Midbrain and Falx in Fetuses with Absent Corpus Callosum at 11–13 Weeks

• Published in: Fetal diagnosis and therapy Vol. 33; no. 1; pp. 41 - 46
• Main Authors: Lachmann, Robert, Sodre, Danielle, Barmpas, Michail, Akolekar, Ranjit, Nicolaides, Kypros H.
• Format: Journal Article
• Language: English
• Published: Basel, Switzerland Karger 01.01.2013; S. Karger AG
• Subjects: Agenesis of Corpus Callosum - diagnostic imaging; Biological and medical sciences; Case-Control Studies; Delivery. Postpartum. Lactation; Female; General aspects; Gynecology. Andrology. Obstetrics; Humans; Male; Medical sciences; Mesencephalon - diagnostic imaging; Observer Variation; Original Paper; Pregnancy; Pregnancy Trimester, First; Third Ventricle - diagnostic imaging; Ultrasonography, Prenatal; Absent corpus callosum; Nonchromosomal abnormalities; Nuchal translucency; First-trimester screening; Midsagittal view; Neonatology; Midbrain; First trimester; Medical screening; Corpus callosum; Pregnancy; Medicine; Fetus
• ISSN: 1015-3837; 1421-9964
• DOI: 10.1159/000339943

Objective: To describe the first trimester diagnosis of agenesis of the corpus callosum (ACC). Methods: The midbrain and falx cerebri were examined in stored images of the midsagittal view of the fetal brain at 11 +0 –13 +6 weeks’ gestation from 15 fetuses with ACC and 500 normal controls. The midbrain diameter and falx diameter were measured and their ratio was calculated. The values in fetuses with ACC and normal controls were compared. Results: In the control group, the midbrain and falx diameters increased significantly with crown-rump length (CRL) from respective mean values of 5.1 and 6.9 mm at CRL of 45–6.9 mm and 12.1 mm at CRL of 84 mm. In the ACC group the midbrain diameter was above the 95th percentile of the control group in 8 (53.3%) cases, the falx diameter was below the 5th percentile in 6 (40.0%) cases and the midbrain diameter-to-falx diameter ratio was above the 95th percentile in 13 (86.7%) cases. Conclusions: In the midsagittal view of the fetal brain at 11–13 weeks, the majority of fetuses with ACC have measurable abnormalities in the midbrain and falx area of the brain.