Early Fetal Corpus Callosum: Demonstrating Normal Growth and Detecting Pathologies in Early Pregnancy

Area of Science:

• Fetal Medicine
• Neuroimaging
• Developmental Biology

Background:

• Malformed corpus callosum is linked to abnormal neurodevelopment.
• High-frequency ultrasound enables early assessment of corpus callosum development.

Purpose of the Study:

• To create a reference chart for fetal corpus callosum length (13-19 weeks gestation).
• To prospectively analyze growth patterns in pathological cases.

Main Methods:

• Prospective cross-sectional study (2020-2022) of 187 low-risk singleton pregnancies.
• Standardized midsagittal plane imaging with specific criteria for corpus callosum confirmation.
• Measurements by 4 sonographers; intra- and interobserver variability assessed.

Main Results:

• Corpus callosum length was measurable in 80% of fetuses at 13 weeks.
• A cubic polynomial regression model showed a strong correlation (r²=0.929) between length and gestational age.
• High intra- and interobserver agreement (>0.99 ICC) was achieved.

Conclusions:

• A nomogram for early fetal corpus callosum length is provided.
• Imaging criteria facilitated early identification of agenesis of the corpus callosum at 14 weeks gestation.