Three-dimensional cranial suture morphometric changes in young rats during normal growth

Area of Science:

• Craniofacial development
• Biomedical imaging
• Quantitative morphology

Background:

• Age-based morphometric changes in cranial sutures are not well-established quantitatively.
• Previous methods using planar reslicing had limitations in capturing true skull shape and suture length.
• Accurate 3D morphometric analysis of sutures is crucial for understanding normal growth and potential abnormalities.

Purpose of the Study:

• To investigate age-based morphometric changes of the coronal suture in young rats.
• To introduce and validate a novel curved-reslicing approach for 3D suture analysis.
• To establish predictive models for suture morphometric changes during growth.

Main Methods:

• Longitudinal in vivo micro-computed tomography (μCT) scans of 12 Sprague-Dawley rats at five age points (7-21 weeks).
• Application of a novel curved-reslicing technique to generate 3D cross-sectional suture data.
• Measurement of suture linear interdigitation index (LII) and width using a marching algorithm and linear mixed-effect models (LMM).

Main Results:

• Coronal suture LII increased by 15.3% and width decreased by 53.5% from 7 to 21 weeks (p < 0.01).
• Statistically significant age-based differences in LII and width were confirmed.
• LMM explained up to 97% of LII variation and 78% of width variation, considering random effects.

Conclusions:

• A novel curved-reslicing method provides accurate 3D quantitative data for cranial sutures.
• The study successfully demonstrated age-based morphometric changes in rat coronal sutures.
• This methodology offers a powerful tool for future research on craniofacial suture abnormalities.