Outcome of prenatally diagnosed agenesis of the corpus callosum

Objective To investigate the natural history, associated abnormalities and outcome in fetuses diagnosed prenatally with agenesis of the corpus callosum (ACC). Methods A retrospective study of all cases of prenatally detected ACC was performed in patients referred to two tertiary units between January 1993 and October 2003. Associated abnormalities, pregnancy outcome and infant follow-up were recorded. Results ACC was diagnosed in 117 cases. In 82 (70%) cases this was associated with other fetal structural (n = 49) or chromosomal abnormalities (n = 33). ACC was classified as an isolated prenatal finding in 35 (30%) cases. Assuming normal development in all cases lost to follow-up, significant developmental delay was present in 36% (95% Cl, 15-65%) of isolated ACC. Furthermore, developmental delay was present in all cases with ventriculomegaly of at least 15 mm and in one of four cases with ventricular measurements less than 15 rum. Conclusions The outcome of prenatally detected ACC is mainly dependent on the presence or absence of associated anomalies. The full assessment of fetal ACC mandates karyotyping, MRI and a search for more subtle ultrasound features of certain genetic syndromes. In this series, at least 36% (95% Cl, 15-65%) of cases with isolated ACC exhibited significant developmental delay when assessed postnatally. Copyright (c) 2007 John Wiley & Sons, Ltd.