MAGNETIC RESONANCE IMAGING IN THE ASSESSMENT OF FETAL CENTRAL NERVOUS SYSTEM ANOMALIES

Abstract

Introduction: Fetal central nervous system (CNS) anomalies are among the most severe and common anomalies, with an incidence of 1: 100 to 1: 500 in newborns. Depending on the type of anomaly, the diagnosis can only be made at specifi c periods of pregnancy. The prenatal ultrasound (US) is an eff ective primary imaging modality for depicting these anomalies, and magnetic resonance imaging (MRI) is a method that provides useful confi rmation and resolves any doubts regarding the diagnosis made on prenatal ultrasound. In situations where ultrasound examination is diffi cult, fetal MRI can provide superior information owing to its many advantages. The aim of this study was to determine the importance of prenatal MRI in making an accurate diagnosis and assessment of fetal CNS anomalies after neurosonographic doubt and in detecting additional anomalies that might have been overlooked on ultrasound, which infl uences clinical decision making and anomaly outcomes. Material and methods: For this research, which was designed as a systematic review of the primary scientifi c research literature, numerous articles were used, i.e.17 scientifi c research papers, published in relevant scientifi c research online databases such as PubMed, Medline, Google Scholar, and the same were published in English in the period from 2015 to 2021. Results: From the assessment of the quality of studies with a cohort design, most studies used in this systematic review are high-quality studies (11 in total) and a smaller number are medium-quality studies (6 in total). Out of 575 cases, MRI confi rmed the ultrasound diagnosis and agreed with it in 59.8% of cases, while in 20.2% of cases, it changed the diagnosis, i.e., in 16.5%, it rejected the ultrasound diagnosis. Additional anomalies detected only on MRI occurred in 236/1225 cases, which totals 19.3% of additional anomalies. Termination of pregnancy was reported in 82/317 cases, accounting for 25.9%, while in 176 cases, the pregnancy continued. A total of 11 cases of neonatal death were reported, and the number of stillbirths or deaths after birth was reported in 8 cases. Conclusion: MRI using T2W SSFSE sequences in 3 planes, T1W and DWI in the axial plane, is a complementary modality to prenatal ultrasound in making an accurate diagnosis and assessment of CNS anomalies and detecting associated anomalies previously overlooked on ultrasound. Keywords: fetal magnetic resonance imaging, fetal neurosonography, fetal central nervous system anomalies, prenatal diagnosis.