Analysis of Craniomaxillofacial Malformations in Mice Using Three-dimensional Microcomputed Tomography
January 17th, 2025
Here, we describe in depth a method, which is based on microcomputed tomography, to segment and measure 3D models of craniomaxillofacial bones in mice, for better assessment of craniomaxillofacial bone development in mice than what is possible with current methods.
To begin import Micro-CT image of the mouse skull into the software. Right Click on the Masks page and select New Mask. A new layer named green will appear.
On the Thresholding page that pops up select the required threshold range. Click on the newly created layer green in the Masks page, and select Calculate 3D from the dropdown menu. In the 3D objects interface right click Green and click Properties.
Then click Color to change the coding of all the 3D models reconstructed with different bones. Next, using the eraser tool from the edit menu, manually erase the bones attached to the mandible in each layer on the 2D sagittal plane. After clicking on the region growing option, select the region of the mandible on the 2D sagittal plane.
In the Masks page, select Calculate 3D from the dropdown menu and click on the newly created layer to label it as mandible. Turn off visible right click on the screen and select Zoom to Full Screen. Then click on Measure and select distance from the dropdown menu.
To calculate the length, mark the correct points on the 3D image. In the 3D objects interface, right click on mandible, followed by a Properties and properties info Volume module. To read the reconstructed volume values for each cranio maxillofacial bone block, measure the mandible frontal bone, parietal bone, nasal bone, premaxilla, maxilla, inter parietal bone and occipital bone in the same way.
The Micro-CT analysis showed a dose dependent correlation between dominant negative RAR alpha expression and skeletal defects, including reduced lengths of the mandible, frontal, and parietal bones. The inhibition of our RAR in osteoblasts led to craniofacial deformities characterized by changes in the shape, size, and ossification levels of cranial facial bones.
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Overview
This article details a method utilizing microcomputed tomography to create and analyze 3D models of craniomaxillofacial bones in mice. This approach enhances the assessment of bone development compared to existing techniques.
Key Study Components
Area of Science
- Neuroscience
- Bone Development
- Imaging Techniques
Background
- Craniomaxillofacial bones are crucial for various biological studies.
- Current methods of assessment have limitations.
- Microcomputed tomography offers a novel approach for detailed imaging.
- 3D modeling can improve understanding of bone development.
Purpose of Study
- To develop a method for better segmentation of bone structures.
- To enhance measurement accuracy of craniomaxillofacial bones.
- To provide a reliable tool for researchers studying bone development in mice.
Methods Used
- Importing Micro-CT images into specialized software.
- Creating new masks for segmentation.
- Applying thresholding techniques for accurate modeling.
- Calculating 3D representations of the segmented bones.
Main Results
- Successful segmentation of craniomaxillofacial bones.
- Improved accuracy in 3D modeling compared to traditional methods.
- Enhanced visualization of bone structures.
- Potential for broader applications in biological research.
Conclusions
- The method significantly improves the assessment of bone development.
- Microcomputed tomography is a valuable tool in neuroscience research.
- Future studies can leverage this technique for various applications.
Frequently Asked Questions
Executive Industry Relevance
Quantitative 3D microCT analysis of murine craniomaxillofacial bones enables precise assessment of genetic and developmental perturbations relevant to skeletal disease modeling. This workflow enhances predictive confidence in early-stage target validation and supports mechanistic de-risking for bone and craniofacial therapeutic discovery. Accurate segmentation and measurement of individual bones facilitate robust phenotypic screening and translational continuity across preclinical models.
Strategic Applications in Biopharma R&D
Early Discovery & Target Validation
- Enables quantitative interrogation of gene function and pathway impact on craniofacial bone development.
- Supports mechanistic de-risking by linking genetic mutations to discrete skeletal phenotypes.
- Facilitates functional target validation through reproducible morphometric outputs.
Screening & Assay Development
- Provides standardized, reproducible segmentation and measurement of multiple craniofacial bones.
- Delivers quantitative outputs suitable for high-confidence phenotypic screening.
- Prepares validated biological systems for downstream compound evaluation and comparative studies.
Translational & Preclinical Research
- Aligns preclinical bone phenotypes with disease-relevant endpoints for translational biomarker development.
- Enables continuity from genetic discovery through preclinical validation in skeletal disease models.
- Supports risk-adjusted advancement decisions based on robust morphometric data.
Pipeline & Workflow Integration
This microCT-based segmentation and quantification method integrates from early discovery through preclinical model validation in skeletal and craniofacial research.
- Discovery Biology: Supports hypothesis testing and pathway clarification by quantifying bone-specific effects of genetic perturbations.
- Screening: Delivers reproducible, quantitative morphometric outputs for assay standardization and screening readiness.
- Analytics: Provides volumetric and dimensional measurements enabling statistical comparison across experimental groups.
- Translational Research: Facilitates alignment of preclinical bone phenotypes with clinical endpoints in craniofacial disorders.
- Enterprise Reuse: Establishes a scalable, reusable imaging and analysis capability for diverse skeletal disease models.
Operational & Enterprise Impact
- Scientific Value: Increases predictive confidence and reduces mechanistic ambiguity in skeletal target validation.
- Operational Value: Standardizes image segmentation and measurement for reproducibility and scalability.
- Strategic Value: Improves go/no-go decisions and capital efficiency by providing robust quantitative endpoints.
- Portfolio Impact: Enables risk-adjusted prioritization and advancement of skeletal and craniofacial programs.
Implementation Considerations
- Requires expertise in microCT imaging and segmentation software.
- Demands access to high-resolution microCT instrumentation and analytical infrastructure.
- Benefits from cross-team standardization of segmentation protocols and measurement criteria.
- Adaptable to various genetic and disease models with appropriate parameter adjustments.
- Manual segmentation steps may limit throughput for large-scale studies.
