The ultrasound evaluation of corpus callosum in the routine screening is not recommended, because we know less than we see

The corpus callosum serves as a link between the two hemispheres, with an important role in cognitive mechanisms, also integrating motor and sensitive information and processing stimuli. Evaluation of the morphologic structure of the corpus callosum in order to diagnose structural anomalies such as hyperplasia, hypoplasia, as well as indirect signs of corpus callosum agenesia can be realised using ultrasonography during the mid-trimester screening. At present, it is recommended to perform a targeted evaluation only in high-risk cases of central nervous system abnormalities; the International Society of Ultrasound in Obstetrics and Gynaecology has not included the corpus callosum evaluation in the routine second trimester screening. Callosal anomalies present uncertainty in the fetal prognosis: 75% of cases of isolated corpus callosum agenesis develop normally; on the other hand, they could develop various degrees of neurological impairment from language or social deficiency to autism or schizophrenia. We, therefore, highlight the importance of corpus callosum evaluation, as the agenesis of the corpus callosum can be an isolated defect, but it can also be associated with other extracerebral anomalies or it could be a part of a syndrome. Completing the diagnosis often requires magnetic resonance imaging and genetic tests.