# Corpus Callosum Size on Magnetic Resonance Imaging and Its Association With Developmental Delays in Children: A Retrospective Case-Control Study

## TL;DR

This study found that children with developmental delays often have a thinner corpus callosum, as seen on MRI scans, suggesting a potential link between brain structure and developmental issues.

## Contribution

The study provides new evidence linking corpus callosum thickness to developmental delays in children using MRI measurements.

## Key findings

- Children with developmental delays had significantly thinner corpus callosum regions compared to typically developing children.
- The most pronounced differences were in the splenium, anterior body, and genu of the corpus callosum.
- Language-delayed children showed significant differences in the genu and splenium thickness.

## Abstract

Introduction

Developmental delay (DD) encompasses a heterogeneous group of conditions that present with a delay in development or an abnormal pattern of developmental progression. The corpus callosum (CC) is the largest white matter structure in the human brain and connects the cerebral hemispheres. The association between DD and CC thickness is poorly documented.

Objectives

The main objective of this study is to compare the thickness of various regions of the CC in children with and without DD, using magnetic resonance imaging (MRI).

Material and methods

This retrospective case-control study included 70 children aged two to six years (35 children each with DD and normal development). The thickness of the CC was measured on mid-sagittal T1-weighted images according to Witelson’s method. Associations between the mean sizes of the different regions of the CC in the case and comparison groups were assessed.

Results

Delayed speech was the most common presentation of DD, followed by delayed fine motor skills. A significant difference (p < 0.005) was observed between the mean thickness of the CC subdivisions in the case and comparison groups. The difference was most pronounced in the regions of the splenium, anterior body, and genu, with effect sizes of 1.59, 1.33, and 1.15, respectively (Cohen’s d values). Significant differences were also observed between the thickness of the genu and splenium in participants who predominantly displayed language delay (p = 0.013).

Conclusion

Corpus callosal thinning is associated with various DDs in the pediatric age group, and the presence of a thin CC on MRI should trigger evaluation for DD.