. Neurosonography (NS) findings were compared with MRI results. Anomalies were categorized into 10 groups: 1) Corpus callosum (CC) and cavum septum pellucidum (CSP) anomalies, 2) Neural tube defects (NTD), 3) Posterior fossa anomalies (PFA), 4) Primary ventriculomegaly (PVM), 5) Microcephaly, 6) Macrocephaly, 7) Periventricular leukomalacia (PVL), 8) Craniosynostosis, 9) Intracranial hemorrhage (ICH) and 10) Lumbosacral teratoma. Demographic features, clinical characteristics and perinatal outcomes of the study subjects were evaluated. ResultsGestational weeks for NS and for MRI were 25.5 and 26.5 weeks, respectively. Fourteen (12.7%) pregnancies were terminated. PVM (n = 36, 32.7%), CC and CSP anomalies (n = 29, 26.3%), PFA (n = 11, 10%) and NTD (n = 11, 10%) were the most common fetal MRI indications. There were no statistically significant differences between the accuracy of fetal NS and fetal MRI for CC and CSP anomalies, NTDs, PFA and PVM (p = 0.09, 0.43, 0.45 and 0.23, respectively). However, fetal MRI was more accurate for the detection of normal anatomic findings in cases with suspected microcephaly, macrocephaly and craniosynostosis in NS when pooled together (p = 0.007). Furthermore, MRI also seemed to be advantageous in CC & CSP anomalies though it was not validated by statistical measures. No statistically significant difference was found for diagnostic performance of NS and MRI according to gestational week (p = 0.27). ConclusionFetal MRI in addition to NS may improve diagnostic accuracy in pregnancies with congenital CNS abnormalities.