A morphometric study of the semicircular canals using micro-CT images in three-dimensional reconstruction

Area of Science:

• Anatomy
• Otology
• Biomechanics

Background:

• The semicircular canals' precise spatial relationships are crucial for understanding vestibular function.
• Existing anatomical models often assume right-angle orientations and specific size differences.

Purpose of the Study:

• To accurately measure the dimensions and spatial orientations of the three semicircular canals.
• To create high-resolution 3D models of the bony labyrinth for detailed analysis.

Main Methods:

• Micro-computed tomography (micro-CT) scanning of 40 petrous temporal bones at 35 µm slice thickness.
• 3D reconstruction of the bony labyrinth using specialized computer software.
• Precise measurement of semicircular canal dimensions, radii of curvature, and inter-canal angles.

Main Results:

• The lateral semicircular canal's radius of curvature is 20% smaller than the anterior and posterior canals.
• Inter-canal angles were measured as 92.1° (anterior-posterior), 84.4° (anterior-lateral), and 86.2° (posterior-lateral).
• The anterior semicircular canal was slightly wider than the posterior, with similar heights.

Conclusions:

• The spatial arrangement of semicircular canals deviates from the idealized right-angle model.
• High-resolution 3D reconstruction provides precise data for anatomical and functional studies of the vestibular system.