Sylvian fissure angle development on fetal MRI: 22-38 gestational weeks

Area of Science:

• Neuroimaging
• Fetal Development
• Quantitative Anatomy

Background:

• The Sylvian fissure (SF) is a key landmark in fetal brain development.
• Accurate quantification of SF development is crucial for assessing neurodevelopmental abnormalities.

Purpose of the Study:

• To quantify Sylvian fissure angle (SFA) development during pregnancy using fetal MRI.
• To establish normative reference ranges and growth curves for SFAs.
• To provide a quantitative framework for detecting deviations indicative of cortical malformations.

Main Methods:

• Retrospective analysis of 324 fetal MRIs (22-38 weeks gestation).
• Measurement of six SFAs (SFPA, SFARA, SFPRA, SFSRA, SFIRA) in axial and coronal planes.
• Correlation analysis with gestational age and growth curve modeling.
• Validation using retrospective cortical malformation cases.

Main Results:

• High interobserver reliability for SFA measurements (ICC 0.772-0.976).
• Significant positive associations between SFARA, SFSRA and gestational age.
• Significant negative associations between SFPRA, SFIRA, SFPA and gestational age.
• Quadratic growth curve models demonstrated the best fit for SFA development.
• The model successfully identified cortical malformations.

Conclusions:

• Fetal MRI effectively evaluates dynamic SFA development.
• Established SFA reference ranges improve fetal brain assessment accuracy.
• Provides a quantitative tool for identifying deviations suggestive of cortical malformations.