ORIGINAL ARTICLE Isolated corpus callosum agenesis: a ten-year follow-up after prenatal diagnosis (How are the children without corpus callosum at 10 years of age?) Marie-Laure Moutard 1 , Virginie Kieffer 2,3 , Josué Feingold 1 , Fanny Lewin 4 , Jean-Michel Baron 4 , Catherine Adamsbaum 5 , Antoinette Gélot 6 , Arnaud Isapof 1,7 , François Kieffer 8 and Thierry Billette de Villemeur 1,7,9 1 Service de Neuropédiatrie, Pathologie du développement, Hôpital Trousseau, 26 avenue du Dr Arnold Netter, 75571 Paris, France 2 Centre de Suivi et d’Insertion, Hôpitaux de Saint-Maurice, 14 rue du val d’osne, 94415 Saint-Maurice, France 3 Institut Gustave Roussy, Département de cancérologie de l’enfant et de l’adolescent 114 rue Edouard Vaillant, 94805 Villejuif, France 4 Service gynécologie-obstétrique, Hôpital Cochin – Port Royal, 27 rue du Faubourg saint Jacques, 75679 Paris, France 5 Service de radiologie, Hôpital Bicêtre, 78 rue du Général Leclerc, 94275 Le Kremlin-Bicêtre, France 6 Neuropathologie service d’anatomie pathologique, Hôpital Trousseau, 26 avenue du Dr Arnold Netter, 75571 Paris, France 7 Université Pierre et Marie Curie (Paris 6), Paris, France 8 Neonatal Intensive Care Unit, Institut de Puériculture de Paris, 26 boulevard Brune, 75014 Paris, France 9 Pôle Polyhandicap Pédiatrique, Hôpital de La Roche Guyon, 1 rue de l’Hôpital, 95780 LA ROCHE-GUYON, France *Correspondence to: M.-L. Moutard. E-mail: marielaure.moutard@trs.aphp.fr ABSTRACT Background Corpus callosum agenesis (CCA) is generally diagnosed in utero. Outcome appears to be better if the malformation is isolated. The aim of this study, which is the first one with a long (10 years) and standardized follow up, was to report cognitive abilities of children with isolated CCA diagnosed prenatally. Methods We prospectively evaluated 17 children. Clinical examinations, neuropsychological tests were performed each year. School achievement and personal and familial data were collected. Results Twelve children completed the entire follow up. One child was finally considered to have associated CCA, because signs of fetal alcohol syndrome had become obvious. Of the 11 other children, three (27%) had borderline intelligence whereas the intelligence levels of eight (73%) were in the normal range, although half of these children experienced some difficulties in scholastic achievement. Neither epilepsy nor intellectual deficiency was noted and intellectual quotient scores correlated strongly with the mother’s education level. Conclusion Although prenatal diagnosis of isolated CCA is reliable, false postnatal diagnoses remain possible (10–20%) even with complete prenatal screening. Outcome is mostly favorable because intelligence is within the normal range for nearly 3/4 of the children. However, they frequently have mild learning difficulties. © 2012 John Wiley & Sons, Ltd. Funding sources: None Conflicts of interest: None declared INTRODUCTION Corpus callosum agenesis (CCA) is the most common brain malformation. 1 Beginning in the 1990s, it has been diagnosed prenatally by routine ultrasound at a mean gestational age of 22 weeks. Parental counseling remains a challenge because this malformation can either be completely isolated or be part of many genetic syndromes, aneuploidies, monogenic disorders, metabolic diseases or complex brain anomalies. Thus, CCA correlates with many different phenotypes and prognoses. Several studies have reported prognoses that were poor in associated cases but relatively better if the malformation is isolated. 2,3 Nevertheless, these studies also pointed out that, even with extensive prenatal analysis, it remains difficult to ascertain whether the malformation is isolated. In a previous prospective study, 4 we reported clinical data and a 6-year follow-up of 17 children who were diagnosed prenatally with Prenatal Diagnosis 2012, 32, 277–283 © 2012 John Wiley & Sons, Ltd. DOI: 10.1002/pd.3824