MRI evaluation of fetal tethered-cord syndrome: correlation with ultrasound findings and clinical follow-up after birth

Abstract

The study aimed to describe the features of magnetic resonance imaging (MRI) in fetuses with tethered-cord syndrome (TCS) or lower spinal cord (LSC) and to analyse the clinical outcomes and complications during follow-up. This is a retrospective study of fetuses diagnosed with TCS or LSC using MRI from January 2015 to August 2019. The average gestational week (GW) at MRI examination was 25.46±4.73 GW (range: 21-39 GW). MRI was used1 to identify the anatomical landmarks of the spine2; to measure the width of the conus medullaris and record the ending position of the LSC3; and to analyse other neurological deformities. The diagnostic results between MRI and ultrasonography (US) were compared. A total of 38 fetuses with suspected intracranial or spinal lesions on US or MRI were included. Among all fetuses, 17 fetuses were diagnosed with LSC or TCS without associated anomalies. Twenty-one fetuses had complications of central nervous system (CNS) anomalies, one fetus also had a diagram hernia, and one fetus had an inverse foot. MRI provided more diagnoses than US in nine fetuses. Two cases of diastematomyelia detected on MRI were missed on US. The capability of MRI was comparable with that of US in terms of displaying spina bifida. In the present study, fetal MRI showed better performance than US for depicting TCS and related CNS abnormalities. MRI provided clinicians with additional information in terms of prenatal counselling and management.