A Systematic Review with a Meta-Analysis of the Morphological Variants of the Corpus Callosum: Related Neurocognitive Clinical Implications.

BACKGROUND

Corpus callosum agenesis (CCA) occurs in approximately 1 in every 4000 births and is identified in 3-5% of individuals evaluated through neuroimaging for neurodevelopmental disorders. The combined prevalence of CCA and hypoplasia is estimated to range from 1.8 to 10 in every 10,000 births.

METHODS

The online databases Medline, Scopus, Web of Science, Google Scholar, Cumulative Index to Nursing and Allied Health Literature, and Latin American and Caribbean Literature in Health Sciences were searched until May 2025. Two authors independently conducted the search, selected the studies, and extracted the data. The methodological quality of the studies was assessed using the Anatomical Quality Assessment tool. A random effects model was used to estimate the pooled prevalence.

RESULTS

A total of 46 studies met the established selection criteria. In this analysis, 15 articles were included in the meta-analysis, which involved a total of 5,118,037 subjects. The overall prevalence of CCA was 18% (confidence interval = 10%-25%). The subgroup analysis revealed a significant difference in the prevalence of CCA among the Asian continent compared to the other four continents (P-value 0.001).

CONCLUSIONS

Early diagnosis of CCA during the fetal stage can enable specialists to implement more effective treatments and reduce the likelihood of neurofunctional impairments. Furthermore, understanding the morphological characteristics of CCA can assist in making an early and accurate diagnosis, minimizing the need for differential diagnoses that could interfere with the functioning of the interhemispheric connection system and brain functional connections.