Additional value of advanced neurosonography and magnetic resonance imaging in fetuses at risk for brain damage

Abstract

Objective: To assess the additional value of fetal multiplanar (axial, coronal and sagittal) neurosonography and magnetic resonance imaging (MRI) to that of the standard axial ultrasound planes in diagnosing brain damage in fetuses at high risk. Methods: This was a prospective, multicenter, observational study. Women were eligible for participation if their fetus was at risk for acquired brain anomalies. Risk factors were congenital infection, alloimmune thrombocytopenia, fetal growth restriction, trauma during pregnancy, fetal hydrops, monochorionic twins and prior ultrasound finding suggestive of an acquired brain anomaly. Examinations of the fetal brain before birth comprised axial ultrasound and advanced neurosonography biweekly and MRI once. After birth, neonatal cranial ultrasound was performed at < 24 h and at term-equivalent age. Neonatal brain MRI was performed once at term-equivalent age. An expert panel blinded to medical information, including imaging findings by the other methods, evaluated the presence of periventricular echogenicity (PVE) changes, peri- and intraventricular hemorrhage (IVH) and changes in basal ganglia and/or thalami echogenicity (BGTE) on ultrasound, and the equivalent signal intensity (SI) changes on MRI. Conclusions on imaging findings were generated by consensus. The children were followed up with examinations for psychomotor development at 1 year of age, using the Touwen examination and Alberta Infant Motor Scale, and at 2 years of age using Bayley Scale of Infant Development-III (BSID-III) and behavioral, sensory profile and linguistic questionnaires; scores > 1 SD below the mean were considered suspicious for neurodevelopmental sequelae. Results: Fifty-six fetuses were examined, and in 39/56 fetuses, all fetal-imaging modalities were available. PVE/SI changes were observed in 6/39, 21/39 and 2/39 fetuses on axial ultrasound planes, multiplanar neurosonography and MRI, respectively. IVH was found in 3/39, 11/39 and 1/39 fetuses, and BGTE/SI changes in 0/39, 12/39 and 0/39 fetuses, respectively. Outcome was suspicious for neurodevelopmental sequelae in 13/46 infants at 1 year, and at 2 years, 41/41 children had scores within 1 SD of the mean on BSID-III and 20 had scores > 1 SD below the mean on the behavioral (5/38), sensory profile (17/37) and/or linguistic (6/39) questionnaires. Conclusions: In this cohort of fetuses at risk for brain damage, the severity of acquired brain anomalies was limited. Nevertheless, multiplanar neurosonography detected more fetal PVE changes, IVH and/or BGTE changes compared to the standard axial ultrasound planes and MRI. Fetal MRI did not demonstrate any anomalies that were not seen on neurosonography. Neurodevelopmental outcome at 2 years of age showed no or mild impairment in most cases.