Agenesis of the corpus callosum (ACC) has a wide spectrum of anatomic manifestations associated with incompletely understood clinical variability. In this retrospective cohort study, 161 children with ACC were classified into complete ACC and partial ACC. Partial and complete ACC diagnoses were confirmed by postnatal magnetic resonance imaging (MRI) and further classified as isolated or complex (associated with other brain abnormalities or genetic diagnoses). Clinical characteristics, clinical outcomes, and co-occurring genetic variations were collected by chart review. Median age at last neurologic evaluation for the complete and partial ACC cohorts were 2.8 years and 2.3 years, respectively; thus, an average of 2-3 years of follow-up data were analyzed per patient. Results showed that children with complete and partial ACC had similar birth characteristics. Children with complete ACC were more frequently diagnosed prenatally; additionally, complete ACC patients had lower rates of cerebral palsy. When comparing complex complete ACC and complex partial ACC to isolated complete ACC and isolated partial ACC, respectively, the complex subcohorts had a higher level of motor delay, assistive device use, cerebral palsy, ventriculoperitoneal shunt placement, epilepsy, language delay, and cognitive delay than the isolated subcohorts. About 50% of children had genetic variants associated with neurodevelopmental disorders in this cohort. Additionally, >50% of our patients with motor and nonmotor developmental delays, as well as >60% of patients that required assistive devices and had cerebral palsy, were also found to have genetic anomalies. Although research describing ACC and its outcomes is expanding, there is still a need for large cohort studies with robust follow-up data to help further understand the disease.
Keywords: agenesis of corpus callosum; fetal brain MRI; fetal neurology; neurodevelopment; outcomes.